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Khan I, Hussain M, Jiang B, Zheng L, Pan Y, Hu J, Khan A, Ashraf A, Zou X. Omega-3 long-chain polyunsaturated fatty acids: Metabolism and health implications. Prog Lipid Res 2023; 92:101255. [PMID: 37838255 DOI: 10.1016/j.plipres.2023.101255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 10/04/2023] [Accepted: 10/09/2023] [Indexed: 10/16/2023]
Abstract
Recently, omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs) have gained substantial interest due to their specific structure and biological functions. Humans cannot naturally produce these fatty acids (FAs), making it crucial to obtain them from our diet. This comprehensive review details n-3 LC-PUFAs and their role in promoting and maintaining optimal health. The article thoroughly analyses several sources of n-3 LC-PUFAs and their respective bioavailability, covering marine, microbial and plant-based sources. Furthermore, we provide an in-depth analysis of the biological impacts of n-3 LC-PUFAs on health conditions, with particular emphasis on cardiovascular disease (CVD), gastrointestinal (GI) cancer, diabetes, depression, arthritis, and cognition. In addition, we highlight the significance of fortification and supplementation of n-3 LC-PUFAs in both functional foods and dietary supplements. Additionally, we conducted a detailed analysis of the several kinds of n-3 LC-PUFAs supplements currently available in the market, including an assessment of their recommended intake, safety, and effectiveness. The dietary guidelines associated with n-3 LC-PUFAs are also highlighted, focusing on the significance of maintaining a well-balanced intake of n-3 PUFAs to enhance health benefits. Lastly, we highlight future directions for further research in this area and their potential implications for public health.
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Affiliation(s)
- Imad Khan
- State Key Laboratory of Food Science and Resources, National Engineering Research Center for Functional Food, National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, China
| | - Mudassar Hussain
- State Key Laboratory of Food Science and Resources, National Engineering Research Center for Functional Food, National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, China
| | - Bangzhi Jiang
- State Key Laboratory of Food Science and Resources, National Engineering Research Center for Functional Food, National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, China
| | - Lei Zheng
- State Key Laboratory of Food Science and Resources, National Engineering Research Center for Functional Food, National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, China
| | - Yuechao Pan
- State Key Laboratory of Food Science and Resources, National Engineering Research Center for Functional Food, National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, China
| | - Jijie Hu
- State Key Laboratory of Food Science and Resources, National Engineering Research Center for Functional Food, National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, China
| | - Adil Khan
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Azqa Ashraf
- School of Food Science and Engineering, Ocean University of China, Qingdao 2666100, China
| | - Xiaoqiang Zou
- State Key Laboratory of Food Science and Resources, National Engineering Research Center for Functional Food, National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, China.
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Decsi T, Marosvölgyi T, Szabó É. Docosahexaenoic Acid in Formulas for Term Infants: The Way from Pioneer Idea to Mandatory Dietary Recommendation. Life (Basel) 2023; 13:1326. [PMID: 37374109 DOI: 10.3390/life13061326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 05/23/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
Docosahexaenoic acid (DHA) is a novel mandatory constituent of breast-milk-substitute infant formula in Europe. The aim of the present narrative review was to summarize available data in connection with the background of the novel European mandatory dietary recommendation to add at least 20 mg/100 kcal (4.8 mg/100 kJ) DHA to infant formula. The literature search with the expression "docosahexaenoic acid with (infant or human milk or formula)" revealed nearly 2000 papers, including more than 400 randomized controlled trials (RCTs). DHA is a persistent constituent of human milk (HM) with a worldwide mean level of 0.37% (standard deviation: 0.11%) of all fatty acids in HM. RCTs on supplementing DHA to lactating women showed some indications, though no direct evidence of the beneficial effect of enhanced HM DHA on the development of breastfed infants. The most-recent Cochrane review of RCTs investigating the effect of DHA supplementation to infant formula for full-term infants reported no evidence for recommending supplementation. The controversy between the Cochrane view and the actual recommendation may be related to the numerous hurdles in organizing high-quality studies in this field. On the basis of the official food composition recommendation, today in Europe, DHA should be considered as a fatty acid essential for infants.
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Affiliation(s)
- Tamás Decsi
- Department of Pediatrics, Medical School and Clinical Centre, University of Pécs, 7623 Pécs, Hungary
- Cochrane Hungary, Clinical Centre, University of Pécs, 7623 Pécs, Hungary
| | - Tamás Marosvölgyi
- Institute of Bioanalysis, Medical School, University of Pécs, 7624 Pécs, Hungary
| | - Éva Szabó
- Department of Biochemistry and Medical Chemistry, Medical School, University of Pécs, 7624 Pécs, Hungary
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Einerhand AWC, Mi W, Haandrikman A, Sheng XY, Calder PC. The Impact of Linoleic Acid on Infant Health in the Absence or Presence of DHA in Infant Formulas. Nutrients 2023; 15:2187. [PMID: 37432333 DOI: 10.3390/nu15092187] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/27/2023] [Accepted: 05/01/2023] [Indexed: 07/12/2023] Open
Abstract
Both linoleic acid (LA) and α-linolenic acid (ALA) are essential dietary fatty acids, and a balanced dietary supply of these is of the utmost importance for health. In many countries across the globe, the LA level and LA/ALA ratio in breast milk (BM) are high. For infant formula (IF), the maximum LA level set by authorities (e.g., Codex or China) is 1400 mg LA/100 kcal ≈ 28% of total fatty acid (FA) ≈ 12.6% of energy. The aims of this study are: (1) to provide an overview of polyunsaturated fatty acid (PUFA) levels in BM across the world, and (2) to determine the health impact of different LA levels and LA/ALA ratios in IF by reviewing the published literature in the context of the current regulatory framework. The lipid composition of BM from mothers living in 31 different countries was determined based on a literature review. This review also includes data from infant studies (intervention/cohort) on nutritional needs regarding LA and ALA, safety, and biological effects. The impact of various LA/ALA ratios in IF on DHA status was assessed within the context of the current worldwide regulatory framework including China and the EU. Country averages of LA and ALA in BM range from 8.5-26.9% FA and 0.3-2.65% FA, respectively. The average BM LA level across the world, including mainland China, is below the maximum 28% FA, and no toxicological or long-term safety data are available on LA levels > 28% FA. Although recommended IF LA/ALA ratios range from 5:1 to 15:1, ratios closer to 5:1 seem to promote a higher endogenous synthesis of DHA. However, even those infants fed IF with more optimal LA/ALA ratios do not reach the DHA levels observed in breastfed infants, and the levels of DHA present are not sufficient to have positive effects on vision. Current evidence suggests that there is no benefit to going beyond the maximum LA level of 28% FA in IF. To achieve the DHA levels found in BM, the addition of DHA to IF is necessary, which is in line with regulations in China and the EU. Virtually all intervention studies investigating LA levels and safety were conducted in Western countries in the absence of added DHA. Therefore, well-designed intervention trials in infants across the globe are required to obtain clarity about optimal and safe levels of LA and LA/ALA ratios in IF.
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Affiliation(s)
| | - Wiola Mi
- Bunge Loders Croklaan Nutrition, Shanghai 200051, China
| | | | - Xiao-Yang Sheng
- Department of Developmental Behavioral Pediatric & Children Healthcare, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200051, China
| | - Philip C Calder
- School of Human Development and Health, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust and University of Southampton, Southampton SO16 6YD, UK
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Choi HN, Choue R, Park Y, Yim JE. Onion Peel Extract Increases Erythrocyte Membrane n-3 Fatty Acids in Overweight and Obese Korean Subjects. J Med Food 2019; 23:37-42. [PMID: 31855493 DOI: 10.1089/jmf.2018.4366] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The association between obesity and erythrocyte fatty acids (FAs) has been suggested; however, there have been no studies on the effects of onion peel extract (OPE) on the composition of erythrocyte FAs. This study aimed to investigate the effects of OPE on the composition of erythrocyte FAs in overweight and obese subjects. This was a randomized, double-blind, and placebo-controlled trial conducted in overweight and obese Korean subjects. The placebo and OPE groups were taking placebo capsule or OPE capsule twice per day for 12 weeks. Body composition and fat distribution were measured using dual-energy X-ray absorptiometry. The OPE group showed significantly reduced body weight, body mass index, body fat mass, and percentage of body fat mass. After 12 weeks, eicosapentaenoic acid and monounsaturated FAs of the placebo group were significantly lower at baseline. Consumption of OPE ameliorated the decreasing polyunsaturated n-3 polyunsaturated FA (PUFA) n-3 and increasing PUFA n-6, which prevented an increased n-6/n-3 ratio. The changes in arm fat percentage (ARFATP), trunk fat percentage, and total fat percentage (FATP) were negatively correlated with the change in PUFA n-3. In addition, increased erythrocyte docosahexaenoic acid was associated with decreased ARFATP and FATP. These results suggest that OPE has beneficial effects on obesity by regulating erythrocyte n-6/n-3 ratio and preventing fat accumulation in various body regions.
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Affiliation(s)
- Ha-Neul Choi
- Department of Food and Nutrition, Changwon National University, Changwon, Korea
| | - Ryowon Choue
- Department of Medical Nutrition, Graduate School of East-West Medical Science, Kyung Hee University, Yongin, Korea
| | - Yongsoon Park
- Department of Food and Nutrition, Hanyang University, Seoul, Korea
| | - Jung-Eun Yim
- Department of Food and Nutrition, Changwon National University, Changwon, Korea
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Johnson M, Pace RD, McElhenney WH. Green leafy vegetables in diets with a 25:1 omega-6/omega-3 fatty acid ratio modify the erythrocyte fatty acid profile of spontaneously hypertensive rats. Lipids Health Dis 2018; 17:140. [PMID: 29907155 PMCID: PMC6003211 DOI: 10.1186/s12944-018-0723-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 03/25/2018] [Indexed: 02/06/2023] Open
Abstract
Background In addition to the actual composition of the diet (i.e. nutrient composition, food groups), the omega-6/omega-3 fatty acid ratio has been demonstrated to influence the tissue fatty acid profile and subsequently the risk for cardiovascular and other diseases. Likewise, the consumption of green leafy vegetables (GLVs) may favorably reduce the risks associated with disease. Although an ~ 3:1 omega-6/omega-3 fatty acid ratio (ω-6/ω-3 FAR) is recommended, the typical American diet has an ~ 25:1 ω-6/ω-3 FAR. Previous research affirms the ability of collard greens (CG), purslane (PL), and sweet potato greens (SPG) to improve the hepatic profile of spontaneously hypertensive rats (SHRs). The aim of the present study was to determine the influence of GLVs, incorporated (4%) into diets with a 25:1 ω-6/ω-3 FAR, on the erythrocyte fatty acid profile of male SHRs. Methods SHRs (N = 50) were randomly assigned to one of five dietary groups – standardized control (AIN-76A), Control (25:1 ω-6/ω-3 FAR), CG (25:1 ω-6/ω-3 FAR + 4% CG), PL (25:1 ω-6/ω-3 FAR + 4% PL) or SPG (25:1 ω-6/ω-3 FAR + 4% SPG). Following 6 weeks consumption of diets, SHRs erythrocyte fatty acid profiles were determined by gas-liquid chromatography. Results Significantly lower percentages of total saturated fatty acids (p < 0.05) and greater percentages of polyunsaturated fatty acids were present among SHR erythrocytes following the consumption of diets containing CG, PL and SPG. Total polyunsaturated fatty acids were greatest among SHRs consuming diets containing purslane. Conclusions The present study demonstrates the ability of GLVs to mitigate the potential effects of an elevated ω-6/ω-3 FAR, which may contribute to an atherogenic fatty acid profile, inflammation and disease pathogenesis. Dietary recommendations for disease prevention should consider the inclusion of these GLVs, particularly among those consuming diets with an ω-6/ω-3 FAR that may promote disease.
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Affiliation(s)
- Melissa Johnson
- Department of Food and Nutritional Sciences, Tuskegee University, Tuskegee, AL, 36088, USA.
| | - Ralphenia D Pace
- Department of Food and Nutritional Sciences, Tuskegee University, Tuskegee, AL, 36088, USA
| | - Wendell H McElhenney
- Department of Agricultural and Environmental Sciences, Tuskegee University, Tuskegee, AL, 36088, USA
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Westmark CJ. Soy-Based Therapeutic Baby Formulas: Testable Hypotheses Regarding the Pros and Cons. Front Nutr 2017; 3:59. [PMID: 28149839 PMCID: PMC5241282 DOI: 10.3389/fnut.2016.00059] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 12/23/2016] [Indexed: 12/18/2022] Open
Abstract
Soy-based infant formulas have been consumed in the United States since 1909, and currently constitute a significant portion of the infant formula market. There are efforts underway to generate genetically modified soybeans that produce therapeutic agents of interest with the intent to deliver those agents in a soy-based infant formula platform. The threefold purpose of this review article is to first discuss the pros and cons of soy-based infant formulas, then present testable hypotheses to discern the suitability of a soy platform for drug delivery in babies, and finally start a discussion to inform public policy on this important area of infant nutrition.
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Affiliation(s)
- Cara J Westmark
- Department of Neurology, University of Wisconsin , Madison, WI , USA
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Schindler T, Sinn JKH, Osborn DA. Polyunsaturated fatty acid supplementation in infancy for the prevention of allergy. Cochrane Database Syst Rev 2016; 10:CD010112. [PMID: 27788565 PMCID: PMC6464137 DOI: 10.1002/14651858.cd010112.pub2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Early dietary intakes may influence the development of allergic disease. It is important to determine if dietary polyunsaturated fatty acids (PUFAs) given as supplements or added to infant formula prevent the development of allergy. OBJECTIVES To determine the effect of higher PUFA intake during infancy to prevent allergic disease. SEARCH METHODS We used the standard search strategy of the Cochrane Neonatal Review group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 9), MEDLINE (1966 to 14 September 2015), EMBASE (1980 to 14 September 2015) and CINAHL (1982 to 14 September 2015). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. SELECTION CRITERIA Randomised and quasi-randomised controlled trials that compared the use of a PUFA with no PUFA in infants for the prevention of allergy. DATA COLLECTION AND ANALYSIS Two review authors independently selected trials, assessed trial quality and extracted data from the included studies. We used fixed-effect analyses. The treatment effects were expressed as risk ratio (RR) with 95% confidence intervals (CI). We used the GRADE approach to assess the quality of evidence. MAIN RESULTS The search found 17 studies that assessed the effect of higher versus lower intake of PUFAs on allergic outcomes in infants. Only nine studies enrolling 2704 infants reported allergy outcomes that could be used in meta-analyses. Of these, there were methodological concerns for eight.In infants up to two years of age, meta-analyses found no difference in incidence of all allergy (1 study, 323 infants; RR 0.96, 95% CI 0.73 to 1.26; risk difference (RD) -0.02, 95% CI -0.12 to 0.09; heterogeneity not applicable), asthma (3 studies, 1162 infants; RR 1.04, 95% CI 0.80 to 1.35, I2 = 0%; RD 0.01, 95% CI -0.04 to 0.05, I2 = 0%), dermatitis/eczema (7 studies, 1906 infants; RR 0.93, 95% CI 0.82 to 1.06, I2 = 0%; RD -0.02, 95% CI -0.06 to 0.02, I2 = 0%) or food allergy (3 studies, 915 infants; RR 0.81, 95% CI 0.56 to 1.19, I2 = 63%; RD -0.02, 95% CI -0.06 to 0.02, I2 = 74%). There was a reduction in allergic rhinitis (2 studies, 594 infants; RR 0.47, 95% CI 0.23 to 0.96, I2 = 6%; RD -0.04, 95% CI -0.08 to -0.00, I2 = 54%; number needed to treat for an additional beneficial outcome (NNTB) 25, 95% CI 13 to ∞).In children aged two to five years, meta-analysis found no difference in incidence of all allergic disease (2 studies, 154 infants; RR 0.69, 95% CI 0.47 to 1.02, I2 = 43%; RD -0.16, 95% CI -0.31 to -0.00, I2 = 63%; NNTB 6, 95% CI 3 to ∞), asthma (1 study, 89 infants; RR 0.45, 95% CI 0.20 to 1.02; RD -0.20, 95% CI -0.37 to -0.02; heterogeneity not applicable; NNTB 5, 95% CI 3 to 50), dermatitis/eczema (2 studies, 154 infants; RR 0.65, 95% CI 0.34 to 1.24, I2 = 0%; RD -0.09 95% CI -0.22 to 0.04, I2 = 24%) or food allergy (1 study, 65 infants; RR 2.27, 95% CI 0.25 to 20.68; RD 0.05, 95% CI -0.07 to 0.16; heterogeneity not applicable).In children aged two to five years, meta-analysis found no difference in prevalence of all allergic disease (2 studies, 633 infants; RR 0.98, 95% CI 0.81 to 1.19, I2 = 36%; RD -0.01, 95% CI -0.08 to 0.07, I2 = 0%), asthma (2 studies, 635 infants; RR 1.12, 95% CI 0.82 to 1.53, I2 = 0%; RD 0.02, 95% CI -0.04 to 0.09, I2 = 0%), dermatitis/eczema (2 studies, 635 infants; RR 0.81, 95% CI 0.59 to 1.09, I2 = 0%; RD -0.04 95% CI -0.11 to 0.02, I2 = 0%), allergic rhinitis (2 studies, 635 infants; RR 1.02, 95% CI 0.83 to 1.25, I2 = 0%; RD 0.01, 95% CI -0.06 to 0.08, I2 = 0%) or food allergy (1 study, 119 infants; RR 0.27, 95% CI 0.06 to 1.19; RD -0.10, 95% CI -0.20 to -0.00; heterogeneity not applicable; NNTB 10, 95% CI 5 to ∞). AUTHORS' CONCLUSIONS There is no evidence that PUFA supplementation in infancy has an effect on infant or childhood allergy, asthma, dermatitis/eczema or food allergy. However, the quality of evidence was very low. There was insufficient evidence to determine an effect on allergic rhinitis.
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Affiliation(s)
- Tim Schindler
- Royal Hospital for WomenDepartment of Newborn CareBarker StreetRandwickNSWAustralia2031
| | - John KH Sinn
- Royal North Shore Hospital, The University of SydneyDepartment of NeonatologySt. Leonard'sSydneyNew South WalesAustralia2065
| | - David A Osborn
- University of SydneyCentral Clinical School, Discipline of Obstetrics, Gynaecology and NeonatologySydneyNSWAustralia2050
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Fatty acid supply with complementary foods and LC-PUFA status in healthy infants: results of a randomised controlled trial. Eur J Nutr 2015; 55:1633-44. [DOI: 10.1007/s00394-015-0982-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 06/29/2015] [Indexed: 12/20/2022]
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Heinig MJ, Dewey KG. Health advantages of breast feeding for infants: a critical review. Nutr Res Rev 2013; 9:89-110. [PMID: 19094266 DOI: 10.1079/nrr19960007] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- M J Heinig
- Department of Nutrition, University of California, Davis, CA 95616, USA
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Robson AA. Preventing diet induced disease: bioavailable nutrient-rich, low-energy-dense diets. Nutr Health 2009; 20:135-66. [PMID: 19835109 DOI: 10.1177/026010600902000205] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
What the World needs is an integrated and sustainable food policy that makes the best and most appropriate use of the technologies at our disposal to promote health and help prevent disease. Diet induced diseases account for the largest burden of chronic illnesses and health problems Worldwide. Historically a lack of knowledge about human nutritional requirements (including for the brain) helped promote diet induced disease. The scientific knowledge currently exists to help prevent many of the current deficiencies and imbalances in human diet. Primary prevention of cardiovascular disease and mental ill health starts, crucially, with maternal nutrition before the inception of pregnancy and continues throughout life of the new born and includes consuming more DHA and EPA omega-3 fats (and their cofactors) and other bioavailable brain nutrients and less high-energy-dense (>2 kcal g(-1)) foods (e.g. land-based cereal, chocolate, alcohol and refined sugar, fat and oil), so tissues synthesize less inflammatory mediators and to lower transient short-lived meal-induced oxidative stress, inflammation, proliferation and impaired nitric oxide (e.g. approximately 0.35-3.5 g DHA/ EPA day(-1) dependant on energy intake and noting the importance of cofactors). Micro- and nanotechnologies are already engineering nano foods for human (and livestock) consumption that may eventually (without excessive consumption) prevent the current diet induced disease epidemic, especially in future generations, by preventing the causal mechanisms of disease. Greater knowledge about the causal mechanisms of disease awaits to be discovered, which could further enhance the human desire to increase longevity in optimum health (creating more problems and challenges for society).
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Affiliation(s)
- Anthony A Robson
- Université de Bretagne Occidentale, IUEM (UMR CNRS 6539), LEMAR, Technopôle Brest-Iroise, Plouzané, France.
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Angela Liou Y, Innis SM. Dietary linoleic acid has no effect on arachidonic acid, but increases n-6 eicosadienoic acid, and lowers dihomo-gamma-linolenic and eicosapentaenoic acid in plasma of adult men. Prostaglandins Leukot Essent Fatty Acids 2009; 80:201-6. [PMID: 19356914 DOI: 10.1016/j.plefa.2009.02.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Accepted: 02/18/2009] [Indexed: 11/20/2022]
Abstract
High intakes of linoleic acid (LA,18:2n-6) have raised concern due to possible increase in arachidonic acid (ARA, 20:4n-6) synthesis, and inhibition of alpha linolenic acid (ALA, 18:3n-3) desaturation to eicosapentaenoic (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). In healthy men, 10.5% energy compared to 3.8% energy LA with 1% energy ALA increased plasma phospholipid LA and 20:2n-6, the elongation product of LA, and decreased EPA, with no change in ARA. However, LA was inversely related to ARA at both 10.5% energy and 3.8% energy LA, (r=-0.761, r=-0.817, p<0.001, respectively). A two-fold variability in ARA among individuals was not explained by the dietary LA, ARA, ALA, or fish intake. Our results confirm LA requirements for ARA synthesis is low, <3.8% energy, and they suggest current LA intakes saturate Delta-6 desaturation and adversely affect n-3 fatty acid metabolism. Factors other than n-6 fatty acid intake are important modifiers of plasma ARA.
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Affiliation(s)
- Y Angela Liou
- Nutrition Research Program, Child and Family Research Institute, Department of Paediatrics, University of British Columbia, 950 West 28th Avenue, Vancouver, B.C., V5Z 4H4, Canada
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Omega-3 Fatty acids and neural development to 2 years of age: do we know enough for dietary recommendations? J Pediatr Gastroenterol Nutr 2009; 48 Suppl 1:S16-24. [PMID: 19214053 DOI: 10.1097/mpg.0b013e31819773cf] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
The omega (omega)-3 fatty acids are essential nutrients, explained by the absence of a Delta-15 desaturase in mammalian cells. The omega-3 fatty acids are found in the diet as alpha-linolenic acid (18:3omega-3) and eicosapentaenoic acid (20:5omega-3), as well as docosahexaenoic acid (DHA), with different functions of each of the omega-3 fatty acids in different cells. One essential role of the omega-3 fatty acids is fulfilled by the 22 carbon DHA (22:6omega-3). Depletion of DHA from brain and retina interferes with normal neurogenesis and neurological function, and visual signaling pathways. Observation and intervention studies with pregnant and lactating women, and with infants fed some formulas show that dietary DHA is associated with higher scores on tests of visual and neural development in infants and children. The estimated average requirement and variability in requirement among individuals both of which are needed to set dietary recommended intakes (DRIs) for the different omega-3 fatty acids are unknown. However, because omega-3 fatty acids are essential, adequate intakes to minimize risk of poor neural development and function can be justified, but dose-response data to provide a safe upper limit with different omega-6 fatty acid intakes are needed. Dietary recommendations do affect the food supply and supplements and are used in labeling, all impacting population health. When scientific information is incomplete, consideration must be given to the implications of recommendations that focus on individual nutrients, rather than dietary patterns such as breast-feeding and consuming fish that promote health and minimize disease risk.
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Innis SM. Dietary omega 3 fatty acids and the developing brain. Brain Res 2008; 1237:35-43. [PMID: 18789910 DOI: 10.1016/j.brainres.2008.08.078] [Citation(s) in RCA: 383] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Revised: 08/21/2008] [Accepted: 08/22/2008] [Indexed: 01/04/2023]
Abstract
The omega-3 fatty acids are essential dietary nutrients and one of their important roles is providing the fatty acid with 22 carbons and 6 double bonds known as docosahexaenoic acid (DHA) for nervous tissue growth and function. Inadequate intakes of omega-3 fatty acids decrease DHA and increase omega-6 fatty acids in the brain. Decreased DHA in the developing brain leads to deficits in neurogenesis, neurotransmitter metabolism, and altered learning and visual function in animals. Western diets are low in omega-3 fatty acids, including the 18 carbon omega-3 fatty acid alpha linolenic acid found mainly in plant oils, and DHA, which is found mainly in fish. The DHA status of the newborn and breast-fed infant depends on the maternal intake of DHA and varies widely. Epidemiological studies have linked low maternal DHA to increased risk of poor child neural development. Intervention studies have shown improving maternal DHA nutrition decreases the risk of poor infant and child visual and neural development. Thus, sufficient evidence is available to conclude that maternal fatty acid nutrition is important to DHA transfer to the infant before and after birth, with short and long-term implications for neural function. However, genetic variation in genes encoding fatty acid desaturases also influence essential fatty acid metabolism, and may increase requirements in some individuals. Consideration of omega-3 fatty acid to include brain development, optimizing omega-3 and omega-6 fatty acids in gestation and lactation, and in fatty acid nutrition support for intravenous and formula-fed neonates is important.
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Affiliation(s)
- Sheila M Innis
- Nutrition Research Program, Child and Family Research Institute, Department of Paediatrics, University of British Columbia, 950 West 28th Avenue, Vancouver, B.C., Canada.
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Novak EM, Dyer RA, Innis SM. High dietary omega-6 fatty acids contribute to reduced docosahexaenoic acid in the developing brain and inhibit secondary neurite growth. Brain Res 2008; 1237:136-45. [PMID: 18710653 DOI: 10.1016/j.brainres.2008.07.107] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 07/24/2008] [Accepted: 07/26/2008] [Indexed: 11/30/2022]
Abstract
Docosahexaenoic acid (DHA, 22:6omega-3) is a major polyunsaturated fatty acid in the brain and is required in large amounts during development. Low levels of DHA in the brain are associated with functional deficits. The omega-3 fatty acids are essential nutrients and their metabolism and incorporation in developing brain depends on the composition of dietary fat. We assessed the importance of the intake of the omega-3 fatty acid, 18:3omega-3 and the balance with the omega-6 fatty acid, 18:2omega-6, and the effects of dietary arachidonic acid (20:4omega-6) and DHA in milk diets using the piglet as a model of early infant nutrition. Piglets were fed (% energy) 1.2% 18:2omega-6 and 0.05% 18:3omega-3 (deficient), 10.7% 18:2omega-6 and 1.1% 18:3omega-3 (contemporary), 1.2% 18:2omega-6 and 1.1% 18:3omega-3 (evolutionary), or the contemporary diet with 0.3% 20:4omega-6 and 0.3% DHA (supplemented) from birth to 30 days of age. Our results show that a contemporary diet, high in 18:2omega-6 compromises DHA accretion and leads to increased 22:4omega-6 and 22:5omega-6 in the brain. However, an evolutionary diet, low in 18:2omega-6, supports high brain DHA. DHA supplementation effectively increased DHA, but not the intermediate omega-3 fatty acids, 20:5omega-3 and 22:5omega-3. Using primary cultures of cortical neurons, we show that 22:5omega-6 is efficiently acylated and preferentially taken up over DHA. However, DHA, but not 22:5omega-6 supports growth of secondary neurites. Our results suggest the need to consider whether current high dietary omega-6 fatty acid intakes compromise brain DHA accretion and contribute to poor neurodevelopment.
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Affiliation(s)
- Elizabeth M Novak
- Nutrition Research Program, Child and Family Research Institute, Department of Paediatrics, University of British Columbia, Vancouver, B.C., Canada
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15
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Abstract
Fatty acids play central roles in growth and development through their roles in membrane lipids, as ligands for receptors and transcription factors that regulate gene expression, precursor for eicosanoids, in cellular communication, and through direct interactions with proteins. Adverse fatty acid supplies during fetal and child development alter the fatty acid composition of membrane phospholipids and storage triglycerides with the potential to disrupt cellular environments, and program structure and function. Maternal fatty acid nutrition during pregnancy and lactation determines the transfer of essential n-6 and n-3, and non-essential trans fatty acids via the placenta and through human milk. Poor maternal docosahexaenoic acid (DHA) status increases risk of inadequate DHA to support brain and retinal development, delaying or limiting neural and visual system development. The implications of recent changes in the dietary fatty acids on maternal to infant fatty acid transfer, including the composition of human milk has been insufficiently studied.
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Abstract
Human milk provides all the dietary essential fatty acids, linoleic acid (LA; 18:2n-6) and alpha-linolenic acid (18:3n-3), as well as their longer-chain more-unsaturated metabolites, including arachidonic acid (20:4n-6) and DHA (22:6n-3) to support the growth and development of the breast-fed infant. Human milk levels of LA have increased in Westernized nations from mean levels (g/100 g total fatty acids) of 6 to 12-16 over the last century, paralleling the increase in dietary intake of LA-rich vegetable oils. DHA levels (g/100 g total milk fatty acids) vary from 1% and are lowest in countries in which the intake of DHA from fish and other animal tissue lipids is low. The role of DHA in infant nutrition is of particular importance because DHA is accumulated specifically in the membrane lipids of the brain and retina, where it is important to visual and neural function. An important question is the extent to which many human diets that contain low amounts of n-3 fatty acids may compromise human development. The present paper reviews current knowledge on maternal diet and human milk fatty acids, the implications of maternal diet as the only source of essential fatty acids for infant development both before and after birth, and recent studies addressing the maternal intakes and milk DHA levels associated with risk of low infant neural system maturation.
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Affiliation(s)
- Sheila M Innis
- Nutrition Research Program, Child and Family Research Institute, University of British Columbia, 950 West 28th Avenue, Vancouver, BC V5Z 4H4, Canada.
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17
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Position of the American Dietetic Association and Dietitians of Canada: Dietary Fatty Acids. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.jada.2007.07.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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18
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Savion I, Savion I. Nursing of malnourished children with emphasis on polyunsaturated fatty acids. Appl Nurs Res 2007; 20:140-5. [PMID: 17693217 DOI: 10.1016/j.apnr.2006.05.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2005] [Revised: 05/01/2006] [Accepted: 05/05/2006] [Indexed: 11/16/2022]
Abstract
Omega-3 (Omega-3) and omega-6 (Omega-6) fatty acids (FAs) are essential FAs needed for brain and retina development and maintenance of red blood cell (RBC) membranes. This study investigated the association between the profile of FAs in the membranes of RBCs and malnutrition in children. Demographic, anthropometric, and breast-feeding data and blood samples for analysis of FAs were obtained from malnourished and well-nourished children. The results indicate significant between-group differences in the profile of FAs. These findings support the need for adequate intake of Omega-3 FAs in promoting optimal growth and development processes and emphasize the role of nurses as providers of nutritional and anticipatory guidance for parents and caretakers.
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Affiliation(s)
- Inbal Savion
- Nursing School of Hadassah and the Hebrew University, Israel.
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19
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Abstract
The (n-3) fatty acids are essential dietary nutrients, and one of their important roles is providing docosahexaenoic acid [22:6(n-3)] (DHA) for growth and function of nervous tissue. Reduced DHA is associated with impairments in cognitive and behavioral performance, effects which are particularly important during brain development. Recent studies suggest that DHA functions in neurogenesis, neurotransmission, and protection against oxidative stress. These functions relate to the roles of DHA within the hydrophobic core of neural membranes and effects of unesterified DHA. Reviewed here are some of the recent studies that have begun to elucidate the role of DHA in brain development and function. A better understanding of development and age-specific changes in DHA transfer and function in the developing brain may provide important insight into the role of DHA in developmental disorders in infants and children, as well as at other stages of the lifespan.
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Affiliation(s)
- Sheila M Innis
- Nutrition Research Program, Child and Family Research Institute, University of British Columbia, Vancouver, BC V5Z 4H4, Canada.
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20
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Fatty acid composition of white adipose tissue and breast milk of Mauritian and French mothers and erythrocyte phospholipids of their full-term breast-fed infants. Br J Nutr 2007. [DOI: 10.1017/s0007114599001464] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The fatty acid compositions of white adipose tissue, colostrum and mature milk triacylglycerols from Mauritian (n 13) and French (n 15) women were analysed and compared in order to highlight cultural differences in dietary intakes and their influence on milk fatty acid composition. Erythrocyte phosphatidylethanolamine and phosphatidylcholine fatty acid compositions were also investigated in their term infants, breast-fed over a period of 6 weeks. Fatty acid composition (g/100 g) of all samples was determined by GLC and anthropometric measurements were assessed in the two populations at birth and on day 42. Comparisons of white adipose tissue fatty acid compositions demonstrated lower levels of saturated (23·64 (se 1·54) v. 29·75 (se 0·67), P < 0·01) and monounsaturated (39·44 (se 1·27) v. 54·84 (se 0·75), P < 0·001) fatty acids and higher levels of polyunsaturated fatty acids (n−6 series: 32·47 (se 1·31) v. 14·32 (se 0·47), P < 0·001 and n−3 series: 2·87 (se 0·49) v. 0·80 (se 0·07), P < 0·01) in Mauritian than in French samples respectively. Accordingly, milk fat of the Mauritian women contained higher levels of parent essential fatty acids and their longer-chain derivatives than did milk fat from French women. Higher levels of parent essential fatty acids but lower levels of long-chain polyunsaturated fatty acids were found in erythrocyte phospholipids of Mauritian infants compared with French infants. Infants' erythrocyte arachidonate and docosahexaenoate contents did not correlate with any anthropometric variables at birth or at day 42, neither did they correlate with anthropometric variation over the study period. Our results suggest the lack of a simple relationship between the amount of long-chain polyunsaturated fatty acids in human milk and their accretion in the erythrocyte phospholipids of breast-fed infants when provided concomitantly with high levels of both linoleic and α-linolenic acids in ratios which fall within recommended ranges.
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21
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The implications of condensed tannins on the nutritive value of temperate forages fed to ruminants. Br J Nutr 2007. [DOI: 10.1017/s0007114599000501] [Citation(s) in RCA: 323] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Heird WC. Biochemical homeostasis and body growth are reliable end points in clinical nutrition trials. Proc Nutr Soc 2007; 64:297-303. [PMID: 16048660 DOI: 10.1079/pns2005435] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Studies of biochemical homeostasis and/or body growth have been included as outcome variables in most nutrition trials in paediatric patients. Moreover, these outcome variables have provided important insights into the nutrient requirements of infants and children, and continue to do so. Examples of the value of such studies in improving parenteral nutrition, in defining essential fatty acid metabolism and requirements of infants and in defining the protein and energy needs of low-birth-weight infants are discussed. Data from such studies have helped to define the mechanism of metabolic acidosis and hyperammonaemia associated with the use of early crystalline amino acid mixture and, hence, how to prevent these disorders. Such studies have allowed the development of parenteral amino acid mixtures that circumvent grossly abnormal plasma concentrations of most amino acids and appear to be utilized more efficiently. These studies have also helped define micronutrient requirements, including requirements for several such nutrients that had not been previously recognized as essential (e.g. Cr, Se, Mo, α-linolenic acid). Studies of body growth have been particularly valuable in defining the nutritional requirements of low-birth-weight infants. Finally, studies of metabolic homeostasis coupled with more sophisticated metabolic studies have provided considerable insight into the metabolism of the essential fatty acids, linoleic acid (18:2n-6) and α-linolenic acid (18:3n-3). Although such studies have not defined the amount of the longer-chain PUFA synthesized from each of these essential fatty acids, i.e. arachidonic acid (20:4n-6) and DHA (22:6n-3), they have shown that the rates of conversion are extremely variable from infant to infant, suggesting a possible explanation of why some studies show developmental advantages from intake of these fatty acids while others do not.
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Affiliation(s)
- William C Heird
- Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX 77030, USA.
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Wright K, Coverston C, Tiedeman M, Abegglen JA. Formula supplemented with docosahexaenoic acid (DHA) and arachidonic acid (ARA): a critical review of the research. J SPEC PEDIATR NURS 2006; 11:100-12; discussion 112-3. [PMID: 16635189 DOI: 10.1111/j.1744-6155.2006.00048.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To summarize results of randomized controlled trials (RCTs) evaluating growth, cognitive, neurological, and visual development of term infants supplemented with docosahexaenoic acid (DHA) and arachidonic acid (ARA). DESIGN AND METHODS The Boyack and Lookinland Methodological Quality Index (MQI) was used to evaluate data from RCTs identified from multiple data bases. RESULTS Six of ten studies found the addition of DHA and ARA to have no significant effect on infant development. PRACTICE IMPLICATIONS More expensive formula with endogenous DHA and ARA is not necessary. Results from longer studies currently underway will be beneficial.
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Langelier B, Alessandri JM, Perruchot MH, Guesnet P, Lavialle M. Changes of the transcriptional and fatty acid profiles in response to n-3 fatty acids in SH-SY5Y neuroblastoma cells. Lipids 2006; 40:719-28. [PMID: 16196423 DOI: 10.1007/s11745-005-1435-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Synthesis of docosahexaenoic acid (DHA) from its metabolic precursors contributes to membrane incorporation of this FA within the central nervous system. Although cultured neural cells are able to produce DHA, the membrane DHA contents resulting from metabolic conversion do not match the high values of those resulting from supplementation with preformed DHA. We have examined whether the DHA precursors down-regulate the incorporation of newly formed DHA within human neuroblastoma cells. SH-SY5Y cells were incubated with gradual doses of alpha-linolenic acid (alpha-LNA), EPA, or docosapentaenoic acid (DPA), and the incorporation of DHA into ethanolamine glycerophospholipids was analyzed as a reflection of synthesizing activity. The incorporation of EPA, DPA, and preformed DHA followed a dose-response saturating curve, whereas that of DHA synthesized either from alpha-LNA, EPA, or DPA peaked at concentrations of precursors below 15-30 microM and sharply decreased with higher doses. The mRNA encoding for six FA metabolism genes were quantified using real-time PCR. Two enzymes of the peroxisomal beta-oxidation, L-bifunctional protein and peroxisomal acyl-CoA oxidase, were expressed at lower levels than fatty acyl-CoA ligase 3 (FACL3) and delta6-desaturase (delta6-D). The delta6-D mRNA slightly increased between 16 and 48 h of culture, and this effect was abolished in the presence of 70 microM EPA. In contrast, the EPA treatment resulted in a time-dependent increase of FACL3 mRNA. The terminal step of DHA synthesis seems to form a "metabolic bottleneck," resulting in accretion of EPA and DPA when the precursor concentration exceeds a specific threshold value. We conclude that the critical precursor- concentration window of responsiveness may originate from the low basal expression level of peroxisomal enzymes.
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Affiliation(s)
- Bénédicte Langelier
- Nutrition & Food Safety, Neurobiology of Lipids, INRA (l'Institut National de la Recherche Agronomique), Jouy-en-Josas, France
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Fleith M, Clandinin MT. Dietary PUFA for preterm and term infants: review of clinical studies. Crit Rev Food Sci Nutr 2005; 45:205-29. [PMID: 16048149 DOI: 10.1080/10408690590956378] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Human milk contains n-3 and n-6 LCPUFA (long chain polyunsaturated fatty acids), which are absent from many infant formulas. During neonatal life, there is a rapid accretion of AA (arachidonic acid) and DHA (docosahexaenoic acid) in infant brain, DHA in retina and of AA in the whole body. The DHA status of breast-fed infants is higher than that of formula-fed infants when formulas do not contain LCPUFA. Studies report that visual acuity of breast-fed infants is better than that of formula-fed infants, but other studies do not find a difference. Cognitive development of breast-fed infants is generally better, but many sociocultural confounding factors may also contribute to these differences. The effect of dietary LCPUFA on FA status, immune function, visual, cognitive, and motor functions has been evaluated in preterm and term infants. Plasma and RBC FA status of infants fed formulas supplemented with both n-3 and n-6 LCPUFA was closer to the status of breast-fed infants than to that of infants fed formulas containing no LCPUFA. Adding n-3 LCPUFA to preterm-infant formulas led to initial beneficial effects on visual acuity. Few data are available on cognitive function, but it seems that in preterm infants, feeding n-3 LCPUFA improved visual attention and cognitive development compared with infants receiving no LCPUFA. Term infants need an exogenous supply of AA and DHA to achieve similar accretion of fatty acid in plasma and RBC (red blood cell) in comparison to breast-fed infants. Fewer than half of all studies have found beneficial effects of LCPUFA on visual, mental, or psychomotor functions. Improved developmental scores at 18 mo of age have been reported for infants fed both AA and DHA. Growth, body weight, and anthropometrics of preterm and term infants fed formulas providing both n-3 and n-6 LCPUFA fatty acids is similar in most studies to that of infants fed formulas containing no LCPUFA. A larger double-blind multicenter randomized study has recently demonstrated improved growth and developmental scores in a long-term feeding study of preterm infants. Collectively, the body of literature suggests that LCPUFA is important to the growth and development of infants. Thus, for preterm infants we recommend LCPUFA intakes in the range provided by feeding of human milk typical of mothers in Western countries. This range can be achieved by a combination of AA and DHA, providing an AA to DHA ratio of approximately 1.5 and a DHA content of as much as 0.4%. Preterm infants may benefit from slightly higher levels of these fatty acids than term infants. In long-term studies, feeding more than 0.2% DHA and 0.3% AA improved the status of these fatty acids for many weeks after DHA; AA was no longer present in the formula, enabling a DHA and AA status more similar to that of infants fed human milk. The addition of LCPUFA in infant formulas for term infants, with appropriate regard for quantitative and qualitative qualities, is safe and will enable the formula-fed infant to achieve the same blood LCPUFA status as that of the breast-fed infant.
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Affiliation(s)
- M Fleith
- Nestle Research Center, Lausanne, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
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Abstract
The presence of docosahexaenoic acid (DHA) and arachidonic acid (ARA) in human milk but not in infant formula, coupled with lower plasma and brain lipid contents of DHA in formula-fed than in breast-fed infants and reports of higher IQ in individuals who were breast-fed versus formula-fed as infants, suggest that exogenous DHA (and ARA) may be essential for optimal development. Thus, since 1990, several studies have examined the impact of formulas containing DHA or DHA plus ARA on visual function and neurodevelopmental outcome. Some of these studies have shown benefits but others have not. These results leave largely unanswered the question of whether these fatty acids are beneficial for either the term or preterm infant. However, evidence that preterm infants might benefit is somewhat more convincing than that for term infants. Despite the limited evidence for efficacy, formulas supplemented with DHA and ARA are now available and appear to be safe.
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Affiliation(s)
- William C Heird
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030-2600, USA.
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Makrides M, Gibson RA, Udell T, Ried K. Supplementation of infant formula with long-chain polyunsaturated fatty acids does not influence the growth of term infants. Am J Clin Nutr 2005; 81:1094-101. [PMID: 15883434 DOI: 10.1093/ajcn/81.5.1094] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Adequate growth is an important indicator of health and well-being in infants. OBJECTIVE Our objective was to determine the effect of supplementing infant formula with long-chain polyunsaturated fatty acids (LCPUFAs) on the growth of term infants. DESIGN Using the methodology outlined by the Cochrane Collaboration, we reviewed all known randomized controlled trials that involved LCPUFA supplementation of infant formula fed to term infants. Outcome measures were weight, length, and head circumference. Original data obtained from the investigators of published trials were used. Outcomes were analyzed with fixed-effects or random-effects model meta-analyses and were reported as weighted mean differences with 95% CIs. RESULTS We identified 14 eligible trials that had data available for meta-analysis (1846 infants). Trial quality was generally high. Meta-analysis showed no significant effect of LCPUFA supplementation on infant weight, length, or head circumference at any assessment age. Similarly, subgroup analyses showed that supplementation with only n-3 LCPUFAs (no arachidonic acid) had no significant effect on infant weight, length, or head circumference. The source of LCPUFA supplementation (phospholipid or triacylglycerol) also did not significantly affect infant growth. CONCLUSION We found no evidence that LCPUFA supplementation of infant formula influences the growth of term infants in either a positive or a negative way.
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Affiliation(s)
- Maria Makrides
- Applied Nutrition Group, Child Health Research Institute, Women's and Children's Hospital, North Adelaide, SA, Australia.
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Georgieff MK, Innis SM. Controversial nutrients that potentially affect preterm neurodevelopment: essential fatty acids and iron. Pediatr Res 2005; 57:99R-103R. [PMID: 15817493 DOI: 10.1203/01.pdr.0000160542.69840.0f] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Innis S. Chapter 10 Essential fatty acid metabolism during early development. BIOLOGY OF GROWING ANIMALS 2005. [DOI: 10.1016/s1877-1823(09)70017-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Udell T, Gibson RA, Makrides M. The effect of α-linolenic acid and linoleic acid on the growth and development of formula-fed infants: A systematic review and meta-analysis of randomized controlled trials. Lipids 2005; 40:1-11. [PMID: 15825825 DOI: 10.1007/s11745-005-1354-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This systematic review and meta-analysis aimed to evaluate the effect of modifying 18-carbon PUFA [18-C PUFA: alpha-linolenic acid (ALA, 18:3n-3) and linoleic acid (LA, 18:2n-6)] in the diets of term and preterm infants on DHA (22:6n-3) status, growth, and developmental outcomes. Only randomized controlled trials (RCT) involving formula-fed term and preterm infants, in which the 18-C PUFA composition of the formula was changed and growth or developmental outcomes were measured, were included. Differences were presented as control (standard formula) and treatment (18-C PUFA-supplemented formula). Primary analyses for term infants were 4 and 12 mon and for preterm infants 37-42 and 57 wk postmenstrual age. Five RCT involving term infants and three RCT involving preterm infants were included in the systematic review. Infants fed ALA-supplemented formula had significantly higher plasma and erythrocyte phospholipid DHA levels than control infants. There was no effect of ALA supplementation on the growth of preterm infants. In term infants, ALA supplementation was associated with increased weight and length at 12 mon, which was at least 4 mon after the end of dietary intervention. Developmental indices of term infants did not differ between groups. There was a transient improvement in the retinal function of preterm infants fed ALA-supplemented diets compared with controls. The findings suggest that ALA-supplemented diets improve the DHA status of infants. Further studies are needed to provide convincing evidence regarding the effects of ALA supplementation of formula on infant growth and development.
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Affiliation(s)
- Tuesday Udell
- Department of Paediatrics & Child Health, Flinders University, Bedford Park, South Australia, Australia
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31
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Innis SM, Vaghri Z, King DJ. n-6 Docosapentaenoic acid is not a predictor of low docosahexaenoic acid status in Canadian preschool children. Am J Clin Nutr 2004; 80:768-73. [PMID: 15321820 DOI: 10.1093/ajcn/80.3.768] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The n-3 fatty acid docosahexaenoic acid (DHA; 22:6n-3) is important for neural and visual functional development. In animals, 22:6n-3 deficiency is accompanied by increased docosapentaenoic acid (DPA; 22:5n-6), which suggests that the ratio of 22:6n-3 to 22:5n-6 could be a useful biochemical marker of low n-3 fatty acid status. The n-3 fatty acid status of preschool children has not been described, and data are lacking on whether low 22:6n-3 is accompanied by high 22:5n-6 in humans. OBJECTIVE We determined n-3 fatty acid status and investigated the relation between 22:6n-3 and 22:5n-6 in children. DESIGN In Canadian children aged 18-60 mo (n = 84), the n-3 and n-6 fatty acid status of erythrocyte phosphatidylethanolamine was measured, and dietary fat intake was estimated by using a food-frequency questionnaire. RESULTS The mean (+/- SEM) 22:6n-3 concentration in erythrocyte phosphatidylethanolamine among children was 3.06 +/- 0.13 g/100 g fatty acids (5th-95th percentiles: 1.43-5.79 g/100 g fatty acids). Concentrations of 22:5n-6 increased with increasing 22:6n-3 concentrations in erythrocyte phosphatidylethanolamine (P < 0.01). Mean intakes of linoleic acid (18:2n-6), linolenic acid (18:3n-3), and trans fatty acids were 3.6 +/- 0.2%, 0.7 +/- 0.5%, and 2.0 +/- 1.3%, respectively. Phosphatidylethanolamine 22:6n-3 and 22:5n-3 concentrations were inversely related to the intakes of 18:2n-6 and trans fatty acids, but not to those of total fat or n-3 fatty acids. CONCLUSIONS The concentration of 22:5n-6 is not a useful biochemical marker of low n-3 fatty acid intake or status in the membrane phosphatidylethanolamine of preschool children. High intakes of 18:2n-6 and trans fatty acids could compromise the incorporation of 22:6n-3 into membrane phospholipids.
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Affiliation(s)
- Sheila M Innis
- Nutrition Research Program, British Columbia Research Institute for Children's and Women's Health, University of British Columbia, 950 West 28th Avenue, Vancouver, BC V5Z 4H4, Canada.
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Sarkadi-Nagy E, Wijendran V, Diau GY, Chao AC, Hsieh AT, Turpeinen A, Lawrence P, Nathanielsz PW, Brenna JT. Formula feeding potentiates docosahexaenoic and arachidonic acid biosynthesis in term and preterm baboon neonates. J Lipid Res 2004; 45:71-80. [PMID: 14523049 DOI: 10.1194/jlr.m300106-jlr200] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Infant formulas supplemented with docosahexaenoic acid (DHA) and arachidonic acid (ARA) are now available in the United States; however, little is known about the factors that affect biosynthesis. Baboon neonates were assigned to one of four treatments: term, breast-fed; term, formula-fed; preterm (155 of 182 days gestation), formula-fed; and preterm, formula+DHA/ARA-fed. Standard formula had no DHA/ARA; supplemented formula had 0.61%wt DHA (0.3% of calories) and 1.21%wt ARA (0.6% of calories), and baboon breast milk contained 0.68 +/- 0.22%wt DHA and 0.62 +/- 0.12%wt ARA. At 14 days adjusted age, neonates received a combined oral dose of [U-13C]alpha-linolenic acid (LNA*) and [U-13C]linoleic acid (LA*), and tissues were analyzed 14 days after dose. Brain accretion of linolenic acid-derived DHA was approximately 3-fold greater for the formula groups than for the breast-fed group, and dietary DHA partially attenuated excess DHA synthesis among preterms. A similar, significant pattern was found in other organs. Brain linoleic acid-derived ARA accretion was significantly greater in the unsupplemented term group but not in the preterm groups compared with the breast-fed group. These data show that formula potentiates the biosynthesis/accretion of DHA/ARA in term and preterm neonates compared with breast-fed neonates and that the inclusion of DHA/ARA in preterm formula partially restores DHA/ARA biosynthesis to lower, breast-fed levels. Current formula DHA concentrations are inadequate to normalize long-chain polyunsaturated fatty acids synthesis to that of breast-fed levels.
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Affiliation(s)
- Eszter Sarkadi-Nagy
- Division of Nutritional Sciences, Savage Hall, Cornell University, Ithaca, NY 14853
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Innis SM. Polyunsaturated Fatty Acids in Human Milk. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2004; 554:27-43. [PMID: 15384565 DOI: 10.1007/978-1-4757-4242-8_5] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The n-6 and n-3 fatty acids are essential dietary nutrients required for optimal growth and development, particularly of the brain and retina. Large amounts of the n-3 fatty acid docosahexaenoic acid (DHA) is accumulated in the brain grey matter and the visual elements of the retina during development, and reduced DHA in these tissues can result in decreased visual and psychomotor development. Although the possible importance of differences in n-6 and n-3 fatty acids, particularly DHA, between human milk and infant formulas has been the subject of intense clinical research, the variability in the essential fatty acid content of milk within and among different populations of women and implications of this to infant growth and development have received much less attention. Considerable research has shown that the DHA content of the maternal diet is the most important determinant of the amount of DHA secreted in milk, and thus the dietary intake of the breastfed infant. The DHA content of human milk varies over 10-fold, being lowest in women with no intake of DHA and highest in women with high intakes of DHA, which is found predominantly in fatty fish. The requirement for n-3 fatty acids, and the balance of n-6 and n-3 fatty acids for optimal growth and development of the brain and retina, and long-term minimization of risk of chronic disease remains as one of the most important questions in infant nutrition. Dietary recommendations to modifying dietary fat with the aim of reducing risk of chronic disease, including obesity and cardiovascular disease in adults, need to consider that when followed by pregnant women, these recommendations can have a marked effect on the amount and balance of n-6 and n-3 fatty acids secreted in milk.
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MESH Headings
- Brain/growth & development
- Brain/metabolism
- Child Development
- Docosahexaenoic Acids
- Fatty Acids, Omega-3/administration & dosage
- Fatty Acids, Omega-3/metabolism
- Fatty Acids, Omega-3/physiology
- Fatty Acids, Omega-6/administration & dosage
- Fatty Acids, Omega-6/metabolism
- Fatty Acids, Omega-6/physiology
- Fatty Acids, Unsaturated/administration & dosage
- Fatty Acids, Unsaturated/metabolism
- Fatty Acids, Unsaturated/physiology
- Humans
- Infant
- Infant Formula/chemistry
- Infant Nutritional Physiological Phenomena
- Infant, Newborn
- Lactation
- Milk, Human/chemistry
- Milk, Human/metabolism
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Affiliation(s)
- Sheila M Innis
- Department of Paediatrics, BC Research Institute for Children's and Women's Health, University of British Columbia, Vancouver, BC, Canada V5Z, 4H4.
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Abstract
Docosahexaenoic acid (DHA) and arachidonic acid (ARA) are important structural components of the central nervous system. These fatty acids are transferred across the placenta, are present in human milk, and are accumulated in the brain and retina during fetal and infant development. The high concentrations of DHA in the retina and of DHA and ARA in brain gray matter suggests that these fatty acids have important roles in retinal and neural function. Animal studies have shown that depletion of DHA from the retina and brain results in reduced visual function and learning deficits. The latter effects may be explained by changes in the membrane bilayer that alter membrane-associated receptors and signal transduction systems, ion channel activity, or direct effects on gene expression. DHA can be formed in the liver from alpha linolenic acid, but it is unclear if the rate of DHA synthesis in humans is sufficient to support optimal brain and retinal development. Although there is no evidence that the ability to form ARA from linoleic acid is limiting, supplementation with DHA reduces tissue ARA, possibly creating a conditional need for ARA in infants with a dietary intake of DHA. The amount of DHA in human milk varies widely and is positively correlated with visual and language development in breast-fed infants. Advances in understanding essential fatty acid requirements will benefit from intervention studies that use functionally relevant tests to probe the deficiency or adequacy of physiologically important pools of DHA and ARA in developing infants.
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Affiliation(s)
- Sheila M Innis
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
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35
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Hoffman DR, Birch EE, Castañeda YS, Fawcett SL, Wheaton DH, Birch DG, Uauy R. Visual function in breast-fed term infants weaned to formula with or without long-chain polyunsaturates at 4 to 6 months: a randomized clinical trial. J Pediatr 2003; 142:669-77. [PMID: 12838196 DOI: 10.1067/mpd.2003.213] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Breast-fed infants receive docosahexaenoic acid (DHA) and arachidonic acid (ARA) in their diet. Upon weaning, infants lose this dietary source of long-chain polyunsaturates because many commercial formulas do not contain these important constituents for neural membrane biogenesis. We evaluated the benefits of postweaning dietary supplementation of DHA + ARA on visual maturation. STUDY DESIGN Healthy term infants (n = 61) were breast-fed to 4 to 6 months, then were randomly assigned to commercial formula or formula supplemented with DHA (0.36%) + ARA (0.72%). Measurements of red blood cell (RBC) fatty acids, visually evoked potential (VEP) acuity, and stereoacuity were done before and after weaning. RESULTS At 1 year of age, RBC-DHA in the commercial formula-fed group was reduced by 50% from the weaning level, whereas there was a 24% increase in the DHA + ARA-supplemented group. The primary outcome measure, VEP acuity, was significantly more mature in supplemented infants at 1 year of age. Elevated RBC-DHA levels were associated with more mature VEP acuity. There were no significant diet-related differences in stereoacuity. CONCLUSIONS These data extend through the first year of life the critical period in which a dietary supply of DHA and ARA can contribute in optimizing visual development in term infants.
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36
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Innis SM, Elias SL. Intakes of essential n-6 and n-3 polyunsaturated fatty acids among pregnant Canadian women. Am J Clin Nutr 2003; 77:473-8. [PMID: 12540410 DOI: 10.1093/ajcn/77.2.473] [Citation(s) in RCA: 136] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Fetal growth requires n-3 docosahexaenoic acid (DHA), which is derived from the essential n-3 fatty acids in the maternal diet. DHA is accumulated in the developing brain and is critical for normal neural and visual function. Available estimates suggest that 67 mg DHA/d is accumulated by the fetus during the third trimester of gestation. Little is known about n-3 fatty acid intakes in pregnant women, although human milk concentrations of DHA have decreased in recent years. OBJECTIVE We prospectively determined the n-3 and n-6 fatty acid intakes of 55 pregnant Canadian women. DESIGN A food-frequency questionnaire was completed at 28 and 35 wk, and plasma n-3 and n-6 fatty acids were measured at 35 wk gestation. The fatty acid composition of approximately 500 foods was analyzed to allow analysis of dietary intakes from specific foods. RESULTS Intakes, as a percentage of energy, were (macro x +/- SEM) total fat, 28.0 +/- 3.6%; saturated fat, 9.8 +/- 0.3%; monounsaturated fat, 11.2 +/- 0.4%; polyunsaturated fat, 4.7 +/- 0.2%; linoleic acid, 3.9 +/- 0.2%; and alpha-linolenic acid, 0.54 +/- 0.05%. The daily intakes (range) were 160 +/- 20 (24-524) mg DHA/d, 121 +/- 8 (15-301) mg arachidonic acid/d, and 78 +/- 2 (4-125) mg eicosapentaenoic acid/d. The plasma phospholipids had (mg/100 g fatty acid) 5.0 +/- 0.18 DHA, 8.7 +/- 0.18 arachidonic acid, and 0.52 +/- 0.32 eicosapentaenoic acid. CONCLUSION The low intake of DHA among some pregnant women highlights the need for studies to address the functional significance of maternal fat intakes during pregnancy on fetal development.
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Affiliation(s)
- Sheila M Innis
- Department of Pediatrics, University of British Columbia, Vancouver, Canada.
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Abstract
In addition to their role as a source of energy, several fatty acids are important components of cell membranes and/or precursors of biologically important eicosanoids. The long-chain polyunsaturated fatty acids, docosahexaenoic acid (DHA) and arachidonic acid (AA), are important for optimal visual function and neurodevelopment. These fatty acids are present in human milk but, until recently, have not been included in formulas marketed in the United States. Although the results of clinical trials assessing the effect of DHA and AA intakes on visual and cognitive development have been inconsistent, some studies suggest benefits. Adequate intake of these fatty acids may be especially important for the preterm infant.
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Affiliation(s)
- Craig L Jensen
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, 1100 Bates Street, Houston, TX 77030, USA.
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38
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Abstract
Achieving appropriate growth and nutrient accretion of preterm and low birth weight (LBW) infants is often difficult during hospitalization because of metabolic and gastrointestinal immaturity and other complicating medical conditions. Advances in the care of preterm-LBW infants, including improved nutrition, have reduced mortality rates for these infants from 9.6 to 6.2% from 1983 to 1997. The Food and Drug Administration (FDA) has responsibility for ensuring the safety and nutritional quality of infant formulas based on current scientific knowledge. Consequently, under FDA contract, an ad hoc Expert Panel was convened by the Life Sciences Research Office of the American Society for Nutritional Sciences to make recommendations for the nutrient content of formulas for preterm-LBW infants based on current scientific knowledge and expert opinion. Recommendations were developed from different criteria than that used for recommendations for term infant formula. To ensure nutrient adequacy, the Panel considered intrauterine accretion rate, organ development, factorial estimates of requirements, nutrient interactions and supplemental feeding studies. Consideration was also given to long-term developmental outcome. Some recommendations were based on current use in domestic preterm formula. Included were recommendations for nutrients not required in formula for term infants such as lactose and arginine. Recommendations, examples, and sample calculations were based on a 1000 g preterm infant consuming 120 kcal/kg and 150 mL/d of an 810 kcal/L formula. A summary of recommendations for energy and 45 nutrient components of enteral formulas for preterm-LBW infants are presented. Recommendations for five nutrient:nutrient ratios are also presented. In addition, critical areas for future research on the nutritional requirements specific for preterm-LBW infants are identified.
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Affiliation(s)
- Catherine J Klein
- Life Sciences Research Office, 9650 Rockville Pike, Bethesda, Maryland 20814, USA.
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Voigt RG, Jensen CL, Fraley JK, Rozelle JC, Brown FR, Heird WC. Relationship between omega3 long-chain polyunsaturated fatty acid status during early infancy and neurodevelopmental status at 1 year of age. J Hum Nutr Diet 2002; 15:111-20. [PMID: 11972740 DOI: 10.1046/j.1365-277x.2002.00341.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the influence of alpha-linolenic acid (ALA; 18 : 3omega3) intake and, hence, the influence of plasma and/or erythrocyte phospholipid content of docosahexaenoic acid (DHA; 22 : 6omega3) during early infancy on neurodevelopmental outcome of term infants. METHODS The Bayley Scales of Infant Development (second edition), the Clinical Adaptive Test/Clinical Linguistic and Auditory Milestone Scale (CAT/CLAMS) and the Gross Motor Scale of the Revised Gesell Developmental Inventory were administered at a mean age of 12.26 +/- 0.94 months to 44 normal term infants enrolled in a study evaluating the effects of infant formulas differing only in ALA content (0.4, 1.0, 1.7 and 3.2% of total fatty acids). RESULTS As reported previously [Jensen et al., Lipids 13 (1996) 107; J. Pediatr. 131 (1997) 200], the group fed the formula with the lowest ALA content had the lowest mean plasma and erythrocyte phospholipid DHA contents at 4 months of age. This group also had the lowest mean score on every neurodevelopmental measure. The difference in mean gross motor developmental quotient of this group versus the group fed the formula with 1.0% ALA but not of the other groups was statistically significant (P < 0.05). Across the groups, motor indices correlated positively with each other and with the plasma phospholipid DHA content at 4 months of age (P=0.02-0.03). The CLAMS developmental quotient correlated with the erythrocyte phospholipid content of 20 : 5omega3 (P < 0.01) but not with DHA. CONCLUSIONS These statistically significant correlations suggest that the omega3 fatty acid status during early infancy may be important with respect to neurodevelopmental status at 1 year of age and highlight the need for further studies of this possibility.
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Affiliation(s)
- R G Voigt
- Meyer Center for Developmental Pediatrics, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
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40
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Gibson RA, Chen W, Makrides M. Randomized trials with polyunsaturated fatty acid interventions in preterm and term infants: functional and clinical outcomes. Lipids 2001; 36:873-83. [PMID: 11724459 DOI: 10.1007/s11745-001-0797-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The role of polyunsaturated fatty acids (PUFA) in infant nutrition has now been well studied through many randomized controlled trials (RCT) that provide us with high-quality evidence, particularly in relation to efficacy. As a result of a systematic search of the literature for RCT of supplementation of formulas of term and preterm infants with long-chain polyunsaturated fatty acids (LC-PUFA), we have identified 21 studies that have physiological responses or growth as outcomes. There have been 11 RCT involving preterm infants, and many of these claim a beneficial effect on visual, neural, or developmental outcomes. There are some reports of negative effects on growth in relation to the addition of n-3 LC-PUFA to preterm formulas but not when AA is added with n-3 LC-PUFA. Small studies have shown no differences in prostanoid formation or peroxidative stress between n-3 LC-PUFA-supplemented and unsupplemented infants. There have been 10 RCT involving term infants; whereas some studies report an effect on visual/neural/developmental outcomes, an equal number report no effect. There have been no reports of negative effects of n-3 LC-PUFA on growth in term infants. In summary, there appear to be few safety concerns relating to the use of LC-PUFA in infant nutrition. The potential medium- and long-term effects of including these compounds in the early diet of infants remain to be assessed.
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Affiliation(s)
- R A Gibson
- Child Health Research Institute at Flinders Centre and Women's & Children's Hospital, Adelaide, SA, Australia.
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41
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Abstract
The relationship between polyunsaturated longchain fatty acids and atopy has been discussed for decades. Higher levels of the essential fatty acids linoleic acid and alpha-linolenic acid and lower levels of their longer metabolites in plasma phospholipids of atopic as compared to nonatopic individuals have been reported by several, but not all, studies. Largely similar findings have been reported in studies of cell membranes from immunological cells from atopics and non-atopics despite differences in methodology, study groups, and definitions of atopy. An imbalance in the metabolism of the n-6 fatty acids, particularly arachidonic acid and dihomo-gamma-linolenic acid, leading to an inappropriate synthesis of prostaglandin (PG) E2 and PGE1 was hypothesized early on but has not been corroborated. The fatty acid composition of human milk is dependent on the time of lactation not only during a breast meal but also the time of the day and the period of lactation. This explains the discrepancies in reported findings regarding the relationship between milk fatty acids and atopic disease in the mother. Prospective studies show disturbances in both the n-6 and n-3 fatty acid composition between milk from atopic and nonatopic mothers. Only the composition of long-chain polyunsaturated n-3 fatty acids was related to atopic development in the children, however. A relationship between lower levels of n-3 fatty acids, particularly eicosapentaenoic acid (20:5 n-3), and early development of atopic disease is hypothesized.
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Affiliation(s)
- K Duchén
- Division of Pediatrics, Department of Health and Environment, Linkoping University Hospital, Linkoping, Sweden.
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42
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Abstract
Because of the rapid rate of growth during infancy, and the potentially deleterious effect of differences in the availability of dietary essential nutrients, growth is an important outcome variable in any study assessing a diet designed for infants. Nearly 10 yr after the first demonstration of reduced growth in preterm infants fed a fish oil-enriched formula, there is very little additional information to confirm or refute the finding that long-chain n-3 polyunsaturated fatty acid (LC-PUFA) intake can modulate growth in infants. To evaluate the issue of a possible relationship between PUFA intake and growth of infants, we reviewed a total of 32 randomized studies, 13 in preterm infants and 19 in term infants. From the data published to date, it seems clear that long-chain n-3 fatty acids can reduce growth achievement in preterm and term infants under some experimental conditions. However, the effect of n-3 PUFA supplementation on the growth of preterm and term infants appears to be minimal and of questionable clinical and/or physiologic relevance. Nonetheless, n-3 fatty acids have an effect on gene transcription, at least in some species, and this finding may provide important clues to the mechanism by which n-3 and n-6 fatty acids regulate growth.
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Affiliation(s)
- A Lapillonne
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
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43
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Duchén K. Are human milk polyunsaturated fatty acids (PUFA) related to atopy in the mother and her child? Allergy 2001; 56:587-92. [PMID: 11421915 DOI: 10.1034/j.1398-9995.2001.00040.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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44
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Infante JP, Huszagh VA. Impaired arachidonic (20:4n-6) and docosahexaenoic (22:6n-3) acid synthesis by phenylalanine metabolites as etiological factors in the neuropathology of phenylketonuria. Mol Genet Metab 2001; 72:185-98. [PMID: 11243724 DOI: 10.1006/mgme.2001.3148] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The recent literature on polyunsaturated fatty acid metabolism in phenylketonuria (PKU) is critically analyzed. The data suggest that developmental impairment of the accretion of brain arachidonic (20:4n-6) and docosahexaenoic (22:6n-3, DHA) acids is a major etiological factor in the microcephaly and mental retardation of uncontrolled PKU and maternal PKU. These fatty acids appear to be synthesized by the recently elucidated carnitine-dependent, channeled, mitochondrial fatty acid desaturases for which alpha-tocopherolquinone (alpha-TQ) is an essential enzyme cofactor. alpha-TQ can be synthesized either de novo or from alpha-tocopherol. The fetus and newborn would primarily rely on de novo alpha-TQ synthesis for these mitochondrial desaturases because of low maternal transfer of alpha-tocopherol. Homogentisate, a pivotal intermediate in the de novo pathway of alpha-TQ synthesis, is synthesized by 4-hydroxyphenylpyruvate dioxygenase. The major catabolic products of excess phenylalanine, viz. phenylpyruvate and phenyllactate, are proposed to inhibit alpha-TQ synthesis at the level of the dioxygenase reaction by competing with its 4-hydroxyphenylpyruvate substrate, thus leading to a developmental impairment of 20:4n-6 and 22:6n-3 synthesis in uncontrolled PKU and fetuses of PKU mothers. The data suggest that dietary supplementation with carnitine, 20:4n-6, and 22:6n-3 may have therapeutic value for PKU mothers and for PKU patients who have been shown to have a low plasma status of these essential metabolites.
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Affiliation(s)
- J P Infante
- Institute for Theoretical Biochemistry and Molecular Biology, Ithaca, New York 14852, USA.
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45
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Abstract
DHA and AA, which are components of breast milk but not infant formulas marketed in the United States and some other countries, are important components of the brain, and DHA is a major component of the retina. Also, many studies have demonstrated advantages of breastfeeding versus formula-feeding on subsequent cognitive and visual function; however, available data are insufficient to justify the conclusion that the presence of DHA and AA in breast milk is partially or soley responsible for the apparent advantages of breastfeeding. On the other hand, many studies of DHA (and AA)-supplemented versus unsupplemented formulas have shown clear advantages of the supplemented formulas on visual acuity at 2 and 4 months of age or neurodevelopmental status at 12 to 18 months of age. Although one logically may assume that these early effects may have long-term effects, this assumption is not warranted by the available data. One of the major problems is the difficulty of assessing visual and cognitive function of infants. Scores on standard neurodevelopmental tests at 1 year of age, for example, are only weakly correlated with performance at school age (when more definitive assessments are possible), and little is known about the predictability of later visual function from behavioral or electrophysiologic assessments of visual function early in life. Even prematurely born infants can synthesize DHA and AA and other omega-3 and omega-6 LC-PUFAs from the dietary EFAs, LA and ALA. Nonetheless, plasma, erythrocyte and brain lipid levels of DHA are lower in infants whose diets do not contain DHA. Whether more optimal intakes of ALA result in higher plasma and tissue levels of this FA is unclear. The breast-milk content of LC-PUFAs is not regulated by the mammary gland but, rather, reflects the concentrations of LC-PUFAs in maternal plasma lipids that, in turn, are dependent on maternal diet and, probably, maternal activities of the desaturases and elongases involved in converting dietary LA and ALA to LC-PUFAs. This occurrence suggests that some infants receive sufficient LC-PUFA to support normal rates of deposition, whereas others may not. Also, some infants probably can synthesize additional LC-PUFAs from the LA and ALA contents of human milk. Thus, depending on maternal diet and maternal and infant desaturase and elongase activities, some breastfed infants may receive less than adequate LC-PUFAs to support normal rates of deposition. Clearly, the role of LC-PUFAs in infant development is not a simple issue. Also, no foolproof method exists to ensure an adequate but not excessive intake. Thus, because some evidence shows that dietary LC-PUFA (DHA, AA, or both) as components of breast milk or formula confers at least transient developmental benefits, supplementation of infant formulas with LC-PUFAs is supportable provided that the supplements used are safe. The safety of all available supplements is unknown; however, some trials reveal few reasons for major concerns about the safety of single-cell oils, low-EPA fish oil, or egg-yolk phospholipid or triglyceride fractions.
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Affiliation(s)
- W C Heird
- Department of Pediatrics, Section of Nutrition, USDA/ARS Children's Nutrition Research Center, Baylor College of Medicine, Houston, Texas, USA
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Ramírez M, Gallardo EM, Souto AS, Weissheimer C, Gil A. Plasma fatty-acid composition and antioxidant capacity in low birth-weight infants fed formula enriched with n-6 and n-3 long-chain polyunsaturated fatty acids from purified phospholipids. Clin Nutr 2001; 20:69-76. [PMID: 11161546 DOI: 10.1054/clnu.2000.0163] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To determine whether a formula containing n-6 and n-3 long-chain polyunsaturated fatty acids (LCP) from purified phospholipids increases the content of 20:4n-6 and 22:6n-3 of plasma lipids and modifies the plasma antioxidant capacity in low-birth-weight infants. STUDY DESIGN Seventeen infants were fed a conventional formula for low birth-weight infants (F), and 17 a formula containing n-6 and n-3 LCP from purified pig-brain phospholipids (LCP-F). Fourteen infants receiving human milk from a human milk bank were used as a reference (HM). Growth index were measured and blood samples were taken at entry and after 15 days and 30 days of feeding. RESULTS In infants fed LCP-F the levels of 22:6n-3 in total plasma lipids and in plasma phospholipids and triglycerides were higher than in infants fed F and closer to the levels of HM group throughout the study. Docosahexaenoic acid concentration in total plasma lipids was 3.46+/-0.19 mg/dl in infants fed LCP-F and 2.08+/-0.20 in infants fed F after 15 days of feeding (P<0.001), and 3.83+/-0.30 and 2.15+/-0.20 in infants fed LCP-F and F respectively, after 30 days of feeding (P<0.001). The concentration of 20:4n-6 in the LCP-F was significantly higher than in the F group at 15 and 30 days of feeding. Plasma antioxidant capacity did not differ significantly between the study groups. CONCLUSION Feeding low birth-weight infants a formula containing LCP phospholipids results in an increase of n-3 and n-6 LCP in plasma towards that of infants fed human milk.
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MESH Headings
- Antioxidants/metabolism
- Fatty Acids/blood
- Fatty Acids/chemistry
- Fatty Acids, Omega-3/administration & dosage
- Fatty Acids, Omega-3/blood
- Fatty Acids, Omega-6
- Fatty Acids, Unsaturated/administration & dosage
- Fatty Acids, Unsaturated/blood
- Humans
- Infant Food
- Infant Nutritional Physiological Phenomena
- Infant, Low Birth Weight/blood
- Infant, Low Birth Weight/metabolism
- Infant, Newborn
- Infant, Premature
- Milk, Human
- Oxidation-Reduction
- Phospholipids/blood
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Affiliation(s)
- M Ramírez
- Clínicas de Porto Alegre Hospital, Porto Alegre, Brazil
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47
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Abstract
The fat requirements of children can be judged according to 4 criteria: 1) the possible obligate needs of fat as a metabolic fuel, 2) the provision of a sufficiently energy-dense diet to meet energy needs, 3) the adequate supply of essential fatty acids, and 4) the supply of sufficient fat to allow adequate absorption of fat-soluble vitamins. In these respects the fat requirements of children in developing countries are probably similar to those of children in affluent nations except for the additional needs imposed by environmental stresses, particularly recurrent infections. In many developing countries, the low energy density of weaning foods appears to be a major contributor to growth faltering and ultimate malnutrition. Evidence from doubly labeled water studies suggests that these diets are adequate when children are healthy but fail to support rapid catch-up growth after diarrhea and other infections. The issues in determining and meeting the fat needs of children in developing countries are illustrated with use of detailed comparative dietary data from a rural community in The Gambia and from Cambridge, United Kingdom. The outstanding feature of the Gambian data is the great importance of breast milk as a source of fat and essential fatty acids up until the end of the second year of life. Weaning foods and adult foods contain low amounts of fat, which causes a sharp transition from adequate fat intakes to probable inadequate fat intakes when children are weaned from the breast. The effects of such low fat intakes, particularly in terms of immune function, require investigation.
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Affiliation(s)
- A M Prentice
- MRC International Nutrition Group, London, and MRC Human Nutrition Research, Cambridge, United Kingdom.
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48
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Decsi T, Kelemen B, Minda H, Burus I, Kohn G. Effect of type of early infant feeding on fatty acid composition of plasma lipid classes in full-term infants during the second 6 months of life. J Pediatr Gastroenterol Nutr 2000; 30:547-51. [PMID: 10817286 DOI: 10.1097/00005176-200005000-00015] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND Previously, the authors found significantly higher arachidonic and docosahexaenoic acid values in plasma lipids in 2-month-old full-term infants fed human milk than in those receiving formula. This is the report of data obtained in full-term infants during the second half of the first year of life. METHODS Healthy, full-term infants fed human milk (n = 12) or formula without preformed long-chain polyunsaturated fatty acids (n = 12) were investigated. Fatty acid composition of plasma lipid classes was determined by high-resolution capillary gas-liquid chromatography. RESULTS Linoleic acid acid values in plasma phospholipids (18.5 [3.94] vs. 20.79 [4.34]) and gamma-linolenic acid values in plasma cholesteryl esters (0.17 [0.09] vs. 0.27 [0.20]) and triacylglycerols (0.27 [0.18] vs. 0.46 [0.27]) were significantly (P < 0.05) lower in breast-fed infants than in those receiving formula. Data are percentage weight by weight shown as median (range from 1st to 3rd quartile) for breast-fed vs. formula fed infants, respectively. In contrast, arachidonic acid values in plasma phospholipids (10.05 [2.90] vs. 7.03 [1.87]; P < 0.01), cholesteryl esters (7.54 [3.58] vs. 4.09 [1.81]; P < 0.05), and triacylglycerols (1.28 [0.84] vs. 0.80 [0.39]; P < 0.05), as well as docosahexaenoic acid values in plasma phospholipids (1.92 [0.36] vs. 1.02 [0.31]; P < 0.001), cholesteryl esters (0.39 [0.13] vs. 0.15 [0.13]; P < 0.001), and triacylglycerols (0.17 [0.17] vs. 0.09 [0.04]; P < 0.01) were significantly higher in infants fed human milk than in those receiving formula. CONCLUSION Healthy, full-term infants fed formula without preformed dietary long-chain polyunsaturated fatty acids are unable to match the arachidonic and docosahexaenoic acid status of breast-fed infants even during the second half of the first year of life.
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Affiliation(s)
- T Decsi
- Department of Paediatrics, University Medical School of Pécs, Hungary
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Duchén K, Casas R, Fagerås-Böttcher M, Yu G, Björkstén B. Human milk polyunsaturated long-chain fatty acids and secretory immunoglobulin A antibodies and early childhood allergy. Pediatr Allergy Immunol 2000; 11:29-39. [PMID: 10768733 DOI: 10.1034/j.1399-3038.2000.00052.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The possible protective effect of breast milk against atopic manifestations in infancy, i.e. atopic eczema and food allergy, has been controversial for the last decades. Besides the methodological problems, differences in the composition of human milk could explain these controversies. The aim of this study was to investigate the composition of polyunsaturated fatty acids (PUFA) and secretory immunoglobulin A (S-IgA) levels to food proteins (ovalbumin and beta-lactoglobulin) and an inhalant allergen (cat) in milk from mothers of allergic and non-allergic children. Blood samples were obtained at birth and at 3 months from 120 children. Skin prick tests were performed at 6, 12 and 18 months, and the development of atopic diseases was assessed in the children. Breast milk samples were collected from their mothers at birth and monthly during the lactation period. Milk PUFA composition was measured by gas chromatography, and enzyme-linked immunosorbent assay (ELISA) was used to measure total S-IgA, anti-cat S-IgA, anti-ovalbumin S-IgA, and anti-beta-lactoglobulin S-IgA. Allergic disease developed in 44/120 children (22/63 children of allergic mothers and 22/57 children of non-allergic mothers). Lower levels of eicosapentaenoic acid, C20:5 n-3 (EPA), docosapentaenoic acid C22:5 n-3 (DPA), and docosatetraenoic acid C22:4 n-6 (DHA) (p < 0.05 for all) were found in mature milk from mothers of allergic as compared to milk from mothers of non-allergic children. The total n-6:total n-3 and the arachidonic acid, C20:4 n-6 (AA):EPA ratios were significantly lower in transitional and mature milk from mothers of allergic children, as compared to milk from mothers of non-allergic children. The PUFA levels in serum of allergic and non-allergic children were largely similar, except for higher levels of C22:4 n-6 and C22:5 n-6 (p < 0.05 for both) and a higher AA:EPA ratio in serum phospholipids in the former group (p < 0.05). Changes in the levels of milk PUFA were reflected in changes in PUFA serum phospholipids, particularly for the n-6 PUFA. The AA: EPA ratio in maternal milk was related, however, to the AA:EPA only in serum from non-allergic children, while this was not the case in allergic children. The levels of total S-IgA, anti-cat S-IgA, anti-ovalbumin S-IgA, and anti-beta-lactoglobulin S-IgA in milk from mothers of allergic, as compared to non-allergic, children were similar through the first 3 months of lactation. Low levels of n-3 PUFA in human milk, and particularly a high AA:EPA ratio in maternal milk and serum phospholipids in the infants, were related to the development of symptoms of allergic disease at 18 months of age. The milk PUFA composition influenced the composition of PUFA in serum phospholipids of the children. We also showed that the lower levels of colostral anti-ovalbumin S-IgA and lower total S-IgA in mature milk from atopic mothers did not influence the development of allergic disease in the children up to 18 months of age. The findings indicate that low alpha-linolenic acid, C18:3 n-3 (LNA) and n-3 long-chain polyunsaturated fatty acids (LCP) 20-22 carbon chains, but not the levels of S-IgA antibodies to allergens, are related to the development of atopy in children.
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Affiliation(s)
- K Duchén
- Department of Health and Environment, Linköping University Hospital, Sweden.
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Innis SM. Essential fatty acids in infant nutrition: lessons and limitations from animal studies in relation to studies on infant fatty acid requirements. Am J Clin Nutr 2000; 71:238S-44S. [PMID: 10617978 DOI: 10.1093/ajcn/71.1.238s] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Animal studies have been of pivotal importance in advancing knowledge of the metabolism and roles of n-6 and n-3 fatty acids and the effects of specific dietary intakes on membrane composition and related functions. Advantages of animal studies include the rigid control of fatty acid and other nutrient intakes and the degree, timing, and duration of deficiency or excess, the absence of confounding environmental and clinical variables, and the tissue analysis and testing procedures that cannot be performed in human studies. However, differences among species in nutrient requirements and metabolism and the severity and duration of the dietary treatment must be considered before extrapolating results to humans. Studies in rodents and nonhuman primates fed diets severely deficient in alpha-linolenic acid (18:3n-3) showed altered visual function and behavioral problems, and played a fundamental role by identifying neural systems that may be sensitive to dietary n-3 fatty acid intakes; this information has assisted researchers in planning clinical studies. However, whereas animal studies have focused mainly on 18:3n-3 deficiency, there is considerable clinical interest in docosahexaenoic acid (22:6n-3) and arachidonic acid (20:4n-6) supplementation. Information from animal studies suggests that brain and retinal concentrations of 22:6n-3 plateau with 18:3n-3 intakes of approximately 0.7% of energy, but this requirement is influenced by dietary 18:2n-6 intake. Blood and tissue concentrations of 22:6n-3 increase as 22:6n-3 intake increases, with adverse effects on growth and function at high intakes. Animal studies can provide important information on the mechanisms of both beneficial and adverse effects and the pathways of brain 22:6n-3 uptake.
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MESH Headings
- Adult
- Animals
- Animals, Newborn
- Arachidonic Acid/metabolism
- Dietary Fats/metabolism
- Docosahexaenoic Acids/metabolism
- Fatty Acids, Essential/deficiency
- Fatty Acids, Essential/metabolism
- Fatty Acids, Essential/physiology
- Fatty Acids, Omega-3/administration & dosage
- Fatty Acids, Omega-3/metabolism
- Fatty Acids, Omega-6
- Fatty Acids, Unsaturated/administration & dosage
- Fatty Acids, Unsaturated/metabolism
- Female
- Humans
- Infant
- Infant Nutritional Physiological Phenomena/physiology
- Milk, Human/metabolism
- Milk, Human/physiology
- Nutritional Requirements
- Swine
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Affiliation(s)
- S M Innis
- Department of Paediatrics, University of British Columbia, Vancouver, Canada.
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