PUFA and LC-PUFA intake during the first year of life: can dietary practice achieve a guideline diet?

Production of polyunsaturated fatty acids by Schizochytrium (Aurantiochytrium) spp

Diverse health benefits are associated with dietary consumption of omega-3 long-chain polyunsaturated fatty acids (ω-3 LC-PUFA), particularly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Traditionally, these fatty acids have been obtained from fish oil, but limited supply, variably quality, and an inability to sustainably increase production for a rapidly growing market, are driving the quest for alternative sources. DHA derived from certain marine protists (heterotrophic thraustochytrids) already has an established history of commercial production for high-value dietary use, but is too expensive for use in aquaculture feeds, a much larger potential market for ω-3 LC-PUFA. Sustainable expansion of aquaculture is prevented by its current dependence on wild-caught fish oil as the source of ω-3 LC-PUFA nutrients required in the diet of aquacultured animals. Although several thraustochytrids have been shown to produce DHA and EPA, there is a particular interest in Schizochytrium spp. (now Aurantiochytrium spp.), as some of the better producers. The need for larger scale production has resulted in development of many strategies for improving productivity and production economics of ω-3 PUFA in Schizochytrium spp. Developments in fermentation technology and metabolic engineering for enhancing LC-PUFA production in Schizochytrium spp. are reviewed.

Metabolic and Metabolomic Insights Regarding the Omega-3 PUFAs Intake in Type 1 Diabetes Mellitus

Type 1 diabetes mellitus (T1DM) is currently considered an autoimmune disease characterized by the destruction of pancreatic β-cells, insulin deficiency, and dysglycemia. Dietary factors, including omega-3 polyunsaturated fatty acids (ω-3 PUFAs), were reported to influence T1DM. Therefore, a better understanding of the potential role of ω-3 PUFAs in the development and progression of T1DM will help to improve the clinical management of the disease. In this review, we explored the current understanding of molecular mechanisms and signaling pathways induced by ω-3 PUFAs and the beneficial effects of ω-3 PUFAs intake in the prevention and treatment of T1DM, as well as the underlying possible metabolomic (lipidomics) changes.

Biomarkers of Docosahexaenoic Acid but Not Arachidonic Acid Reflect Dietary Intakes in Toddlers at Ages 1 and 2 Years Who Are Not Meeting Dietary Recommendations

BACKGROUND

Long-chain n-6 and n-3 PUFAs are important for growth and development. However, little is known about requirements and current dietary intakes of these fatty acids in toddlers.

OBJECTIVES

This study assessed dietary intakes of n-6 and n-3 PUFAs and determined the relation to circulating PUFAs in toddlers at ages 1 and 2 y.

METHODS

This is a secondary analysis of data from toddlers enrolled in a double-blind randomized controlled trial of arachidonic acid (ARA) and DHA supplementation between ages 1 and 2 y. Dietary intakes of fatty acids were estimated by 3-d food records, and fatty acid composition in plasma total phospholipids, red blood cell phosphatidylethanolamine (PE), and phosphatidylcholine (PC) were assessed by GC at baseline in all subjects (n = 110; mean age 1.12 y; 64% male) and in the control subjects at 2 y (n = 43).

RESULTS

The dietary intakes of ARA, EPA, and DHA at age 1 y (baseline) were [mean (median)] 36.8 (30.0), 16.0 (0.00), and 31.1 (10.0) mg/d, respectively. Dietary intakes increased to 52.7 (45.0), 35.8 (0.00), and 64.8 (20.0) mg/d, respectively, at age 2 y (P < 0.05). The predominant dietary source of EPA and DHA was fish/seafood; eggs were an important source of ARA and DHA. Dietary DHA intakes were positively associated with plasma PE and PC DHA (P < 0.05). No relations between dietary ARA intakes and plasma PE and PC ARA (P > 0.05) were observed.

CONCLUSIONS

These findings suggest that most toddlers are not meeting the recommendation for dietary PUFA intakes and that higher dietary DHA intakes are reflected in plasma PE and PC DHA composition. Further work is required to investigate a biomarker for dietary ARA intake. This trial is registered at clinicaltrials.gov as NCT01263912.

Dietary Docosahexaenoic Acid and Arachidonic Acid in Early Life: What Is the Best Evidence for Policymakers?

BACKGROUND

A wealth of information on the functional roles of docosahexaenoic acid (DHA) and arachidonic acid (ARA) from cellular, animal, and human studies is available. Yet, there remains a lack of cohesion in policymaking for recommended dietary intakes of DHA and ARA in early life. This is predominantly driven by inconsistent findings from a relatively small number of randomised clinical trials (RCTs), which vary in design, methodology, and outcome measures, all of which were conducted in high-income countries. It is proposed that this selective evidence base may not fully represent the biological importance of DHA and ARA during early and later life and the aim of this paper is to consider a more inclusive and pragmatic approach to evidence assessment of DHA and ARA requirements in infants and young children, which will allow policymaking to reflect the marked diversity of need worldwide.

SUMMARY

Data from clinical RCTs is considered in the context of the extensive evidence from experimental, animal and human observational studies. Although the RCT data shows evidence of beneficial effects on visual function and in specific cognitive domains, early methodological approaches do not reflect current thinking and this undermines the strength of evidence. An outline of a framework for an inclusive and pragmatic approach to policy development on dietary DHA and ARA in early life is described.

CONCLUSION

High-quality RCTs that will determine long-term health outcomes in appropriate real-world settings need to be undertaken. In the meantime, a collective pragmatic approach to evidence assessment, may allow public health policymakers to make comprehensive reasoned judgements on the merits, costs, and expediency of dietary DHA and ARA interventions.

Scientific Opinion on the safety and suitability for use by infants of follow-on formulae with a protein content of at least 1.6 g/100 kcal

Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver a scientific opinion on the safety and suitability for use by infants of follow-on formulae (FOF) based on cow's milk intact protein with a protein content of at least 1.6 g/100 kcal (rounded value) that meet otherwise the requirements of relevant EU legislation. If the formula under evaluation is considered to be safe and suitable for use by infants, the NDA Panel is also asked to advise on whether FOF based on goat's milk intact protein, soy protein isolates or protein hydrolysates are also safe and suitable for infants under the same conditions. The Panel concludes that the use of FOF with a protein content of at least 1.6 g/100 kcal from either intact cow's milk protein or intact goat's milk protein otherwise complying with the requirements of relevant EU legislation is safe and suitable for healthy infants living in Europe with an intake of complementary foods of a sufficient quality. This conclusion does not apply to infant formula (IF). The Panel also concludes that the safety and suitability of FOF with a protein content of at least 1.6 g/100 kcal manufactured from either protein hydrolysates or soy protein isolates cannot be established with the available data. The same conclusion applies to IF. The NDA Panel endorsed a draft of this scientific opinion on 14 December 2016 for public consultation. The draft document has been revised and updated according to the comments received, where appropriate.

N. Dietary Intakes of Arachidonic Acid and Docosahexaenoic Acid in Early Life - With a Special Focus on Complementary Feeding in Developing Countries

BACKGROUND

In developing countries, dietary intakes of arachidonic acid (ARA) and docosahexaenoic acid (DHA) in early life are lower than current recommended levels. This review specifically focusses on the contribution that complementary feeding makes to ARA and DHA intakes in medium- to low-income countries. The aims of the review are (1) to determine the availability of ARA and DHA food sources in developing countries, (2) to estimate the contribution of complementary feeding to dietary intakes of ARA and DHA in infants aged 6-36 months, and (3) to relate the dietary ARA and DHA intake data to key socioeconomic and health indicators.

SUMMARY

The primary dietary data was collected by the Food and Agriculture Organisation (FAO) using Food Balance Sheets, and fatty acid composition was based on the Australian food composition tables. There is evidence of wide variation in per capita dietary intake for both DHA and ARA food sources, with low intakes of meat and seafood products being highly prevalent in most low-income countries. In children aged 6-36 months, the supply of ARA and DHA from the longer duration of breastfeeding in low-income countries is counterbalanced by the exceptionally low provision of ARA and DHA from complementary foods. The lowest tertile for ARA intake is associated with higher percentages of childhood stunting, birth rate, infant mortality, and longer duration of breast feeding. Key Message: In developing countries, intakes of DHA and ARA from complementary foods are low, and public health organisations need to adopt pragmatic strategies that will ensure that there is a nutritional safety net for the most vulnerable infants.

The importance of dietary DHA and ARA in early life: a public health perspective

Although the literature on the contribution of DHA and arachidonic acid (ARA) to fundamental metabolic functions in brain, immune and cardiovascular systems is extensive, there is a lack of consensus on the need for explicit recommendations on dietary intake for both DHA and ARA during the early years of life. This review takes a public health perspective with the objective of ensuring that recommendations protect the most vulnerable children worldwide. Most studies on the effects of DHA and ARA in early life have been undertaken in high-income countries and this is reflected in policy recommendations. Although breast milk is considered the gold standard and always contains DHA and ARA, there are proposals that infant formulas, especially follow-on formulas, do not need to be supplemented with these fatty acids. Complementary foods frequently have low concentrations of ARA and DHA and this is most significant in low-income countries where availability is also limited. Recent evidence shows that in developing countries, intakes of DHA and ARA during the age period 6–36 months are low and this relates to low national income. It is concluded that a continuum of DHA and ARA intake needs to be maintained during early life, a critical period of infant growth and development. For both infant and follow-on formulas, DHA and ARA should be mandatory at levels that are equivalent to breast milk. An optional recommendation may be limited to countries that can demonstrate evidence of adequate intakes of DHA and ARA during early life.

Systematic Review on N-3 and N-6 Polyunsaturated Fatty Acid Intake in European Countries in Light of the Current Recommendations - Focus on Specific Population Groups

BACKGROUND

Earlier reviews indicated that in many countries adults, children and adolescents consume on an average less polyunsaturated fatty acids (PUFAs) than recommended by the Food and Agriculture Organisation/World Health Organisation.

SUMMARY

The intake of total and individual n-3 and n-6 PUFAs in European infants, children, adolescents, elderly and pregnant/lactating women was evaluated systematically.

RESULTS

The evaluations were done against recommendations of the European Food Safety Authority. Key Messages: Fifty-three studies from 17 different European countries reported an intake of total n-3 and n-6 PUFAs and/or individual n-3 or n-6 PUFAs in at least one of the specific population groups: 10 in pregnant women, 4 in lactating women, 3 in infants 6-12 months, 6 in children 1-3 years, 11 in children 4-9 years, 8 in adolescents 10-18 years and 11 in elderly >65 years. Mean linoleic acid intake was within the recommendation (4 energy percentage [E%]) in 52% of the countries, with inadequate intakes more likely in lactating women, adolescents and elderly. Mean α-linolenic acid intake was within the recommendation (0.5 E%) in 77% of the countries. In 26% of the countries, mean eicosapentaenoic acid and/or docosahexaenoic acid intake was as recommended. These results indicate that intake of n-3 and n-6 PUFAs may be suboptimal in specific population groups in Europe.

Polyunsaturated fatty acid supplementation in infancy for the prevention of allergy

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.

The Essentiality of Arachidonic Acid in Infant Development

Arachidonic acid (ARA, 20:4n-6) is an n-6 polyunsaturated 20-carbon fatty acid formed by the biosynthesis from linoleic acid (LA, 18:2n-6). This review considers the essential role that ARA plays in infant development. ARA is always present in human milk at a relatively fixed level and is accumulated in tissues throughout the body where it serves several important functions. Without the provision of preformed ARA in human milk or infant formula the growing infant cannot maintain ARA levels from synthetic pathways alone that are sufficient to meet metabolic demand. During late infancy and early childhood the amount of dietary ARA provided by solid foods is low. ARA serves as a precursor to leukotrienes, prostaglandins, and thromboxanes, collectively known as eicosanoids which are important for immunity and immune response. There is strong evidence based on animal and human studies that ARA is critical for infant growth, brain development, and health. These studies also demonstrate the importance of balancing the amounts of ARA and DHA as too much DHA may suppress the benefits provided by ARA. Both ARA and DHA have been added to infant formulas and follow-on formulas for more than two decades. The amounts and ratios of ARA and DHA needed in infant formula are discussed based on an in depth review of the available scientific evidence.

Maternal PUFA ω-3 Supplementation Prevents Neonatal Lung Injuries Induced by Hyperoxia in Newborn Rats

Bronchopulmonary dysplasia (BPD) is one of the most common complications of prematurity, occurring in 30% of very low birth weight infants. The benefits of dietary intake of polyunsaturated fatty acids ω-3 (PUFA ω-3) during pregnancy or the perinatal period have been reported. The aim of this study was to assess the effects of maternal PUFA ω-3 supplementation on lung injuries in newborn rats exposed to prolonged hyperoxia. Pregnant female Wistar rats (n = 14) were fed a control diet (n = 2), a PUFA ω-6 diet (n = 6), or a PUFA ω-3 diet (n = 6), starting with the 14th gestation day. At Day 1, female and newborn rats (10 per female) were exposed to hyperoxia (O₂, n = 70) or to the ambient air (Air, n = 70). Six groups of newborns rats were obtained: PUFA ω-6/O₂ (n = 30), PUFA ω-6/air (n = 30), PUFA ω-3/O₂ (n = 30), PUFA ω-3/air (n = 30), control/O₂ (n = 10), and control/air (n = 10). After 10 days, lungs were removed for analysis of alveolarization and pulmonary vascular development. Survival rate was 100%. Hyperoxia reduced alveolarization and increased pulmonary vascular wall thickness in both control (n = 20) and PUFA ω-6 groups (n = 60). Maternal PUFA ω-3 supplementation prevented the decrease in alveolarization caused by hyperoxia (n = 30) compared to PUFA ω-6/O₂ (n = 30) or to the control/O₂ (n = 10), but did not significantly increase the thickness of the lung vascular wall. Therefore, maternal PUFA ω-3 supplementation may protect newborn rats from lung injuries induced by hyperoxia. In clinical settings, maternal PUFA ω-3 supplementation during pregnancy and during lactation may prevent BPD development after premature birth.

Fish and rapeseed oil consumption in infants and mothers: dietary habits and determinants in a nationwide sample in Germany

PURPOSE

Fish and rapeseed oil are major sources of omega-3 polyunsaturated fatty acids (n-3 PUFA) in complementary food, but little is known about current consumption in Germany.

METHODS

We conducted a nationwide consumer survey to assess the consumption habits of fish and rapeseed oil and their determining factors in 985 mother-child dyads in Germany.

RESULTS

One-fourth of infants ate fish as often as recommended, i.e. at least once per week. Half of the mothers stated that they mainly used rapeseed oil for self-prepared and/or commercial vegetable-potato-meat meals. In contrast, mothers more frequently met recommendations for fish consumption (41 %), but used rapeseed oil (34 %) less often for their own nutrition. Maternal eating behaviour was the most important predictor for both of these n-3 PUFA rich foods in infants' nutrition. In contrast to infants' fish consumption, rapeseed oil intake in infancy was found to be influenced by some further factors, i.e. mothers' social class and omega-3 knowledge, which were also key determinants of mothers' own fish and rapeseed oil consumption.

CONCLUSION

To promote fish with complementary feeding, programs should focus on families whose mothers rarely eat fish. Nutritional campaigns to improve omega-3 knowledge-especially focusing on lower social classes-could be effective in increasing rapeseed oil consumption, although these programs should be combined with environmental improvements as it has been already started through the use of rapeseed oil in commercial baby jars.

Complementary Feeding: Critical Considerations to Optimize Growth, Nutrition, and Feeding Behavior

This review focuses on complementary feeding (CF) in westernized settings where primary health concerns are risk of obesity and micronutrient inadequacy. The current evidence is reviewed for: (1) when CF should be introduced, (2) what foods (nutrients and food types) should be prioritized and avoided, and (3) how the infant should be fed. Special attention is paid to the underlying physiological differences between breast- and formula-fed infants that often result in distinctly different nutritional and health risks. This difference is particularly acute in the case of micronutrient inadequacy, specifically iron and zinc, but is also relevant to optimal energy and macronutrient intakes. Emphasis is placed on the complex interplay among infants' early dietary exposures; relatively high energy and nutrient requirements; rapid physical, social and emotional development; and the feeding environment-all of which interact to impact health outcomes. This complexity needs to be considered at both individual and population levels and in both clinical and research settings.

Science base of complementary feeding practice in infancy

PURPOSE OF REVIEW

The review presents a selection of publications on complementary feeding in industrialized countries during 2008-2009, after the publication of the ESPGHAN position paper in early 2008.

RECENT FINDINGS

The WHO recommendation for introduction of complementary feeding at 6 months is adapted in many countries, but the issue is still discussed and many mothers introduce complementary feeding as early as before 4 months. The European Food Safety Authority recently published a comprehensive review on the appropriate age for the introduction of complementary feeding and concluded that introduction between 4 and 6 months is safe. One study showed that delaying introduction of complementary feeding up to 6 months resulted in lower risk of overweight as adult. Milk protein is stimulating insulin-like growth factor-1 and growth and a recent study supports a long-term programming of the insulin-like growth factor-1 axis. There is now a broad consensus that there is no need to delay the introduction of hyperallergenic foods, which might even increase the risk of allergic disease. Randomized studies show that docosahexaenoic acid may affect heart rate and thereby cardiovascular regulation.

SUMMARY

Despite some recent interesting publications, there is still a need for more large randomized studies to further explore to what degree the time of introduction and composition of complementary foods have effects on growth, development and especially the long-term risk of diseases.