Vitamin E intakes and sources in the United States

Racial Differences in Pain, Nutrition, and Oxidative Stress

Investigating the disproportionate rates of chronic pain and their related comorbidities between Black and non-Hispanic White (White) individuals is a growing area of interest, both in the healthcare community and in general society. Researchers have identified racial differences in chronic pain prevalence and severity, but still very little is known about the mechanisms underlying them. Current explanations for these differences have primarily focused on socioeconomic status and unequal healthcare between races as causal factors. Whereas these factors are informative, a racial gap still exists between Black and White individuals when these factors are controlled for. One potential cause of this racial gap in chronic pain is the differences in nutrition and dietary intake between groups. Certain foods play a key role in the inflammatory and oxidative stress pathways in the human body and could potentially influence the severity of the pain experience. Here, we review the previous literature on the surrounding topics and propose a potential mechanism to explain racial differences in the chronic pain population, based on established racial differences in diet and oxidative stress.

Vitamin E for the management of major depressive disorder: possible role of the anti-inflammatory and antioxidant systems

OBJECTIVES

Vitamin E has various functions in humans, including antioxidant, anti-inflammatory, anti-cancer, and anti-atherogenic actions, as well as direct effects on enzymatic activities and modulation of gene transcription. In addition to these functions, vitamin E is also important for the central nervous system, and its role in the prevention and/or treatment of some neurological diseases has been suggested. In particular, the role of vitamin E in the modulation of major depressive disorder (MDD) is an issue that has emerged in recent studies. Many factors have been implicated in the pathophysiology of this disorder, including inflammation, oxidative, and nitrosative stress.

METHODS

This narrative review discusses the involvement of inflammation, oxidative, and nitrosative stress in the pathophysiology of MDD and presents clinical and preclinical studies that correlate vitamin E with this psychiatric disorder.

RESULTS

We gathered evidence from clinical studies that demonstrated the relationship between low vitamin E status and MDD symptoms. Vitamin E has been reported to exert a beneficial influence on the oxidative and inflammatory status of individuals, factors that may account for the attenuation of depressive symptoms. Preclinical studies have reinforced the antidepressant-like response of vitamin E, and the mechanisms underlying its effect seem to be related to the modulation of oxidative stress and neuroinflammation.

CONCLUSION

We suggest that vitamin E has potential to be used as an adjuvant for the management of MDD, but more studies are clearly needed to ascertain the efficacy of vitamin E for alleviating depressive symptoms.

Environment-wide association study on childhood obesity in the U.S

BACKGROUND

Childhood obesity is a national public health issue with increasing prevalence. It has been linked to diet, lack of physical activity, and genetic susceptibility, with more recent evidence that it could also result from environmental factors. Studies linking it to environmental factors are limited, unsystematic, incomprehensive, and inconclusive.

OBJECTIVE

To conduct an environment-wide association study (EWAS) to comprehensively investigate all the environmental factors available in a nationally representative sample of children to determine factors associated with childhood obesity.

METHODS

We utilized the 1999-2016 National Health and Nutrition Examination Survey (NHANES) datasets and included all children/adolescents (6-17 years). Obesity was measured using body mass index and waist to height ratio. A multinomial and binary logistic regression were used adjusting for age, sex, race/ethnicity, creatinine, calorie intake, physical activity, screen time, limitation to physical activities, and socioeconomic status. We then controlled for multiple hypothesis testing and validated our findings on a different cohort of children.

RESULTS

We found that metals such as beryllium (OR: 3.305 CI: 1.460-7.479) and platinum (OR: 1.346 CI: 1.107-1.636); vitamins such as gamma-tocopherol (OR: 8.297 CI: 5.683-12.114) and delta-tocopherol (OR: 1.841 CI:1.476-2.297); heterocyclic aromatic amines such as 2-Amino-9H-pyrido (2,3-b) indole (OR: 1.323 CI: 1.083-1.617) and 2-Amino-3-methyl-9H-pyriodo(2,3-b)indole (OR: 2.799 CI: 1.442-5.433); polycyclic aromatic amines such as 9- fluorene (OR: 1.509 CI: 1.230-1.851) and 4-phenanthrene (OR: 2.828 CI: 1.632-4.899); and caffeine metabolites such as 1,3,7-trimethyluric acid (OR: 1.22 CI: 1.029-1.414) and 1,3,7-trimethylxanthine (OR: 1.258 CI: 1.075-1.473) were positively and significantly associated with childhood obesity.

CONCLUSION

Following the unique concept of EWAS, certain environmental factors were associated with childhood obesity. Further studies are required to confirm these associations while investigating their mechanisms of action.

Associations between follicular fluid high density lipoprotein particle components and embryo quality among in vitro fertilization patients

PURPOSE

Follicular redox balance is likely to be important for embryo quality during in vitro fertilization (IVF), and the anti-oxidative high desity lipoprotein (HDL) particle is the sole lipoprotein measured in follicular fluid (FF). Therefore, we investigated FF HDL particle components as predictors of embryo quality during IVF.

METHODS

Two research follicles collected from each participant were individually tracked, and 103 women having at least one developed embryo were included in the analysis. Concentrations of 15 non-cholesterol HDL particle components and 26 HDL-cholesterol (HDL-C) particle size subfractions were determined. Embryo quality was assessed for embryo cell number, embryo fragmentation, and embryo symmetry. Multivariable Poisson regression with a sandwich variance estimator was used to evaluate associations between HDL particle components and embryo quality, adjusted for covariates.

RESULTS

Higher γ-tocopherol concentration was associated with less embryo fragmentation (relative risk [RR] = 4.43; 95 % confidence interval [CI] 1.78, 11.06), and higher apolipoprotein A-1 concentration was associated with full embryo symmetry (RR = 3.92; 95 % CI 1.56, 9.90). Higher concentrations of HDL-C subfractions in the large and medium particle size ranges were associated with poorer embryo quality.

CONCLUSIONS

FF HDL lipophilic micronutrients and protein components, as well as HDL-C particle size, may be important predictors of embryo quality during IVF.

Vitamin E intake from natural sources and head and neck cancer risk: a pooled analysis in the International Head and Neck Cancer Epidemiology consortium

BACKGROUND

Evidence for the possible effect of vitamin E on head and neck cancers (HNCs) is limited.

METHODS

We used individual-level pooled data from 10 case-control studies (5959 cases and 12 248 controls) participating in the International Head and Neck Cancer Epidemiology (INHANCE) consortium to assess the association between vitamin E intake from natural sources and cancer of the oral cavity/pharynx and larynx. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression models applied to quintile categories of non-alcohol energy-adjusted vitamin E intake.

RESULTS

Intake of vitamin E was inversely related to oral/pharyngeal cancer (OR for the fifth vs the first quintile category=0.59, 95% CI: 0.49-0.71; P for trend <0.001) and to laryngeal cancer (OR=0.67, 95% CI: 0.54-0.83, P for trend <0.001). There was, however, appreciable heterogeneity of the estimated effect across studies for oral/pharyngeal cancer. Inverse associations were generally observed for the anatomical subsites of oral and pharyngeal cancer and within covariate strata for both sites.

CONCLUSION

Our findings suggest that greater vitamin E intake from foods may lower HNC risk, although we were not able to explain the heterogeneity observed across studies or rule out certain sources of bias.

UPLC method for the determination of vitamin E homologues and derivatives in vegetable oils, margarines and supplement capsules using pentafluorophenyl column

A sensitive and rapid reversed-phase ultra performance liquid chromatographic (UPLC) method for the simultaneous determination of tocopherols (α-, β-, γ-, δ-), tocotrienols (α-, β-, γ-, δ-), α-tocopherol acetate and α-tocopherol nicotinate is described. The separation was achieved using a Kinetex pentafluorophenyl (PFP) column (150 × 2.1mm, 2.6 µm) with both photodiode array (PDA) and fluorescence (FL) detectors that were connected in series. Column was thermostated at 42°C. Under a gradient system consisting of methanol and water at a constant flow rate of 0.38 mL min(-1), all the ten analytes were well separated in less than 9.5 min. The method was validated in terms of linearity, limits of detection and quantitation, precision and recoveries. Calibration curves of the ten compounds were well correlated (r(2)>0.999) within the range of 100 to 25,000 μg L(-1) for α-tocopherol acetate and α-tocopherol nicotinate, 10 to 25,000 μg L(-1) for α-tocotrienol and 5 to 25,000 μg L(-1) for the other components. The method is simple and sensitive with detection limits (S/N, 3) of 1.0 to 3.0 μg L(-1) (FL detection) and 30 to 74 μg L(-1) (PDA detection). Relative standard deviations for intra- and inter-day retention times (<1%) and peak areas (≤ 4%) were obtained. The method was successfully applied to the determination of vitamin E in vegetable oils (extra virgin olive, virgin olive, pomace olive, blended virgin and refined olive, sunflower, soybean, palm olein, carotino, crude palm, walnut, rice bran and grape seed), margarines and supplements.

Chamaerops humilis L. var. argentea André date palm seed oil: a potential dietetic plant product

Chamaerops humilis L. var. argentea André (C. humilis) date palm seeds are an underutilized source of vegetable oil, and no studies describing their physicochemical characteristics to indicate the potential uses of this seed or seed oil have been reported. The oil content of the seeds is about 10%, mainly composed of oleic acid (38.71%), lauric acid (21.27%), linoleic acid (15.15%), palmitic acid (9.96%), and stearic acid (7.17%). The tocol (tocopherols and tocotrienols) content is 74 mg/100 g, with δ-tocotrienol as the major contributor (31.91%), followed by α-tocotrienol (29.37%), γ-tocopherol (20.16%), and γ-tocotrienol (11.86%). Furthermore, this oil shows high thermal stability. The differential scanning calorimetery curves revealed that the melting and crystallization points are 9.33 °C and -15.23 °C, respectively.

Evidence for a role of proteins, lipids, and phytochemicals in the prevention of polycystic kidney disease progression and severity

Polycystic kidney disease (PKD) is a heritable disease characterized by renal cysts and is a leading cause of end-stage renal disease. Dietary intervention offers a potentially efficacious, cost-effective, and safe therapeutic option for PKD. The aim of this article was to review studies investigating the effect of dietary components on PKD and potential mechanisms of action. Low-protein diets are commonly recommended for PKD patients, but inconsistent findings in human and animal PKD studies suggest that the type rather the amount of protein may be of greater importance. Dietary soy protein has been shown to have renal protective effects in various animal models of PKD. Other than dietary proteins, studies investigating the role of the amount and type of dietary lipids on PKD progression are increasing. The omega-3 polyunsaturated fatty acids can alter multiple steps in PKD pathogenesis. Phytoestrogens and phytochemicals are other dietary compounds shown to attenuate cyst pathogenesis in animal studies. A better understanding of the role of nutrition in PKD can contribute to the development of dietary recommendations and diet-based therapies to reduce PKD progression and severity.

Bioavailability of vitamin E in humans: an update

Vitamin E is essential for human health and may play a role in the prevention of some degenerative diseases. Its bioavailability, however, is wide ranging and is affected by numerous factors. Recent findings showing that the intestinal absorption of vitamin E involves proteins have raised new relevant questions about factors that can affect bioavailability. It is, therefore, opportune to present a current overview of this topic. This review begins by exploring what is known, as well as what is unknown, about the metabolization of vitamin E in the human upper gastrointestinal tract and then presents a methodical evaluation of factors assumed to affect vitamin E bioavailability. Three main conclusions can be drawn. First, the proteins ABCA1, NPC1L1, and SR-BI are implicated in the absorption of vitamin E. Second, the efficiency of vitamin E absorption is widely variable, though not accurately known (i.e., between 10% and 79%), and is affected by several dietary factors (e.g., food matrix, fat, and fat-soluble micronutrients). Finally, numerous unanswered questions remain about the metabolization of vitamin E in the intestinal lumen and about the factors affecting the efficiency of vitamin E absorption.

Quantitation of [5-14CH3]-(2R, 4'R, 8'R)-α-tocopherol in humans

Half-lives of α-tocopherol in plasma have been reported as 2-3 d, whereas the Elgin Study required >2 y to deplete α-tocopherol, so gaps exist in our quantitative understanding of human α-tocopherol metabolism. Therefore, 6 men and 6 women aged 27 ± 6 y (mean ± SD) ingested 1.81 nmol, 3.70 kBq of [5-(14)CH(3)]-(2R, 4'R, 8'R)-α-tocopherol. The levels of (14)C in blood plasma and washed RBC were monitored frequently from 0 to 460 d while the levels of (14)C in urine and feces were monitored from 0 to 21 d. Total fecal elimination (fecal + metabolic fecal) was 23.24 ± 5.81% of the (14)C dose, so feces over urine was the major route of elimination of the ingested [5-(14)CH(3)]-(2R, 4'R, 8'R)-α-tocopherol, consistent with prior estimates. The half-life of α-tocopherol varied in plasma and RBC according to the duration of study. The minute dose coupled with frequent monitoring over 460 d and 21 d for blood, urine, and feces ensured the [5-(14)CH(3)]-(2R, 4'R, 8'R)-α-tocopherol (the tracer) had the chance to fully mix with the endogenous [5-(14)CH(3)]-(2R, 4'R, 8'R)-α-tocopherol (the tracee). The (14)C levels in neither plasma nor RBC had returned to baseline by d 460, indicating that the t(1/2) of [5-CH(3)]-(2R, 4'R, 8'R)-α-tocopherol in human blood was longer than prior estimates.

Food composition database harmonization for between-country comparisons of nutrient data in the TEDDY Study

The Environmental Determinants of Diabetes in the Young Study (TEDDY) aims at examining the associations between islet autoimmunity and various environmental exposures, (e.g. diet) in Finland, Germany, Sweden and the United States (US). In order to produce comparable results from dietary assessments, the national food composition databases (FCDB) must contain mutually comparable food composition data. Systematic comparison (definition, unit of measurement, and method of analysis) of energy, protein, fats, carbohydrates, cholesterol, fiber, 13 vitamins, and 8 minerals was carried out among the FCDB of the four countries. Total fat, cholesterol, vitamin A: retinol equivalents and beta-carotene, thiamin, riboflavin, pyridoxine, vitamin B(12), calcium, phosphorus, potassium, magnesium, iron, and zinc are comparable across all four databases. Carbohydrates, fiber, sugars, fatty acids, vitamin D, vitamin E: alpha-tocopherol, vitamin K, vitamin C, pantothenic acid, niacin, manganese, and copper are comparable or can be converted comparable at least across three of the databases. Vitamin E: alpha-tocopherol equivalents, will be comparable across all databases after Finland and Germany subtract tocotrienols from their values. Nitrogen values were added to the Swedish and US databases. After recalculation of protein from nitrogen (Sweden and US), and subtraction of fiber from the total carbohydrate (Finland) followed by recalculations of energy, these values will be comparable across the countries. Starch and folate are not comparable.

Impact of vitamin E on immune function and its clinical implications

Vitamin E is a chain-breaking antioxidant that protects membranes from free-radical damage. Evidence suggests significant impact of vitamin E on the modulation of immune functions. Results from animal and human studies indicate that vitamin E deficiency impairs both humoral and cell-mediated immune functions. Supplementation of vitamin E above the recommended levels has been shown to enhance immune functions and to be associated with increased resistance against several pathogens, especially in the aged. The current vitamin E consumption status from diets, the status of vitamin E supplement use, the effects of vitamin E on different aspects of immune functions and mechanisms of its action and the clinical significance of vitamin E supplementation will be reviewed.

Inflammatory Disease Processes and Interactions with Nutrition

Inflammation is a stereotypical physiological response to infections and tissue injury; it initiates pathogen killing as well as tissue repair processes and helps to restore homeostasis at infected or damaged sites. Acute inflammatory reactions are usually self-limiting and resolve rapidly, due to the involvement of negative feedback mechanisms. Thus, regulated inflammatory responses are essential to remain healthy and maintain homeostasis. However, inflammatory responses that fail to regulate themselves can become chronic and contribute to the perpetuation and progression of disease. Characteristics typical of chronic inflammatory responses underlying the pathophysiology of several disorders include loss of barrier function, responsiveness to a normally benign stimulus, infiltration of inflammatory cells into compartments where they are not normally found in such high numbers, and overproduction of oxidants, cytokines, chemokines, eicosanoids and matrix metalloproteinases. The levels of these mediators amplify the inflammatory response, are destructive and contribute to the clinical symptoms. Various dietary components including long chain ω-3 fatty acids, antioxidant vitamins, plant flavonoids, prebiotics and probiotics have the potential to modulate predisposition to chronic inflammatory conditions and may have a role in their therapy. These components act through a variety of mechanisms including decreasing inflammatory mediator production through effects on cell signaling and gene expression (ω-3 fatty acids, vitamin E, plant flavonoids), reducing the production of damaging oxidants (vitamin E and other antioxidants), and promoting gut barrier function and anti-inflammatory responses (prebiotics and probiotics). However, in general really strong evidence of benefit to human health through anti-inflammatory actions is lacking for most of these dietary components. Thus, further studies addressing efficacy in humans linked to studies providing greater understanding of the mechanisms of action involved are required.

Sources of food group intakes among the US population, 2001-2002

BACKGROUND

Food guides are typically built around a system of food groups. Accordingly, the US Department of Agriculture's MyPyramid includes both food groups and subgroups, as well as an allowance for discretionary calories, in its guidance.

OBJECTIVE

To identify the major dietary contributors to food group intake in the US population.

METHODS

This cross-sectional study used 2001-2002 National Health and Nutrition Examination Survey data to determine weighted population proportions for the contribution of each subgroup to its MyPyramid food group (ie, proportion), and the contribution of specific foods to the subgroups oils, solid fats, and added sugars (ie, major contributors). Food codes associated with each food were sorted into 96 categories, termed specific foods, and were linked to the MyPyramid Equivalents Database to obtain food group equivalents.

RESULTS

In regard to proportion, dark green vegetables (6%), orange vegetables (5%), and legumes (6%) fell well short of recommended levels. Intake of whole grains (10% of total) was far below the recommendation that at least half of all grains be whole. In regard to major contributors, top sources of oils were potato chips, salad dressing, and nuts/seeds; major contributors of solid fats were grain-based desserts, cheese, and sausages. Sweetened carbonated beverages provided 37% of added sugars.

CONCLUSIONS

Americans do not, in general, consume the most nutrient-dense forms of basic food groups, instead consuming foods that are high in solid fats and added sugars. The main culprits-the foods that contribute most to discrepancies between recommendations and actual intake-are sweetened carbonated beverages and other sweetened beverages, grain-based desserts, nonskim dairy products, and fatty meats.

Adição da vitamina E aos alimentos: implicações para os alimentos e para a saúde humana

A ingestão de vitamina E em doses acima das estabelecidas pelas Dietary Reference Intake, na forma de alimentos ou suplementos, está relacionada à prevenção de doenças crônicas não transmissíveis, à estimulação do sistema imune e à modulação dos processos degenerativos relacionados ao envelhecimento. Por outro lado, a adição de vitamina E aos alimentos com o intuito de alcançar tais efeitos ainda não é comum, porque não há consenso sobre a dose a ser consumida. Em muitas populações tem sido necessário ingerir alimentos fortificados com vitamina E, para alcançar os níveis recomendados para a ingestão adequada. Este trabalho enfoca o papel da vitamina E como um componente antioxidante utilizado pela indústria alimentícia, como um composto que exerce funções específicas no organismo humano e no alimento e como um importante nutriente que, quando adicionado aos alimentos, é capaz de atuar contra a lipoperoxidação e contribuir para o aumento de sua ingestão, além de poder reduzir os efeitos deletérios dos processos oxidativos que ocorrem no organismo humano, prevenindo as doenças crônicas não transmissíveis.

Total alpha-tocopherol intakes are associated with serum alpha-tocopherol concentrations in African American adults

African Americans in the southern United States have a high prevalence of chronic disease. Tocopherol intake and status have been associated with protection against several chronic diseases. Our objectives were, therefore, to examine the association between tocopherol intakes as measured by 2 regional FFQ and their corresponding concentrations in serum and to report on dietary sources of tocopherols in 404 men and women participating in the cross-sectional Diet and Physical Activity Sub-Study of the Jackson Heart Study. A large proportion (49% of men and 66% of women) reported dietary supplement use. Only 5.8% of men and 4.5% of women met the estimated average requirement (EAR) for vitamin E from foods alone, whereas 44.2% men and 49.2% women met it from foods and supplements. Total (diet + supplement) intake of alpha-tocopherol was associated with its corresponding measure in serum. Vitamin E supplement use, sex, serum cholesterol, education, and BMI, but not gamma-tocopherol intakes, were associated with serum gamma-tocopherol. For delta-tocopherol, associated variables included sex and serum cholesterol. The top food sources of alpha- and gamma-tocopherol were snack chips and the top food source of delta-tocopherol was margarine. Despite prevalent vitamin E supplement use, more than one-half of this population did not meet the EAR for alpha-tocopherol intake and very few met it from food alone. Supplement use was associated with higher alpha- but lower gamma-tocopherol concentration in serum. The possible health implications of this difference in relative tocopherol subtypes require further study.

Vitamin E content of foods: Comparison of results obtained from food composition tables and HPLC analysis

BACKGROUND & AIMS

Data on vitamin E content of foods are essential for nutrition research and its application. The aim of this study was to investigate the precision of calculated vitamin E content of prepared meals.

METHODS

The vitamin E content of 69 dishes of a menu cycle sampled at two occasions were calculated using 4 different food composition tables (FCT) and measured by HPLC.

RESULTS

Data were complete for 50-69 dishes. The proportion of dishes with differences between FCTs < or = 20% were 17-100%. Differences between HPLC and the Souci-Fachmann-Kraut table were < or = 20% in 8/46 dishes for alpha- and in 14/46 dishes for gamma-tocopherol. Differences fell in the order of baked > raw > fried/roasted > boiled > mixed prepared foods. The 2 samplings taken 6 months apart showed considerable differences.

CONCLUSIONS

There are substantial differences in calculated/measured vitamin E content of prepared foods: (i) between different FCTs; (ii) between FCTs and HPLC, and (iii) between different seasons. This can be explained by intrinsic variability (breeding, season, country of origin, ripeness, freshness) and food processing, as well as selection of FCTs and should be taken into account when interpreting data of dietary intervention studies.

Bioaccessibility of carotenoids and vitamin E from their main dietary sources

Vitamin E and carotenoids are fat-soluble microconstituents that may exert beneficial effects in humans, including protection against cancer, cardiovascular diseases, and age-related eye diseases. Their bioavailability is influenced by various factors including food matrix, formulation, and food processing. Since human studies are labor-intensive, time-consuming, and expensive, the in vitro model used in this study is increasingly being used to estimate bioaccessibility of these microconstituents. However, the ability of this model to predict bioavailability in a healthy human population has not yet been verified. The first aim of this study was to validate this model by comparing model-derived bioaccessibility data with (i) human-derived bioaccessibility data and (ii) published mean bioavailability data reported in studies involving healthy humans. The second aim was to use it to measure alpha- and gamma-tocopherol, beta-carotene, lycopene, and lutein bioaccessibility from their main dietary sources. Bioaccessibility as assessed with the in vitro model was well correlated with human-derived bioaccessibility values (r = 0.90, p < 0.05), as well as relative mean bioavailability values reported in healthy human groups (r = 0.98, p < 0.001). The bioaccessibility of carotenoids and vitamin E from the main dietary sources was highly variable, ranging from less than 0.1% (beta-carotene from raw tomato) to almost 100% (alpha-tocopherol from white bread). Bioaccessibility was dependent on (i) microconstituent species (lutein > beta-carotene and alpha-carotene > lycopene and alpha-tocopherol generally > gamma-tocopherol), (ii) food matrix, and (iii) food processing.

The maximal amount of dietary alpha-tocopherol intake in U.S. adults (NHANES 2001-2002)

The current study was designed to determine the maximal amount of alpha-tocopherol intake obtained from food in the U.S. diet, and to examine the effect of different food group intakes on this amount. Data from 2138 men and 2213 women aged >18 y were obtained from the National Health and Nutrition Examination Survey (NHANES) 2001-2002. Linear programming was used to generate diets with maximal alpha-tocopherol intake, with the conditions of meeting the recommended daily allowances or adequate intakes for a set of nutrients, sodium and fat recommendations, and energy limits, and that were compatible with the observed dietary patterns in the population. With food use and energy constraints in models, diets formulated by linear programming provided 19.3-24.9 mg alpha-tocopherol for men and women aged 19-50 or >50 y. These amounts decreased to 15.4-19.9 mg with the addition of the sodium, dietary reference intake, and fat constraints. The relations between maximal alpha-tocopherol intake and food group intakes were influenced by total fat restrictions. Although meeting current recommendations (15 mg/d) appears feasible for individuals, dramatic dietary changes that include greater intakes of nuts and seeds, and fruit and vegetables, are needed. Careful selection of the highest vitamin E source foods within these groups could further increase the likelihood of meeting the current recommended daily allowance.

Sources of Energy and Nutrients in the Diets of Infants and Toddlers

OBJECTIVE

To identify major sources of energy and 24 nutrients and dietary constituents in the diets of US infants and toddlers and to describe shifts in major nutrient sources as children age.

DESIGN

Data from 24-hour recalls collected in the 2002 Feeding Infants and Toddlers Study were analyzed to determine the percentage contribution of foods and supplements to total intakes of energy, nutrients, and other dietary constituents. A total of 3,586 unique foods and dietary supplements were reported. Reported foods and supplements were classified into 71 groups based on similarities in nutrient content and use. Nine-hundred seventy-nine food mixtures were disaggregated into their ingredients and ingredients were classified into one of the 71 groups using the same decision rules that guided classification of foods analyzed at the whole food level.

SUBJECTS/SETTING

A national random sample of 3,022 US infants and toddlers 4 to 24 months of age.

STATISTICAL ANALYSES PERFORMED

The population proportion formula was used to determine the percentage contribution of each of the 71 groups to total intakes. This was done by summing the weighted amount of a given nutrient provided by a given group for all individuals in the sample and dividing by the total weighted amount of that nutrient consumed by all individuals from all foods and supplements. Groups that provided at least 1% of the nutrient in question were rank-ordered. Separate tabulations were prepared for three age groups (4-5 months, 6-11 months, and 12-24 months).

RESULTS

Infant formula, breast milk, and milk are major contributors of energy and most nutrients in the diets of infants and toddlers. Among toddlers, juices and fruit-flavored drinks are the second and third most important sources of energy. Fortified foods make substantial contributions to intakes of many essential nutrients, and these contributions increase as children age. For example, among toddlers, fortified grain-based foods make substantial contributions to intakes of vitamin A, iron, and folate, relative to foods that are naturally rich in these nutrients. Supplements also make substantial contributions to intakes of vitamins and selected minerals, particularly among toddlers.

CONCLUSIONS

In assessing dietary intakes of infants and toddlers, dietetics professionals need to carefully consider contributions of fortified foods and supplements. Dietetics professionals should educate caregivers of infants and toddlers about the importance of foods (rather than just nutrients) in promoting health and about the importance of early feeding practices in the development of lifelong eating habits. Caregivers should be encouraged to avoid relying on fortified foods and supplements to meet nutrient needs and educated about the potential risk of excessive intakes. Caregivers of toddlers and infants over 4 to 6 months of age who are consuming solid foods should be encouraged to feed a wide variety of fruits, vegetables, and whole grains, as well as foods naturally rich in iron.

Nutrient Inadequacy in Obese and Non-Obese Youth

Purpose: In this study, the Dietary Reference Intake standards were used to evaluate the prevalence of inadequate intakes of micronutrients in obese and non-obese youth.

Methods: Dietary intake was analyzed with a dietary history taken by a registered dietitian. The obese group (n=156) had a body mass index (BMI) above the 95th percentile for age and sex. The non-obese group (n=90) was between the tenth and 85th BMI percentiles.

Results: In the obese subjects, the prevalence of inadequate intakes was 81% for vitamin E and 27% for magnesium; the proportions with intakes below the Adequate Intakes (AIs) for calcium and vitamin D were 55% and 46%, respectively. The obese children consumed 124% of estimated need for energy, 32% of which came from fat. The non-obese had a similar prevalence of inadequate intakes (vitamin E, 93%; magnesium, 29%; calcium, 51%; vitamin D, 44%). They consumed 107% of estimated need for energy, and 31% of energy came from fat. For both groups, all other nutrient intakes were adequate.

Conclusions: Even though children may consume an excess of energy, they may not be meeting all of their micronutrient needs.

Complementary therapies for diabetes: the case for chromium, magnesium, and antioxidants

A growing body of interest on the possible beneficial role of chromium, magnesium, and antioxidant supplements in the treatment of diabetes has contributed to debate about their value for reaching metabolic control and to prevent chronic complications in diabetic subjects. In this article we use a systematic approach focused on clinically based evidence from clinical trials regarding the benefits of chromium, magnesium, and antioxidant supplements as complementary therapies in type 2 diabetes. Chromium, magnesium, and antioxidants are essential elements involved in the action of insulin and energetic metabolism, without serious adverse effects. However, at present there is insufficient clinically based evidence and its routine use in the treatment of type 2 diabetes is still controversial. Because the most frequent origin of deficiencies in micronutrients is an inadequate diet, health care providers should invest more effort on nutrition counseling rather than focusing on micronutrient supplementation in order to reach metabolic control of their patients. Results from long-term trials are needed in order to assess the safety and beneficial role of chromium, magnesium, and antioxidant supplements as complementary therapies in the management of type 2 diabetes.

Vitamin E and immune response in the aged: molecular mechanisms and clinical implications

Nutritional status has been indicated as a contributing factor to age-related dysregulation of the immune response. Vitamin E, a lipid-soluble antioxidant vitamin, is important for normal function of the immune cells. The elderly are at a greater risk for vitamin E intake that is lower than recommended levels. Vitamin E supplementation above currently recommended levels has been shown to improve immune functions in the aged including delayed-type hypersensitivity skin response and antibody production in response to vaccination, which was shown to be mediated through increased production of interleukin (IL)-2, leading to enhanced proliferation of T cells, and through reduced production of prostaglandin E(2), a T-cell suppressive factor, as a result of a decreased peroxynitrite formation. Vitamin E increased both cell-dividing and IL-producing capacities of naive T cells, but not memory T cells. The vitamin E-induced enhancement of immune functions in the aged was associated with significant improvement in resistance to influenza infection in aged mice and a reduced risk of acquiring upper respiratory infections in nursing home residents. Further studies are needed to determine the signaling mechanisms involved in the upregulation of naive T-cell function by vitamin E as well as the specific mechanisms involved in reduction of risk for upper respiratory infections.

Gamma-tocopherol--an underestimated vitamin?

The main research activities of the last decades on tocopherols were mainly focused on alpha-tocopherol, in particular when considering the biological activities. However, recent studies have increased the knowledge on gamma-tocopherol, which is the major form of vitamin E in the diet in the USA, but not in Europe. gamma-Tocopherol provides different antioxidant activities in food and in-vitro studies and showed higher activity in trapping lipophilic electrophiles and reactive nitrogen and oxygen species. The lower plasma levels of gamma- compared to alpha-tocopherol might be discussed in the light of different bioavailability, but also in a potential transformation from gamma- into alpha-tocopherol. From the metabolism end product, only that of gamma-tocopherol (2,7,8-trimethyl-2-(beta-carboxyethyl)-6-hydroxychroman), but not that of alpha-tocopherol, was identified to provide natriuretic activity. Studies also indicate that only the gamma-tocopherol plasma level served as biomarker for cancer and cardiovascular risk. Therefore, this paper provides a comprehensive review on gamma-tocopherol with emphasis on its chemistry, biosynthesis, occurrence in food, different intake linking to different plasma levels in USA and Europe, absorption and metabolism, biological activities, and possible role in human health.

Intake of alpha-tocopherol is limited among US adults

OBJECTIVE

To examine alpha-tocopherol intake and food sources of alpha-tocopherol in the US population relative to current Dietary Reference Intakes for vitamin E.

DESIGN

We analyzed food source and intake data from the 1994 to 1996 Continuing Survey of Food Intakes by Individuals (CSFII) with added values for alpha-tocopherol from the US Department of Agriculture National Nutrient Database for Standard Reference Release 15.

SUBJECTS

Data from 5,056 men and 4,703 women aged 20 years and older were obtained from the 1994 to 1996 CSFII.

STATISTICAL ANALYSES PERFORMED

The complex design and sampling weights of the CSFII survey were taken into account to calculate the mean alpha-tocopherol intake from diet, the SEM, and the percent of the Estimated Average Requirements (EARs) for alpha-tocopherol intake by age group and region.

RESULTS

Only 8.0% of men and 2.4% of women in the United States met the new EARs for vitamin E intake from foods alone. Regionally, only 5.8% of men and 2.1% of women in the South met these EARs, relative to 9.0% and 2.6%, respectively, in the Northeast. Top contributors of alpha-tocopherol for men and women included ready-to-eat cereal, sweet baked products, white bread, beef, oils, and salad dressing.

APPLICATIONS/CONCLUSIONS

The majority of men and women in the United States fail to meet the current recommendations for vitamin E intake. Many of the top contributors are not particularly high sources of alpha-tocopherol but are consumed frequently. Greater inclusion of sources such as nuts, seeds, and vitamin E-rich oils, could improve intake of alpha-tocopherol.

Biologic and methodologic issues for nutritional biomarkers

Nutritional biomarkers are used for a variety of purposes in large-scale population surveys and epidemiologic studies as well as smaller clinical studies. The main reasons for using nutritional biomarkers are to provide measures of nutritional status that have less error than dietary data, nutrient status for nutrients with inadequate dietary data, to obtain a more proximal and integrated assessment of nutrient status that incorporates metabolism, to assess dietary change and compliance in intervention studies, and dietary intake for the validation of dietary questionnaires. However, often there is oversight by the investigators regarding biologic and laboratory issues, which have implications for the utility of nutritional biomarkers. This article reviews some of the physiologic issues that contribute to between-person variability in nutrient status and the utility and meaning of specimens from various body compartments. Issues related to the collection and storage of biologic specimens are addressed, although it is recommended that investigators contact laboratory colleagues at the beginning of any study for updated information. The necessity for blind quality surveillance of laboratory analyses beyond the normal procedures employed by collaborating laboratories also is addressed. The advantages and disadvantages of nutritional biomarkers are reviewed, especially in comparison with using dietary methodology.

Dietary intake, dietary patterns, and changes with age: an epidemiological perspective

Cohort and cross-sectional data were reviewed to describe the changes in dietary intake with age. Total energy intake decreases varied substantially with age, by 1000 to 1200 kcal in men and by 600 to 800 kcal in women. This resulted in concomitant declines in most nutrient intakes. For some nutrients, substantial numbers of older Americans consumed only one fifth to one third of the recommended dietary allowance. For most nutrients, research is lacking with which to judge the health impact of reduced nutrient consumption with age, although there is some evidence of an age-related decline in absorptive and metabolic function. With the aging of the population, more research is needed on nutrient requirements and health outcomes, and public health efforts are needed to increase physical activity and food intake among older people.

Vitamin C status and mortality in US adults

BACKGROUND

Low vitamin C status may increase the risk of mortality from cancer and cardiovascular disease.

OBJECTIVE

The objective was to test whether an association existed between serum ascorbate concentrations and mortality and whether the association was modified by cigarette smoking status or sex.

DESIGN

Serum ascorbate concentrations were measured in adults as part of the second National Health and Nutrition Examination Survey (1976-1980). Vital status was ascertained 12-16 y later.

RESULTS

The relative risk (RR) of death, adjusted for potential confounders, was estimated by using Cox proportional hazards models. Men in the lowest (<28.4 micromol/L) compared with the highest (>/=73.8 micromol/L) serum ascorbate quartile had a 57% higher risk of dying from any cause (RR: 1.57; 95% CI: 1.21, 2.03) and a 62% higher risk of dying from cancer (RR: 1.62; 95% CI: 1.01, 2.59). In contrast, there was no increased risk among men in the middle 2 quartiles for these outcomes and no increased risk of cardiovascular disease mortality in any quartile. There was no association between serum ascorbate quartile and mortality among women. These findings were consistent when analyses were limited to nonsmokers or further to adults who never smoked, suggesting that the observed relations were not due to cigarette smoking.

CONCLUSIONS

These data suggest that men with low serum ascorbate concentrations may have an increased risk of mortality, probably because of an increased risk of dying from cancer. In contrast, serum ascorbate concentrations were not related to mortality among women.

Effect of functional food ingredients: vitamin E modulation of cardiovascular diseases and immune status in the elderly

Increased accumulation of free radicals over time reduces the effectiveness of antioxidant defense mechanisms and heightens the vulnerability of older individuals to a variety of oxidative insults and associated pathologic conditions. Both nutritive and nonnutritive components of foods may slow declines in certain body functions. Ingestion of vitamin E, an antioxidant nutrient, in amounts above current recommendations may reduce the risk of cardiovascular disease, enhance immune status, and otherwise modulate important degenerative conditions associated with aging. Early adoption of proper dietary habits helps adults to maintain quality of life as they age. Increased intake of vitamin E through selection of foods with large amounts of that vitamin and daily consumption of 5-8 servings of fruit and vegetables may reduce risk for cardiovascular disease and improve immune function in later life.

Ascorbate is depleted by smoking and repleted by moderate supplementation: a study in male smokers and nonsmokers with matched dietary antioxidant intakes

BACKGROUND

Lack of reliable dietary data has hampered the ability to effectively distinguish between effects of smoking and diet on plasma antioxidant status. As confirmed by analyses of comprehensive food-frequency questionnaires, the total dietary intakes of fruit and vegetables and of dietary antioxidants were not significantly different between the study groups in the present study, thereby enabling isolation of the effect of smoking.

OBJECTIVE

Our objective was to investigate the effect of smoking on plasma antioxidant status by measuring ascorbic acid, alpha-tocopherol, gamma-tocopherol, beta-carotene, and lycopene, and subsequently, to test the effect of a 3-mo dietary supplementation with a moderate-dose vitamin cocktail.

DESIGN

In a double-blind, placebo-controlled design, the effect of a vitamin cocktail containing 272 mg vitamin C, 31 mg all-rac-alpha-tocopheryl acetate, and 400 microg folic acid on plasma antioxidants was determined in a population of smokers (n = 37) and nonsmokers (n = 38). The population was selected for a low intake of fruit and vegetables and recruited from the San Francisco Bay area.

RESULTS

Only ascorbic acid was significantly depleted by smoking per se (P < 0.01). After the 3-mo supplementation period, ascorbic acid was efficiently repleted in smokers (P < 0.001). Plasma alpha-tocopherol and the ratio of alpha- to gamma-tocopherol increased significantly in both supplemented groups (P < 0.05).

CONCLUSIONS

Our data suggest that previous reports of lower concentrations of plasma vitamin E and carotenoids in smokers than in nonsmokers may primarily have been caused by differences in dietary habits between study groups. Plasma ascorbic acid was depleted by smoking and repleted by moderate supplementation.

Comparison of energy and nutrient sources of elderly Hispanics and non-Hispanic whites in New Mexico

OBJECTIVE

Identification and comparison of frequently consumed foods and important food sources of energy, protein, total fat, vitamin A, vitamin C, vitamin E, vitamin B-6, folate, and calcium of elderly Hispanics and non-Hispanic whites.

DESIGN

Dietary intake data were collected using a modified Health Habits and History Questionnaire (a food frequency questionnaire) for 735 subjects who participated in the New Mexico Elder Health Survey.

SUBJECTS

The sample consisted of 330 Hispanics (176 men and 154 women) and 405 non-Hispanic whites (214 men and 191 women) between the ages of 65 and 96 years. Subjects were those with food frequency data among 883 participants who completed the clinical visit of the New Mexico Elder Health Survey.

RESULTS

Results show the top-ranked frequently consumed foods by gender and ethnicity and top-ranked food sources of energy and 8 nutrients. Regional foods were important sources of nutrients in the diets of both Hispanics and non-Hispanic whites, however, more so for the Hispanics. Chile sauces were notable sources of vitamin A, vitamin C, and folate among both groups. Both ethnic groups demonstrated selection of low-fat and skim milk and moderation in consumption of red meat.

APPLICATIONS

These data will be useful for designing nutrition education programs, for studying the relationship between diet and disease among elderly Hispanics and non-Hispanic whites, and for designing assessment instruments for the elderly and other ethnic populations.