Ecological-level associations between highly processed food intakes and plasma phospholipid elaidic acid concentrations: results from a cross-sectional study within the European prospective investigation into cancer and nutrition (EPIC)

Elaidic acid is the main unnatural trans fatty acid isomer occurring during partial hydrogenation of vegetable oils used as ingredients for the formulation of processed foods. The main objective is to assess associations between processed food intakes and plasma phospholipid elaidic acid concentrations within the European Prospective Investigation into Cancer and Nutrition study. A cross-sectional study was used to determine fatty acid profiles in 3,003 subjects from 16 centers. Single 24-h dietary recalls (24-HDR) were collected using a standardized computerized interview program. Food intakes were computed according to their degree of processing (moderately/nonprocessed foods, processed staple foods, highly processed foods). Adjusted ecological and individual correlations were calculated between processed food intakes and plasma elaidic acid levels. At the population level, mean intakes of highly processed foods were strongly correlated with mean levels of plasma elaidic acid in men (P = 0.0016) and in women (P = 0.0012). At the individual level, these associations remained but at a much lower level in men (r = 0.08, P = 0.006) and in women (r = 0.09, P = 0.0001). The use of an averaged 24-HDR measure of highly processed food intakes is adequate for predicting mean levels of plasma elaidic acid among European populations.     

Is there a relationship between the food intakes of Scottish 5½−8½‐year‐olds and those of their mothers?

Background Recent reports have highlighted certain aspects of the diets of children and adults in Scotland today that are a cause for concern. If there are significant associations between family members in food choice and thus in nutrient intakes, this may be important in the aetiology and prevention of diseases relating to dietary risk factors. Aim To compare the food intake of Scottish children aged 5½?8½ years with that of their mothers. Methods As part of a larger study, data on food intakes were obtained from 4‐day weighed food records for 36 Scottish children (12 boys and 24 girls), aged 5½?8½ years, who had participated in the 1992/1993 National Diet and Nutrition Survey (NDNS), and their mothers. Results Compared with their mothers, children had higher median densities [weight (g) of foods per 4.2 MJ (1000 kcal)] of snack foods including fruit, bread and confectionery and lower median densities of meat and meat products, fish, potatoes and vegetables. Positive, significant correlations between children and mothers were found for median densities of bread (r = 0.360, P < 0.05), fruit (r = 0.735, P < 0.001) and potatoes (r = 0.572, P < 0.001) and also for chips (r = 0.651, P < 0.001) and chocolate confectionery (r = 0.368, P < 0.05), the latter two being foods that should be reduced in the average Scottish diet. Conclusions Children's intakes of snack foods were correlated with that of their mothers emphasizing the need for change at a family level if current guidelines on diet are to be implemented.     

Validation of a Short,Qualitative Food Frequency Questionnaire in French Adults Participating in the MONA LISA-NUT Study 2005-2007

BackgroundFood frequency questionnaires (FFQs) are often used to evaluate individuals' food intakes in epidemiologic studies because of their simplicity and low cost.ObjectiveTo assess the validity of a short (24 items), qualitative FFQ used in the MONA LISA-NUT study.DesignCross-sectional study of a representative sample in three French counties.Participants/settingThe sample included 2,630 participants aged 35 to 65 years from the MONA LISA-NUT study.Main outcome measuresFood consumption was measured with the FFQ and via food records for 3 consecutive days. Plasma fatty acids were measured from a subset of participants.Statistical analyses performedThe FFQ items' validity was assessed by calculating crude and deattenuated Pearson correlation coefficients between frequencies reported by the FFQ and average weights reported by the food records. Furthermore, the validity of some items of the FFQ measuring the consumption of fatty foods was assessed by calculating Pearson correlation coefficients between frequencies of consumption of these foods and dosages of the corresponding plasma fatty acids: fish and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), olive oil and oleic acid, margarine and elaidic acid, and dairy products and pentadecanoic and heptadecanoic acids.ResultsThe mean of the deattenuated Pearson correlation coefficients for all items was 0.46, with values ranging from 0.22 (fried food) to 0.77 (breakfast cereal). The correlation coefficient was ≤0.4 for one third of the 24 items. Moderate correlations were found between fish and EPA/DHA (EPA: r=0.43, 95% CI 0.33 to 0.51; DHA: r=0.39, 95% CI 0.30 to 0.47), but not for other food items.ConclusionsOne third of the 24 items in the short, qualitative FFQ evaluated here were not sufficiently valid. However, for the food groups most commonly studied in the literature, this FFQ had the same degree of validity as other questionnaires designed to classify subjects according to their level of intake.     

Estimated Intakes of Trans Fatty and Other Fatty Acids in the US Population

Objective To estimate mean level of trans fatty acid intakes using a representative sample of the US population.Design The study used food intake data from the 1989-1991 Continuing Survey of Food Intakes by Individuals (CSFII) and the trans fatty acid contents of specific foods calculated from a database compiled by the US Department of Agriculture (USDA) to estimate the mean level and deciles of trans fatty acid intake of the representative US population.Subjects/setting Trans fatty acid intakes were estimated for each subject (N=11,258) in the CSFII data who completed both a 24-hour recall and a 2-day food record.Statistical analyses performed Weights developed by USDA for the survey were used for all data analyses. The Technical Assessment Systems (TAS) International Diet Research System (TAS-DIET), software developed by TAS, was used to derive weighted estimates of the mean and percentiles of the intake distribution. PC CARP, software designed by Iowa State University, was used to estimate standard errors.Results Mean percentage of energy ingested as trans fatty acids was 2.6% and the mean percentage of total fat ingested as trans fatty acids was 7.4%. Across all age and gender groups examined, estimates ranged from 2.6% to 2.8% and 7.1% to 7.9%, respectively.Applications/conclusions Dietetics practitioners can use the representative data of this study to help clients achieve desired changes in consumption levels of trans fatty acids.J Am Diet Assoc. 1999;99:166–174.     

Validity and reproducibility of the food frequency questionnaire used in the Shanghai Women's Health Study

To evaluate the validity and reliability of the food frequency questionnaire (FFQ) used in the Shanghai Women's Health Study (SWHS), 200 SWHS participants were recruited for a dietary calibration study. Study participants completed an FFQ at baseline and 24-h dietary recalls (24-HDR) twice per month consecutively for 12 months. At the end of the study, a second FFQ was administered. Of the 200 study participants, 196 completed 24 or more days of 24-h dietary recalls, 191 completed two FFQs from whom the results of this report were based. The FFQ included the foods that accounted for 86% of the foods recorded in the 24-HDR surveys. Validity of the FFQ was evaluated by comparing intake levels of major nutrients and foods obtained from the second FFQ with those derived from the multiple 24-HDR. The median intake for major nutrients, rice, poultry and meat derived from the second FFQ and the 24-HDR was similar, with the differences ranging from 1.3 to 12.1%. The FFQ tended to overestimate the intake level of total vegetables and total fruits, and the differences were explained mainly by over-reporting seasonal vegetables and fruits consumption in the FFQ. Nutrient and food intake assessed by the FFQ and the multiple 24-HDR correlated very well, with the correlation coefficients being 0.59-0.66 for macronutrients, 0.41-0.59 for micronutrients, and 0.41-0.66 for major food groups. The reliability of the FFQ was assessed by comparing the correlation and median intake of nutrients and food groups obtained from the two FFQs that were administered approximately 2 y apart. The median intake levels for selected nutrients and food groups derived from the two FFQs were similar with differences below 10%. At the individual level, the intake levels of these dietary variables obtained from two FFQs also correlated well. When nutrient and food group intakes were categorized into quartiles, FFQ and 24-HDR produced exact agreement rates between 33 and 50%. Misclassification to adjacent quartile was common, ranging from 34-48%, while misclassification to an extreme quartile was rare (1-6%). These data indicate that the SWHS FFQ can reliably and accurately measure usual intake of major nutrients and food groups among women in Shanghai.     

Validity and reliability of a quantitative food frequency questionnaire measuring n-3 fatty acid intakes in cardiac patients in the Midwest: a validation pilot study

The purpose of this pilot study was to test the validity and reliability of a quantitative n-3 fatty acid food frequency questionnaire (FFQ) for later use with larger groups of individuals. A convenience sample of heart patients provided dietary data via three 24-hour food recalls and FFQs. Participants were women (n=17) and men (n=11), 43 to 77 years of age. The association of mean daily intake of n-3 fatty acids obtained using food recalls and the FFQ was assessed by Pearson correlation. The reliability of the FFQ was assessed using coefficient alpha. Correlation of n-3 fatty acid intake using the food recalls and the FFQ was r=0.42 (P<0.05). The coefficient alpha for the test-retest of the FFQ was .83. The top two foods, walnuts and flaxseed, contributed 58% of the n-3 fatty acid intake, and the third food, salmon, contributed 5%. This quantitative n-3 FFQ is a valid instrument for use in place of food recalls for estimating n-3 fatty acid intakes in heart patients and is a reliable instrument to estimate n-3 fatty acid intakes from plant, animal, and seafood sources. The FFQ should be tested in a larger population. Registered dietitians can use this FFQ to screen for intakes, educate patients on food sources, and measure change in intakes after nutrition intervention.     

Biomarker and dietary validation of a Canadian food frequency questionnaire to measure eicosapentaenoic and docosahexaenoic acid intakes from whole food, functional food, and nutraceutical sources

BackgroundCanadian dietary sources of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) include marine and non-marine whole foods, functional foods, and nutraceuticals.Objective/designIn the present study, these sources were incorporated into a nutrient-specific, semi-quantitative food frequency questionnaire (FFQ) and the ability to measure the EPA and DHA intakes of Canadian adults was assessed. Specifically, the EPA and DHA intakes estimated by FFQ of 78 men and women, 20 to 60 years of age, were compared with EPA and DHA measurements from 3-day food records and measures of EPA and DHA in fasting whole blood.ResultsMean (±standard deviation) and median intakes of EPA+DHA were 0.34±0.34 and 0.21 g/day by FFQ and 0.47±0.71 and 0.13 g/day by food record, with no significant differences between mean intakes (P=0.93). The FFQ provided higher estimates than the food record at low intakes of EPA and DHA and lower estimates at high intakes based on Bland-Altman plots. The FFQ was moderately correlated with food record (r=0.31 to 0.49) and with blood biomarker measures of EPA and DHA (r=0.31 to 0.51). Agreement analysis revealed that 42% of participants were classified in the same and 77% into same or adjacent quartile when EPA and DHA intake was assessed by food record and by FFQ. Similar quartile agreement was found for EPA and DHA intakes by FFQ with blood biomarker EPA and DHA. The range of the validity coefficients, calculated using the method of triads, was 0.43 to 0.71 for FFQ measurement of EPA+DHA.ConclusionsThe FFQ is an adequate tool for estimating usual EPA and DHA intakes and ranking Canadian adults by their intakes.     

The development and evaluation of a food frequency questionnaire used in assessing vitamin D intake in a sample of healthy young Canadian adults of diverse ancestry

Little data exist on vitamin D deficiency related with intake, especially for the Canadian population. The purpose of this study was to develop and evaluate a food frequency questionnaire (FFQ) with 37 items for rapid assessment of vitamin D intake in healthy young adults of diverse ancestry. We recruited 107 subjects in Southern Ontario during the late winter of 2007 who completed an FFQ twice (FFQ-1 and FFQ-2, repeated for reproducibility assessment) and a 7-day food diary (for validation). Serum 25-hydroxyvitamin D (25(OH)D), the major biomarker of vitamin D nutritional status, and skin melanin were determined. The FFQ results were highly correlated with 7-day diary results and with serum 25(OH)D concentrations (r = 0.529, P < .001; r = 0.481, P < .001, respectively). Modifications to the FFQ, by redefining the large serving size and excluding the fortified orange juice category, improved the validity of the FFQ (r = 0.602, P < .001; r = 0.520, P < .001, respectively). The FFQ results were highly correlated (r = 0.663, P < .001), but the mean intakes were different (P < .05). Using results from a modified version of FFQ-1, we examined dietary intakes in 3 predominant groups: East Asian (n = 27), European (n = 31), and South Asian (n = 32). The European group had higher total vitamin D intake (P < .05) and the highest serum 25(OH)D concentrations (P < .05), with a trend for dairy products being responsible for this (P < .10). Because Canadians are reliant on dietary intakes of vitamin D in the wintertime, especially those with higher skin melanin, our FFQ can monitor and provide information on intake and food group consumption.     

Food groups and fatty acids associated with self-reported depression: An analysis from the Australian National Nutrition and Health Surveys

ObjectiveThe aim of this study was to explore the associations between incidence of depression and dietary intakes of foods and fatty acids in adult Australians.MethodsData from the 1995 Australian National Nutrition Survey (NNS), the 1995 Australian National Health Survey (NHS) and an updated fatty acid database were merged and the 24-h fatty acid intakes were calculated for the 10 986 adult participants ages 18 to 79 y in the 1995 NNS. The merged data set was used to run a logistic regression with depression as the response variable and the food groups and calculated fatty acid values, age, and sex as predictors.ResultsThe regression model indicated that increased intakes per kilojoule of meat, poultry, and game; vegetables; and eicosapentaenoic acid (EPA) are associated with lower odds of having depression, whereas increased intakes of non-alcoholic beverages, milk products and dishes, and docosapentaenoic acid (DPA) are associated with an increase in the odds of having depression. The results confirm a collective effect of diet on mood. Although other studies have shown that fish consumption is associated with lower odds of depression, this study showed lower odds of depression with high meat consumption, possibly reflecting the fact that Australians consume six times more meat than fish.ConclusionSignificant associations between food and mood identified in this study warrant further research to determine causality.     

Can an iron-rich staple food help women to achieve dietary targets in pregnancy?

Habitual iron intakes during pregnancy are typically lower than dietary guidelines, a risk for iron deficiency. The aim of this study was to determine whether regular consumption of bread naturally rich in iron could help women to achieve dietary targets. Thirty-three primiparous mothers were randomized to eat 3–4 slices of iron-rich or control bread daily for 6 weeks. Two 24-h-prompted (multiple-pass) dietary recalls were completed, and validated algorithms were used to determine the amount of ‘available iron’ from the diet. Regular consumption of iron-rich bread helped pregnant women to achieve UK dietary recommendations; the quantity of bread consumed by the participants contributed 27% versus 9% UK Reference Nutrient Intake (RNI) (14.8 mg/d) in the intervention versus the control group. Levels of total ‘available iron’ were similar in both groups and correlated positively with total dietary iron (r = 0.78, P = 0.0001), vitamin C (r = 0.43, P = 0.017) and non-haem iron (r = 0.77, P = 0.0001). Findings from this study show that iron-rich staple foods can help women reach dietary targets for iron. This is an area of great potential that could be of particular benefit to low-income/ethnically diverse population groups who have some of the lowest iron intakes. Further research using fortified staple foods containing higher levels of iron is now warranted to establish physiological benefits.     

Dietary reporting errors on 24 h recalls and dietary questionnaires are associated with BMI across six European countries as evaluated with recovery biomarkers for protein and potassium intake

Whether there are differences between countries in the validity of self-reported diet in relation to BMI, as evaluated using recovery biomarkers, is not well understood. We aimed to evaluate BMI-related reporting errors on 24 h dietary recalls (24-HDR) and on dietary questionnaires (DQ) using biomarkers for protein and K intake and whether the BMI effect differs between six European countries. Between 1995 and 1999, 1086 men and women participating in the European Prospective Investigation into Cancer and Nutrition completed a single 24-HDR, a DQ and one 24 h urine collection. In regression analysis, controlling for age, sex, education and country, each unit (1 kg/m2) increase in BMI predicted an approximately 1·7 and 1·3 % increase in protein under-reporting on 24-HDR and DQ, respectively (both P < 0·0001). Exclusion of individuals who probably misreported energy intake attenuated BMI-related bias on both instruments. The BMI effect on protein under-reporting did not differ for men and women and neither between countries on both instruments as tested by interaction (all P>0·15). In women, but not in men, the DQ yielded higher mean intakes of protein that were closer to the biomarker-based measurements across BMI groups when compared with 24-HDR. Results for K were similar to those of protein, although BMI-related under-reporting of K was of a smaller magnitude, suggesting differential misreporting of foods. Under-reporting of protein and K appears to be predicted by BMI, but this effect may be driven by 'low-energy reporters'. The BMI effect on under-reporting seems to be the same across countries.     

Processed and Packed: How Refined Are the Foods That Children Bring to School for Snack and Lunch?

BackgroundIncreasing consumption of highly processed foods has been associated with adverse health outcomes among children. In the US, children consume up to half of their daily energy intake at school.ObjectivesWe sought to characterize foods that children bring from home to school according to processing level and to evaluate the effectiveness of a school-based intervention, Great Taste Less Waste (GTLW), in reducing the proportion of energy brought from highly processed foods from home compared with control.DesignSecondary data analysis of a 7-month school-based, cluster-randomized trial.Participants/settingThird- and fourth-grade students (n = 502, mean age: 9.0 ± 0.62 years) at 10 public elementary schools in Eastern Massachusetts (school year 2012-2013).InterventionGTLW included a 22-lesson classroom curriculum, homework activities, monthly parent newsletters, a food shopping and packing guide for parents, food demonstrations, school-wide announcements, and a poster contest.Main outcome measuresThe energy content of foods brought to school was estimated from digital photographs, and foods were assigned to 1 of 3 processing levels (less processed or unprocessed, moderately processed, or highly processed) based on an established classification system.Statistical analyses performedThe percentage of energy brought from foods categorized into each processing level was calculated and compared pre- and postintervention using hierarchical linear models.ResultsMost of the food brought from home to school was highly processed (70% of food energy brought). Foods categorized as snack foods and desserts contributed the greatest percentage of total energy to the highly processed category at baseline and follow-up (72% and 69%, respectively). Energy from foods brought for snack tended to be more highly processed than those brought for lunch. No significant differences were observed from pre- to postintervention in the GTLW group compared with control for the percentage of energy brought from highly processed foods in adjusted models (β: −1.1, standard error: 2.2, P = .6) or any other processing level.ConclusionsHighly processed foods were prevalent in home-packed lunches and snacks, and these patterns persisted after a targeted intervention. Further research is needed to identify strategies to improve the healthfulness of foods brought from home to school.     

Reproducibility and relative validity of a food frequency questionnaire to assess intake of dietary flavonol and flavone in Chinese university campus population

Epidemiologic studies have shown that populations that consume more fruits and vegetables have lower incidences of some diseases. These health effects have largely been attributed to flavonoid intake and bioavailability. However, no published data on the estimated flavonol and flavone intake of Chinese adults are currently available. Considering reports that food frequency questionnaires (FFQs) have been shown to provide good measurements of energy, macronutrient, and micronutrient intakes, we hypothesized that FFQ may be used to estimate intake of dietary flavonol and flavone. The two 7-day 24-hour dietary recalls (24-HDRs) and plasma levels were used as reference criteria. A total of 128 subjects each completed two 7-day 24-HDR and 2 FFQs, and 92 subjects donated 2 plasma samples. Pearson correlation coefficients and the agreement of quartile categorization between the FFQ and each reference instrument were conducted. Pearson correlation coefficients between 2 FFQs were 0.62 for flavonol and 0.65 for flavone and ranged from 0.48 (quercetin) to 0.63 (luteolin) (all P < .05). Pearson correlation coefficients between FFQ and 24-HDR were 0.62 for flavonol and 0.68 for flavone and ranged from 0.36 (quercetin) to 0.63 (luteolin) (all P < .05). Between the FFQ and plasma samples, Pearson correlation coefficients were 0.52 for flavonol and 0.41 for flavone and ranged from 0.32 (quercetin) to 0.44 (kaempferol) (all P < .05). The complete and partial agreement by quartiles ranged from 70% to 89%. The findings indicate that administering FFQ is a reliable and accurate method of assessing dietary intake of flavonol and flavone.     

Food patterns of Australian children ages 9 to 13 y in relation to ω-3 long chain polyunsaturated intake

ObjectiveThe aim of this study was to examine food patterns of Australian children ages 9 to 13 y in relation to ω-3 long-chain polyunsaturated fatty acid (ω-3 LCPUFA) intake.MethodsSecondary analysis was conducted on nationally representative food data of 1110 Australian children ages 9 to 13 y (525 boys and 585 girls) that was obtained using two 24-h recalls. Principle component factor analysis was used to identify food patterns. Discriminant function analysis was used to identify the relationship between the food patterns and total ω-3 LCPUFA intake.ResultsFour major food patterns emerged for each sex. For boys these were labeled: “snack foods,” “soft drinks,” “vegetables,” and “pork and meat chops, steak, and mince.” For girls they were labeled: “vegetables,” “take-away,” “tea, coffee, iced coffee drinks” and “canned meals and soup.” Fish consumption bought from take-away outlets was more frequently consumed in the “soft drink” (r = 0.577) and take-away (r = 0.485) food pattern in boys and girls, respectively. In contrast, fish prepared at home was more often consumed in “vegetables” in both boys (r = 0.018) and girls (r = 0.106), as well as in the “pork and meat chops, steak and mince” food pattern in boys (r = 0.060). There was a trend that in boys, the “vegetables” group discriminated children who consumed ω-3 LCPUFA levels similar to adequate intakes (AI) (P = 0.067), whereas in girls, the take-away food pattern discriminated for being a fish consumer (P = 0.060).ConclusionsDietary patterns associated with a high consumption of vegetables and “take-aways” food that include meat and fish are likely to positively influence dietary ω-3 LCPUFA intake in Australian children.     

The use of novel foods enriched with long-chain n-3 fatty acids to increase dietary intake: a comparison of methodologies assessing nutrient intake

OBJECTIVE: To evaluate the effect of consuming a variety of foods enriched in long-chain n-3 fatty acids in low fish eaters. DESIGN: Evaluation of reported dietary intakes in a 6-month, double-blind, randomized, controlled parallel design trial. SUBJECTS/SETTING: Eighty-five men and women with overweight and mildly elevated triglyceride levels who have a low habitual intake of fish. INTERVENTION: Subjects were randomized to consume foods either enriched in long-chain n-3 fats or control foods (not enriched). Subjects were asked to consume eight portions per day (equivalent to approximately 1 g/day long-chain n-3 fatty acid if randomized to the intervention). MAIN OUTCOME MEASURE: Reported energy, macronutrient, and fatty acid intakes were measured by diet history, 3-day food records, and body weight. STATISTICAL ANALYSES: Repeated measures analysis of variance, Kruskall-Wallis test, Pearson's correlation coefficient, and Bland-Altman plots were conducted. RESULTS: The two groups did not differ in mean dietary intake of long-chain n-3 fatty acid intake at baseline (258 mg and 313 mg for the intervention and control groups, respectively). At 6 months the intervention group members increased their intake of long-chain n-3 fats 4.5-fold compared with baseline and with the control group (P<.001). The data from the diet histories correlated well with the food records for all reported macronutrient and fatty acid values. Food pattern analysis showed that milk (13.8%), cereal (12.1%), and bread (11.3%) contributed the most to the overall long-chain n-3 fatty acid intake in the intervention group. CONCLUSIONS: This long-term study in free-living subjects indicates that population intakes of long-chain n-3 fatty acids could be substantially increased through the availability of a variety of n-3 fatty acid-enriched processed foods.     

Associations among Omega-3 Fatty Acid Status,Anxiety, and Mental Toughness in Female Collegiate Athletes

Objective: Poor omega-3 fatty acid status has been linked to anxiety in the general population, but scarce data are available describing omega-3 fatty acid levels in athletes and their associations with anxiety and mental toughness.

Methods: Whole blood samples were obtained from 54 female collegiate athletes and analyzed for fatty acids as a part of this cross-sectional observational study. Participants also completed a food frequency questionnaire on the intake of omega-3 fatty acids, as well as the Beck Anxiety Inventory (BAI), Sport Anxiety Scale (SAS)-2, and Mental Toughness Scale (MTS). Measures were collected during the athletes' off-season. Spearman's rho coefficients were used to examine the associations between fatty acid levels and psychological scores.

Results: Blood levels of the HS-Omega-3 Index® (rho = ?0.32, p = 0.02), eicosapentaenoic acid (rho = ?0.40, p = 0.003), and docosapentaenoic acid (rho = ?0.33, p = 0.02) were negatively correlated with BAI scores. Likewise, dietary intakes of eicosapentaenoic acid (rho = ?0.38, p = 0.007) and docosahexaenoic acid (rho = ?0.35, p = 0.02) were negatively correlated with BAI scores. Blood docosapentaenoic acid was positively correlated with MTS (rho = 0.27, p = 0.049). None of the dietary or blood fatty acids were significantly correlated with SAS-2 scores.

Conclusions: Both blood and dietary omega-3 fatty acid levels are associated with general but not sport-specific anxiety in female collegiate athletes during an off-season period. Randomized trials should be conducted to evaluate the effects of omega-3 fatty acid supplementation on anxiety and mental toughness in athletes.     

Validation of a food frequency questionnaire to assess intake of n-3 polyunsaturated fatty acids in subjects with and without major depressive disorder

The role of n-3 polyunsaturated fatty acids (PUFAs) in psychiatric illness is a topic of public health importance. This report describes development and biomarker validation of a 21-item, self-report food frequency questionnaire (FFQ) intended for use in psychiatric research to assess intake of α-linolenic acid (18:3n-3 [ALA]), docosahexaenoic acid (22:6n-3 [DHA]), and eicosapentaenoic acid (20:5n-3 [EPA]). In a cross-sectional study conducted from September 2006 to September 2008, sixty-one ethnically diverse adult participants with (n=34) and without (n=27) major depressive disorder completed this n-3 PUFA FFQ and provided a plasma sample. Plasma levels of n-3 PUFAs EPA and DHA, and n-6 PUFA arachidonic acid (20:4n-6 [AA]) were quantified by gas chromatography. Using Spearman's ρ, FFQ-estimated intake correlated with plasma levels of DHA (r=0.50; P<0.0001) and EPA (r=0.38; P=0.002), but not with ALA levels (r=0.22; P=0.086). Participants were classified into quartiles by FFQ-estimated intake and plasma PUFA concentrations. Efficacy of the FFQ to rank individuals into same or adjacent plasma quartiles was 83% for DHA, 78.1% for EPA, and 70.6% for ALA; misclassification into extreme quartiles was 4.9% for DHA, 6.5% for EPA, and 8.2% for ALA. FFQ-estimated EPA intake and plasma EPA were superior to plasma AA levels as predictors of the plasma AA to EPA ratio. This brief FFQ can provide researchers and clinicians with valuable information concerning dietary intake of DHA and EPA.     

Association between serum trans-monounsaturated fatty acids and breast cancer risk in the E3N-EPIC Study

The authors assessed the association between serum phospholipid fatty acids as biomarkers of fatty acid intake and breast cancer risk among women in the E3N Study (1989-2002), the French component of the European Prospective Investigation into Cancer and Nutrition. During an average of 7 years of follow-up, 363 cases of incident invasive breast cancer were documented among 19,934 women who, at baseline (1995-1998), had completed a diet history questionnaire and provided serum samples. Controls were randomly matched to cases by age, menopausal status at blood collection, fasting status at blood collection, date, and collection center. Serum phospholipid fatty acid composition was assessed by gas chromatography. Adjusted odds ratios for risk of breast cancer with increasing levels of fatty acids were calculated using conditional logistic regression. An increased risk of breast cancer was associated with increasing levels of the trans-monounsaturated fatty acids palmitoleic acid and elaidic acid (highest quintile vs. lowest: odds ratio = 1.75, 95% confidence interval: 1.08, 2.83; p-trend = 0.018). cis-Monounsaturated fatty acids were unrelated to breast cancer risk. A high serum level of trans-monounsaturated fatty acids, presumably reflecting a high intake of industrially processed foods, is probably one factor contributing to increased risk of invasive breast cancer in women.