Validity of the assessment of dietary intake: problems of misreporting

Dietary intake of heme iron and risk of cardiovascular disease: a dose-response meta-analysis of prospective cohort studies

BACKGROUND AND AIMS

Iron is thought to play a fundamentally important role in the development of cardiovascular disease (CVD). This meta-analysis was performed to investigate the dose-response association between dietary intake of iron (including heme and non-heme iron) and the risk of CVD.

METHODS AND RESULTS

We performed a search of the PubMed and Embase databases for prospective cohort studies of the association between dietary iron intake and CVD risk. Thirteen articles comprising 252,164 participants and 15,040 CVD cases were eligible for inclusion. Heme iron intake was associated significantly with increased risk of cardiovascular disease, and the pooled relative risk (RR) for each 1 mg/day increment was 1.07 (95% confidence interval: 1.01 to 1.14, I² = 59.7%). We also found evidence of a curvilinear association (P < 0.05 for non-linearity). In contrast, we found no association between CVD risk and dietary non-heme (0.98, 0.96 to 1.01, I² = 15.8%) or total iron (1.00, 0.94 to 1.06, I² = 30.4%). Subgroup analyses revealed that the association between heme iron intake and CVD risk was stronger among non-fatal cases (1.19, 1.07-1.33) and American patients (1.31, 1.11-1.56).

CONCLUSIONS

Higher dietary intake of heme iron is associated with an increased risk of cardiovascular disease, whereas no association was found between CVD and non-heme iron intake or total iron intake. These findings may have important public health implications with respect to preventing cardiovascular disease.

Energy requirements of adult dogs: a meta-analysis

A meta-analysis was conducted to determine the maintenance energy requirements of adult dogs. Suitable publications were first identified, and then used to generate relationships amongst energy requirements, husbandry, activity level, methodology, sex, neuter status, dog size, and age in healthy adult dogs. Allometric equations for maintenance energy requirements were determined using log-log linear regression. So that the resulting equations could readily be compared with equations reported by the National Research Council, maintenance energy requirements in the current study were determined in kcal/kg(0.75) body weight (BW). Ultimately, the data of 70 treatment groups from 29 publications were used, and mean (± standard deviation) maintenance energy requirements were 142.8±55.3 kcal·kgBW(-0.75)·day(-1). The corresponding allometric equation was 81.5 kcal·kgBW(-0.9)·day(-1) (adjusted R2 = 0.64; 70 treatment groups). Type of husbandry had a significant effect on maintenance energy requirements (P<0.001): requirements were greatest in racing dogs, followed by working dogs and hunting dogs, whilst the energy requirements of pet dogs and kennel dogs were least. Maintenance energy requirements were less in neutered compared with sexually intact dogs (P<0.001), but there was no effect of sex. Further, reported activity level tended to effect the maintenance energy requirement of the dog (P = 0.09). This review suggests that estimating maintenance energy requirements based on BW alone may not be accurate, but that predictions that factor in husbandry, neuter status and, possibly, activity level might be superior. Additionally, more information on the nutrient requirements of older dogs, and those at the extremes of body size (i.e. giant and toy breeds) is needed.

Changes in beverage consumption from pre-pregnancy to early pregnancy in the Norwegian Fit for Delivery study

OBJECTIVE

To describe changes in consumption of different types of beverages from pre-pregnancy to early pregnancy, and to examine associations with maternal age, educational level and BMI.

DESIGN

Cross-sectional design. Participants answered an FFQ at inclusion into a randomized controlled trial, the Fit for Delivery (FFD) trial, in median gestational week 15 (range: 9-20), reporting current consumption and in retrospect how often they drank the different beverages pre-pregnancy.

SETTING

Eight local antenatal clinics in southern Norway from September 2009 to February 2013.

SUBJECTS

Five hundred and seventy-five healthy pregnant nulliparous women.

RESULTS

Pre-pregnancy, 27 % reported drinking alcohol at least once weekly, compared with none in early pregnancy (P<0.001). The percentage of women drinking coffee (38 % v. 10 %, P<0.001), sugar-sweetened beverages (10 % v. 6 %, P=0.011) and artificially sweetened beverages (12 % v. 9 %, P=0.001) at least daily decreased significantly from pre-pregnancy to early pregnancy, while the percentage of women who reported to drink water (85 % v. 92 %, P<0.001), fruit juice (14 % v. 20 %, P=0.001) and milk (37 % v. 42 %, P=0.001) at least daily increased significantly. From pre-pregnancy to early pregnancy higher educated women reduced their consumption frequency of coffee significantly more than women with lower education. Older women reduced their consumption frequency of coffee and artificially sweetened beverages and increased their consumption frequency of fruit juice and milk significantly more than younger women.

CONCLUSIONS

There is a significant change in beverage consumption from pre-pregnancy to early pregnancy among Norwegian nulliparous women.

Usual energy and macronutrient intakes in 2-9-year-old European children

OBJECTIVE

Valid estimates of population intakes are essential for monitoring trends as well as for nutritional interventions, but such data are rare in young children. In particular, the problem of misreporting in dietary data is usually not accounted for. Therefore, this study aims to provide accurate estimates of intake distributions in European children.

DESIGN

Cross-sectional setting-based multi-centre study.

SUBJECTS

A total of 9560 children aged 2-9 years from eight European countries with at least one 24-h dietary recall (24-HDR).

METHODS

The 24-HDRs were classified in three reporting groups based on age- and sex-specific Goldberg cutoffs (underreports, plausible reports, overreports). Only plausible reports were considered in the final analysis (N=8611 children). The National Cancer Institute (NCI)-Method was applied to estimate population distributions of usual intakes correcting for the variance inflation in short-term dietary data.

RESULTS

The prevalence of underreporting (9.5%) was higher compared with overreporting (3.4%). Exclusion of misreports resulted in a shift of the energy and absolute macronutrient intake distributions to the right, and further led to the exclusion of extreme values, that is, mean values and lower percentiles increased, whereas upper percentiles decreased. The distributions of relative macronutrient intakes (% energy intake from fat/carbohydrates/proteins) remained almost unchanged when excluding misreports. Application of the NCI-Method resulted in markedly narrower intake distributions compared with estimates based on single 24-HDRs. Mean percentages of usual energy intake from fat, carbohydrates and proteins were 32.2, 52.1 and 15.7%, respectively, suggesting the majority of European children are complying with common macronutrient intake recommendations. In contrast, total water intake (mean: 1216.7 ml per day) lay below the recommended value for >90% of the children.

CONCLUSION

This study provides recent estimates of intake distributions of European children correcting for misreporting as well as for the daily variation in dietary data. These data may help to assess the adequacy of young children's diets in Europe.

Consuming a buttermilk drink containing lutein-enriched egg yolk daily for 1 year increased plasma lutein but did not affect serum lipid or lipoprotein concentrations in adults with early signs of age-related macular degeneration

Dietary lutein intake is postulated to interfere with the development of age-related macular degeneration (AMD). Because egg yolk-derived lutein has a high bioavailability, long-term consumption of lutein-enriched eggs might be effective in preventing AMD development, but alternatively might increase cardiovascular disease risk. Here, we report the effect of 1-y daily consumption of a buttermilk drink containing 1.5 lutein-rich egg yolks on serum lipid and lipoprotein and plasma lutein concentrations. Additionally, subgroups that could potentially benefit the most from the intervention were identified. Men and women who had early signs of AMD in at least 1 eye, but were otherwise healthy, participated in a 1-y randomized, placebo-controlled parallel intervention trial. At the start of the study, 101 participants were included: 52 in the experimental (Egg) group and 49 in the control (Con) group. Final analyses were performed with 45 participants in the Egg group and 43 participants in the Con group. As expected, the increase in plasma lutein concentrations in the Egg group was 83% higher than that in the Con group (P < 0.001). Changes in serum total, HDL, and LDL cholesterol, as well as the ratio of total cholesterol to HDL cholesterol, were not different between the 2 groups. Interestingly, participants classified as cholesterol absorbers had higher serum HDL cholesterol concentrations than participants classified as cholesterol synthesizers or participants with average campesterol-to-lathosterol ratios (P < 0.05) at baseline. In addition, cholesterol absorbers had a 229% higher increase in plasma lutein concentrations than participants who were classified as having an average campesterol-to-lathosterol ratio upon consumption of the lutein-enriched egg yolk drink (P < 0.05). Moreover, the change in serum HDL cholesterol upon consumption was significantly different between these 3 groups (P < 0.05). We suggest that cholesterol absorbers particularly might benefit from the lutein-enriched buttermilk drink. This study was registered at clinicaltrials.gov as NCT00902408.

Dietary intake assessment in women with different weight and pregnancy status using a short questionnaire

OBJECTIVE

First, to evaluate the ability of a short dietary questionnaire (SDQ) to estimate energy intake (EI) on group and individual levels compared with total energy expenditure (TEE) measured by the doubly labelled water method. Second, to compare the SDQ's performance in estimating energy, nutrient and food intakes with a sixty-six-item FFQ used in large-scale Swedish epidemiological research.

DESIGN

Cross-sectional.

SETTING

Umeå, Sweden.

SUBJECTS

In total, sixty-five non-pregnant women, of whom thirty-one were overweight or obese, and twenty-five pregnant, normal-weight women completed the protocol.

RESULTS

On average, the SDQ captured 78 % and 79 % of absolute TEE in the non-pregnant and pregnant normal-weight women, respectively. Furthermore, the SDQ captured an average of 57 % of TEE in the overweight/obese non-pregnant women. The Spearman correlation of EI and TEE was significant in the overweight and obese women only (ρ = 0·37, 95 % CI 0·02, 0·64). There was no significant difference between the SDQ and the more extensive FFQ in the ability to assess EI when compared with TEE. Intakes of most nutrients and foods were significantly higher when assessed with the SDQ compared with the FFQ.

CONCLUSIONS

A new short dietary questionnaire with an alternative design underestimated EI of non-pregnant and pregnant, overweight and obese women on a group level but was able to rank the overweight/obese women according to EI. Furthermore, the short questionnaire captured as much or more of the energy, nutrient and food intakes of non-pregnant normal-weight and overweight/obese women on the group level as a traditional, more extensive FFQ.

Patterns of nutrients' intake at six months in the northeast of Italy: a cohort study

BACKGROUND

Adequate complementary feeding is recognized as an important predictor of health later in life. The objective of this study was to describe the feeding practices and nutrients' intake, and their association with breastfeeding at six months of age, in a cohort of infants enrolled at birth in the maternity hospital of Trieste, Italy.

METHODS

Out of 400 infants enrolled at birth, 268 (67%) had complete data gathered through a 24-hour feeding diary on three separate days at six months, and two questionnaires administered at birth and at six months. Data from feeding diaries were used to estimate nutrients' intakes using the Italian food composition database included in the software. To estimate the quantity of breastmilk, information was gathered on the frequency and length of breastfeeds.

RESULTS

At six months, 70% of infants were breastfed and 94% were given complementary foods. The average daily caloric intake was higher in non-breastfed (723 Kcal) than in breastfed infants (547 Kcal, p < 0.001) due to energy provided by complementary foods (321 vs. 190 Kcal, p < 0.001) and milk (363 vs. 301 Kcal, p = 0.007). Non-breastfed infants had also higher intakes of carbohydrates, proteins, and fats. The mean intake of macronutrients was within recommended ranges in both groups, except for the higher protein intake in non-breastfed infants. These consumed significantly higher quantities of commercial baby foods than breastfed infants.

CONCLUSIONS

Contrary to what is recommended, 94% of infants were not exclusively breastfed and were given complementary foods at six months. The proportion of daily energy intake from complementary foods was around 50% higher than recommended and with significant differences between breastfed and non-breastfed infants, with possible consequences for future nutrition and health.

Weight loss maintenance in overweight subjects on ad libitum diets with high or low protein content and glycemic index: the DIOGENES trial 12-month results

BACKGROUND

A high dietary protein (P) content and low glycemic index (LGI) have been suggested to be beneficial for weight management, but long-term studies are scarce.

OBJECTIVE

The DIOGENES randomized clinical trial investigated the effect of P and GI on weight loss maintenance in overweight or obese adults in eight centers across Europe. This study reports the 1-year results in two of the centers that extended the intervention to 1 year.

METHOD

After an 8-week low-calorie diet (LCD), 256 adults (body mass index >27 kg m(-)(2)) were randomized to five ad libitum diets for 12 months: high P/LGI (HP/LGI), HP/high GI (HP/HGI), low P/LGI (LP/LGI), LP/HGI and a control diet. During the first 6 months, foods were provided for free through a shop system and during the whole 12-month period, subjects received guidance by a dietician. Primary outcome variable was the change in body weight over the 12-month intervention period.

RESULTS

During the LCD period, subjects lost 11.2 (10.8, 12.0) kg (mean (95% confidence interval (CI))). Average weight regain over the 12-month intervention period was 3.9 (95% CI 3.0-4.8) kg. Subjects on the HP diets regained less weight than subjects on the LP diets. The difference in weight regain after 1 year was 2.0 (0.4, 3.6) kg (P=0.017) (completers analysis, N=139) or 2.8 (1.4, 4.1) kg (P<0.001) (intention-to-treat analysis, N=256). No consistent effect of GI on weight regain was found. There were no clinically relevant differences in changes in cardiometabolic risk factors among diet groups.

CONCLUSION

A higher protein content of an ad libitum diet improves weight loss maintenance in overweight and obese adults over 12 months.

The effect of dietary counseling on nutrient intakes in gastric banding surgery patients

BACKGROUND

There is some evidence that bariatric surgery patients who undergo the purely restrictive procedures, such as the gastric banding (GB) or the vertical banded gastroplasty surgery, do not meet the dietary reference intakes for several nutrients. Whether dietary counseling improves micronutrient and macronutrient intakes was examined in GB surgery patients.

METHODS

Twenty-three GB surgery patients received dietary and behavioral counseling for 12 weeks to limit energy intake and improve nutrient intakes. Food intake was assessed by 3-day food record at baseline and 6 and 12 weeks. Postintervention data were available in 21 patients.

RESULTS

At baseline, more than 50% of the subjects reported inadequate dietary intakes of 13 nutrients but overconsumption of sodium and percent energy from saturated and trans-fatty acids. Mixed-effects model for repeated measures revealed a significant reduction in energy (P = 0.0007), absolute protein (P = 0.04), cholesterol (P = 0.045), and potassium (P = 0.01) intake and an increase in vitamin K (P = 0.03) intake and percent energy from protein (P = 0.005) during the 12 weeks. The McNemar test showed a reduction in the proportion of the subjects with an inadequate intake of vitamin K (P = 0.008) but an increase in the proportion of the subjects with an inadequate intake of thiamin (P = 0.03) at 12 weeks. The proportion of the subjects who did not meet the nutrient requirements for the remaining 27 nutrients was generally high and remained unchanged.

CONCLUSIONS

Dietary intervention improved the intake of some nutrients in the GB surgery patients. However, most nutrient intake requirements remained unmet by many subjects. These results indicate that nutritional counseling beyond 12 weeks is warranted in GB surgery patients to improve their dietary nutrient intakes.

Dietary beliefs and eating patterns influence metabolic health in type 2 diabetes: A clinic-based study in urban North India

BACKGROUND

Almost 15% of India's urban adult populace now lives with type 2 diabetes. This study aimed to characterize the eating patterns, knowledge, beliefs, and determinants of food choice, and assess associations with the metabolic health among urban Asian Indians with type 2 diabetes.

MATERIALS AND METHODS

A cross-sectional study of 258 individuals (mean age 55.7 ± 10 years; body mass index 27.1 ± 4.8 kg/m(2); diabetes duration 10.1 ± 6.5 years) attending two out-patient clinics in New Delhi, India. Food-related information was collected during a semi-structured interview. Clinical, anthropometric, and biochemical data were recorded.

RESULTS

Beliefs related to health and diabetes played a role determining food choice and dietary patterns; erroneous views were associated with the poor food choices and greater metabolic perturbations. Average consumption of fruits/vegetables was low. Intakes were positively associated with intentions to manage diabetes; inversely associated with the waist circumference and negatively correlated with one's degree of personal responsibility for food choice. Household saturated fat usage was common. High fat intakes were positively associated with the taste preference, ratings of perceived "health-value;" waist circumference, glycosylated haemoglobin percentage (HbA1c%) and lipids.

CONCLUSIONS

Strategies to enhance diabetes control among Asian Indians are required and should encourage fruit/vegetable intake, personal accountability, and consider individual beliefs and preferences. Greater emphasis and resources directed to regular dietary and behavioral counseling may assist.

Positive effect of mushrooms substituted for meat on body weight, body composition, and health parameters. A 1-year randomized clinical trial

Reducing energy density (ED) of the diet is an important strategy for controlling obesity. This 1-year, randomized clinical trial examined the effect of substituting mushrooms for red meat ('mushroom diet'), compared to a standard diet ('meat diet'), on weight loss and maintenance among 73 obese adults (64 women, 9 men). The subjects completed anthropometric measurements and 7-day food records four times during a standardized weight loss and maintenance regimen. At the end of the 1-year trial, compared to participants on the standard diet, participants on the mushroom diet (n=36) reported lower intakes of energy (mean ± [SE]=-123 ± 113 kcals) and fat (-4.25 ± 6.88 g), lost more pounds and percentage body weight (-7.03 ± 3.34 lbs, 3.6%), achieved lower body mass index (-1.53 ± 0.36), waist circumference (-2.6 ± 3.5 in.) and percent total body fat (-0.85 ± 0.53), and had lower systolic and diastolic pressure (-7.9 and -2.5 mmHg); their lipid profile and inflammatory markers also improved. After initial weight loss, subjects following the mushroom diet maintained that loss well. Those who completed the full 12-month trial still weighed a mean of 7 lbs less than baseline. Thus, encouraging adults to substitute mushrooms for red meat was a useful strategy for enhancing weight loss, weight maintenance, and health parameters.

Dietary supplement use and health-related behaviors in a Mediterranean population

OBJECTIVE

To determine predictors and health-related motivation for supplement use.

DESIGN

Population-based, cross-sectional survey. Food intake was determined by a validated food frequency questionnaire that included questions on dietary supplement consumption. Physical activity, smoking status, educational level, self-perceived mental and physical health, and medical information and drug treatment of diabetes, hypertension, and hypercholesterolemia were recorded. Weight and height were measured.

SETTING

Girona, Spain.

PARTICIPANTS

Six thousand three hundred fifty-two men and women aged 35-80 years.

ANALYSIS

Multiple logistic regression analysis to evaluate the association between dietary supplement use and the other variables.

RESULTS

Dietary supplements were consumed by 9.3% of the participants. Positive predictors of supplement use were female sex (odds ratio = 2.44, 95% confidence interval 1.96-3.04), higher educational level (P < .001), and a high adherence to the Mediterranean diet pattern (P < .001) and to the nutrient adequacy score (P = .004). A higher body mass index (P < .001) and the awareness of hypertension (odds ratio = 0.69, 95% confidence interval 0.56-0.87) were negatively associated with supplement use.

CONCLUSIONS AND IMPLICATIONS

The relatively small number of dietary supplement users did not show a clustering of healthy lifestyle habits. Self-perception of mental and physical health and awareness of a cardiometabolic disorder were not motivators for supplement use.

Sex differences in the physiology of eating

Hypothalamic-pituitary-gonadal (HPG) axis function fundamentally affects the physiology of eating. We review sex differences in the physiological and pathophysiological controls of amounts eaten in rats, mice, monkeys, and humans. These controls result from interactions among genetic effects, organizational effects of reproductive hormones (i.e., permanent early developmental effects), and activational effects of these hormones (i.e., effects dependent on hormone levels). Male-female sex differences in the physiology of eating involve both organizational and activational effects of androgens and estrogens. An activational effect of estrogens decreases eating 1) during the periovulatory period of the ovarian cycle in rats, mice, monkeys, and women and 2) tonically between puberty and reproductive senescence or ovariectomy in rats and monkeys, sometimes in mice, and possibly in women. Estrogens acting on estrogen receptor-α (ERα) in the caudal medial nucleus of the solitary tract appear to mediate these effects in rats. Androgens, prolactin, and other reproductive hormones also affect eating in rats. Sex differences in eating are mediated by alterations in orosensory capacity and hedonics, gastric mechanoreception, ghrelin, CCK, glucagon-like peptide-1 (GLP-1), glucagon, insulin, amylin, apolipoprotein A-IV, fatty-acid oxidation, and leptin. The control of eating by central neurochemical signaling via serotonin, MSH, neuropeptide Y, Agouti-related peptide (AgRP), melanin-concentrating hormone, and dopamine is modulated by HPG function. Finally, sex differences in the physiology of eating may contribute to human obesity, anorexia nervosa, and binge eating. The variety and physiological importance of what has been learned so far warrant intensifying basic, translational, and clinical research on sex differences in eating.

A comparison of the accuracy of self-reported intake with measured intake of a laboratory overeating episode in overweight and obese women with and without binge eating disorder

PURPOSE

Research has demonstrated significant underreporting of food intake in obese individuals with and without binge eating disorder (BED). An improved understanding of the accuracy of self-reported food intake is central to diagnosis of eating disorders and monitoring response to treatment. The purpose was to: (1) confirm those with BED consume significantly more kilocalories (kcal) than overweight/obese controls when instructed to overeat in the laboratory and (2) compare dietary recall data with measured intake.

METHODS

Fifteen women fulfilling BED criteria and 17 controls participated in an overeating episode and completed a 24-h dietary recall.

RESULTS

BED participants consumed significantly more kilocalories according to both methodologies. The BED group self-reported 90% of the measured intake compared to 98% for the control group. Mean differences between the methods indicated that on average both groups underreported intake; however, the mean difference between methods was significantly greater in the BED group.

CONCLUSIONS

Findings confirm that those with BED consume significantly more than controls during a laboratory binge and controls tended to be more accurate in recalling their intake 24 h later.

Underreporting in obese inpatients undergoing a psycho-nutritional rehabilitative program

OBJECTIVE

To evaluate the possible correlation between underreporting and anthropometric, psychological and socio-anagraphic characteristics in obese inpatients.

DESIGN

Perspective longitudinal study.

SUBJECTS

Forty-two obese inpatients enrolled to a multidisciplinary 3-week weight loss program in a psycho-nutritional rehabilitative structure located in Salice Terme, Northern Italy. They underwent anthropometric, dietary, clinical, and psycho diagnostic evaluation.

RESULTS

Forty-two subjects were included in the study of which 29 (70 %) were females and 13 were males. Mean BMI and mean waist circumference were 42.7 ± 9.5 kg/m(2) and 125 ± 18 cm, respectively. The mean weight loss of 4.2 ± 2.2 kg in the whole sample was significantly greater in males compared to females. The waist circumference fell in equal measure in both of the sexes. Thirty patients were classified as underreporters according to Goldberg, two-thirds of which were females. In the course of the three recovery weeks, a third of the 30 subjects identified as underreporters at the beginning continued to underreport energy intake.

CONCLUSION

In our study, the prevalence of underreporting was equal to over 70 % of the original sample. There was no significant difference between the weight losses achieved by the underreporter and non-underreporter groups. All the underreporters initially became partly non-underreporters during treatment. Those who gave up the practice of underreporting were patients who had a more elevated BMI, who were more susceptible to binge eating behavior and who experienced a strong uneasiness both physically and psychologically. They also had a strongly impaired quality of life.

Under-reporting of energy intake in elderly Australian women is associated with a higher body mass index

OBJECTIVES

Identify the extent of under-reporting of energy intake and the characteristics associated with implausible intakes in elderly women.

DESIGN

Dietary intake was assessed using a 3-day weighed food record. Protein intake was validated by 24-hour urinary nitrogen. To examine under-reporting, participants were grouped according to their energy intake and compared to the Goldberg cut-off equation. Logistic regression was performed to assess the influence of body mass index (BMI) and social-demographic factors on under-reporting.

SETTING

Community dwelling elderly women from Perth, Western Australia.

PARTICIPANTS

217 elderly women aged 70-80 years.

RESULTS

Under-reporters had a higher physical activity level (p<0.001) compared with acceptable-reporters. The under-reporters also had a higher body weight (p=0.006), body mass index (BMI) (p=0.001), waist (p=0.011), hip circumference (p<0.001), whole body fat mass (p<0.001) and percentage body fat (p<0.001) than acceptable-reporters. Under-reporters had a significantly lower intakes of protein, fat, carbohydrate and alcohol (p<0.001) and fewer reported food items, compared with acceptable reporters. However, 24-hour urinary nitrogen was only marginally different between the two groups (p=0.053). Participants with a higher BMI were more likely to under-report their energy intake (BMI=25-29.9: odds ratio=2.98[95% CI=1.46-6.09]; BMI≥30: 5.84[2.41-14.14]).

CONCLUSION

Under-reporting energy intake in elderly women was associated with a higher BMI, body fat and higher self-reported physical activity levels. A higher BMI (≥25) appears to be most significant factor in determining if elderly women will underreport their food intake and may be related to body image. These results have implications for undertaking surveys of food intake in elderly women.

Egg consumption and risk of coronary heart disease and stroke: dose-response meta-analysis of prospective cohort studies

OBJECTIVE

To investigate and quantify the potential dose-response association between egg consumption and risk of coronary heart disease and stroke.

DESIGN

Dose-response meta-analysis of prospective cohort studies.

DATA SOURCES

PubMed and Embase prior to June 2012 and references of relevant original papers and review articles.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Prospective cohort studies with relative risks and 95% confidence intervals of coronary heart disease or stroke for three or more categories of egg consumption.

RESULTS

Eight articles with 17 reports (nine for coronary heart disease, eight for stroke) were eligible for inclusion in the meta-analysis (3,081,269 person years and 5847 incident cases for coronary heart disease, and 4,148,095 person years and 7579 incident cases for stroke). No evidence of a curve linear association was seen between egg consumption and risk of coronary heart disease or stroke (P=0.67 and P=0.27 for non-linearity, respectively). The summary relative risk of coronary heart disease for an increase of one egg consumed per day was 0.99 (95% confidence interval 0.85 to 1.15; P=0.88 for linear trend) without heterogeneity among studies (P=0.97, I(2)=0%). For stroke, the combined relative risk for an increase of one egg consumed per day was 0.91 (0.81 to 1.02; P=0.10 for linear trend) without heterogeneity among studies (P=0.46, I(2)=0%). In a subgroup analysis of diabetic populations, the relative risk of coronary heart disease comparing the highest with the lowest egg consumption was 1.54 (1.14 to 2.09; P=0.01). In addition, people with higher egg consumption had a 25% (0.57 to 0.99; P=0.04) lower risk of developing hemorrhagic stroke.

CONCLUSIONS

Higher consumption of eggs (up to one egg per day) is not associated with increased risk of coronary heart disease or stroke. The increased risk of coronary heart disease among diabetic patients and reduced risk of hemorrhagic stroke associated with higher egg consumption in subgroup analyses warrant further studies.

Effects of energy-restricted high-protein, low-fat compared with standard-protein, low-fat diets: a meta-analysis of randomized controlled trials

BACKGROUND

It is currently unclear whether altering the carbohydrate-to-protein ratio of low-fat, energy-restricted diets augments weight loss and cardiometabolic risk markers.

OBJECTIVE

The objective was to conduct a systematic review and meta-analysis of studies that compared energy-restricted, isocaloric, high-protein, low-fat (HP) diets with standard-protein, low-fat (SP) diets on weight loss, body composition, resting energy expenditure (REE), satiety and appetite, and cardiometabolic risk factors.

DESIGN

Systematic searches were conducted by using MEDLINE, EMBASE, PubMed, and the Cochrane Central Register of Controlled Trials to identify weight-loss trials that compared isocalorically prescribed diets matched for fat intake but that differed in protein and carbohydrate intakes in participants aged ≥18 y. Twenty-four trials that included 1063 individuals satisfied the inclusion criteria.

RESULTS

Mean (±SD) diet duration was 12.1 ± 9.3 wk. Compared with an SP diet, an HP diet produced more favorable changes in weighted mean differences for reductions in body weight (-0.79 kg; 95% CI: -1.50, -0.08 kg), fat mass (FM; -0.87 kg; 95% CI: -1.26, -0.48 kg), and triglycerides (-0.23 mmol/L; 95% CI: -0.33, -0.12 mmol/L) and mitigation of reductions in fat-free mass (FFM; 0.43 kg; 95% CI: 0.09, 0.78 kg) and REE (595.5 kJ/d; 95% CI: 67.0, 1124.1 kJ/d). Changes in fasting plasma glucose, fasting insulin, blood pressure, and total, LDL, and HDL cholesterol were similar across dietary treatments (P ≥ 0.20). Greater satiety with HP was reported in 3 of 5 studies.

CONCLUSION

Compared with an energy-restricted SP diet, an isocalorically prescribed HP diet provides modest benefits for reductions in body weight, FM, and triglycerides and for mitigating reductions in FFM and REE.

Thermal stress in North Western Australian iron ore mining staff

INTRODUCTION

Demand for Australian mined iron ore has increased employment within this sector, thus exposing increased numbers of workers to the harsh Australian climate. This study examined the influence of hot (>30°C wet bulb globe temperature) environmental temperatures, consistent with working in North Western Australia, on iron ore mining staff.

METHODS

Core temperature, hydration status, perceived exertion, mood, and fatigue state were measured in 77 participants at three time points (pre-, mid-, and post-shift) during a normal 12-h shift at an open-cut iron ore mining/processing site (n = 31; Site1) and an iron ore processing/shipping site (n = 46; Site2).

RESULTS

A significant effect for time was observed for core temperature with greater mean core temperatures measured mid-shift (37.5±0.4°C) and post-shift (37.6±0.3°C) compared with pre-shift values (37.0±0.5°C). All mean core temperature measures were lower than ISO7933 thresholds (38°C) for thermal safety. Mean hydration measures [urine-specific gravity (USG)] were greater at Site1 (1.029±0.006) compared with those at Site2 (1.021±0.007). Furthermore, both pre- and post-shift measures from Site1 and the post-shift measures from Site2 were greater than the threshold for dehydration (USG = 1.020). No differences were observed for mood or perceived exertion over time; however, measures of fatigue state were greater post-shift compared with pre- and mid-shift values for both sites.

CONCLUSIONS

Our findings indicate that the majority of mine workers in North Western Australia are able to regulate work rate in hot environments to maintain core temperatures below ISO safety guidelines; however, 22% of workers reached or exceeded the safety guidelines, warranting further investigation. Furthermore, hydration practices, especially when off-work, appear inadequate and could endanger health and safety.

Low serum magnesium and the development of atrial fibrillation in the community: the Framingham Heart Study

BACKGROUND

Low serum magnesium has been linked to increased risk of atrial fibrillation (AF) after cardiac surgery. It is unknown whether hypomagnesemia predisposes to AF in the community.

METHODS AND RESULTS

We studied 3530 participants (mean age, 44 years; 52% women) from the Framingham Offspring Study who attended a routine examination and were free of AF and cardiovascular disease. We used Cox proportional hazard regression analysis to examine the association between serum magnesium at baseline and risk of incident AF. Analyses were adjusted for conventional AF risk factors, use of antihypertensive medications, and serum potassium. During up to 20 years of follow-up, 228 participants developed AF. Mean serum magnesium was 1.88 mg/dL. The age- and sex-adjusted incidence rate of AF was 9.4 per 1000 person-years (95% confidence interval, 6.7-11.9) in the lowest quartile of serum magnesium (≤1.77 mg/dL) compared with 6.3 per 1000 person-years (95% confidence interval, 4.1-8.4) in the highest quartile (≥1.99 mg/dL). In multivariable-adjusted models, individuals in the lowest quartile of serum magnesium were ~50% more likely to develop AF (adjusted hazard ratio, 1.52; 95% confidence interval, 1.00-2.31; P=0.05) compared with those in the upper quartiles. Results were similar after the exclusion of individuals on diuretics.

CONCLUSIONS

Low serum magnesium is moderately associated with the development of AF in individuals without cardiovascular disease. Because hypomagnesemia is common in the general population, a link with AF may have potential clinical implications. Further studies are warranted to confirm our findings and to elucidate the underlying mechanisms.

Diet–obesity associations in children: approaches to counteract attenuation caused by misreporting

Objective

Measurement errors in dietary data lead to attenuated estimates of associations between dietary exposures and health outcomes. The present study aimed to compare and evaluate different approaches of handling implausible reports by exemplary analysis of the association between dietary intakes (total energy, soft drinks, fruits/vegetables) and overweight/obesity in children.

Design

Cross-sectional multicentre study.

Setting

Kindergartens/schools from eight European countries participating in the IDEFICS Study.

Subjects

Children (n 5357) aged 2–9 years who provided one 24 h dietary recall and complete covariate information.

Results

The 24 h recalls were classified into three reporting groups according to adapted Goldberg cut-offs: under-report, plausible report or over-report. In the basic logistic multilevel model (adjusted for age and sex, including study centre as random effect), the dietary exposures showed no significant association with overweight/obesity (energy intake: OR=0·996 (95 % CI 0·983, 1·010); soft drinks: OR = 0·999 (95 % CI 0·986, 1·013)) and revealed even a positive association for fruits/vegetables (OR = 1·009 (95 % CI 1·001, 1·018)). When adding the reporting group (dummy variables) and a propensity score for misreporting as adjustment terms, associations became significant for energy intake as well as soft drinks (energy: OR = 1·074 (95 % CI 1·053, 1·096); soft drinks: OR = 1·015 (95 % CI 1·000, 1·031)) and the association between fruits/vegetables and overweight/obesity pointed to the reverse direction compared with the basic model (OR = 0·993 (95 % CI 0·984, 1·002)).

Conclusions

Associations between dietary exposures and health outcomes are strongly affected or even masked by measurement errors. In the present analysis consideration of the reporting group and inclusion of a propensity score for misreporting turned out to be useful tools to counteract attenuation of effect estimates.

Dairy intake and related self-regulation improved in college students using online nutrition education

BACKGROUND

Dairy intake by college students is markedly lower than recommendations. Interventions to improve dairy intake based on Social Cognitive Theory (SCT) have potential to successfully change behavior by improving mediators that influence dietary choices.

OBJECTIVE

We aimed to use SCT to improve social support, self-efficacy, outcome expectations, self-regulation, and behavior related to dairy intake in college students.

DESIGN

We conducted a randomized nutrition education intervention.

PARTICIPANTS/SETTING

Participants included 211 college students (mean age 20.2 ± 0.1 years; 63% women and 37% men) recruited from a university campus. Participants in the intervention group (n=107) and comparison group (n=104) received an 8-week dairy intake or stress management intervention, respectively, via electronic mail. Data collection included dairy intake from 7-day food records and SCT variables from questionnaires administered during January 2008 and April 2008.

MAIN OUTCOME MEASURES

Changes in dairy intake and SCT variables (ie, social support, self-efficacy, outcome expectations, and self-regulation).

STATISTICAL ANALYSES PERFORMED

Multivariate analysis of covariance, with age and sex as covariates (P<0.05).

RESULTS

Ninety-one percent of participants (n=97 intervention, n=94 comparison) provided data; complete data were analyzed for 85% of participants (n=90 intervention, n=89 comparison). Participants in the intervention group reported higher intake of total dairy foods (P=0.012) and improved use of self-regulation strategies for consuming three servings per day of total dairy (P=0.000) and low-fat dairy foods (P=0.002) following the intervention.

CONCLUSIONS

Nutrition education via electronic mail based on an SCT model improved total dairy intake and self-regulation. Participants reported increased dairy intake and better use of self-regulation strategies. Future interventions should focus on benefits of consuming low-fat vs higher-fat dairy foods.

Factors That Influence Food Amount Ratings by White, Hispanic, and Asian Samples

OBJECTIVE

Two studies explored in nonclinical samples variables that may influence meal size assessments.

RESEARCH METHODS AND PROCEDURES

In Study 1, the contribution of dietary restraint, weight, depressive symptoms, and gender to ratings on the Food Amount Rating Scale was examined in 153 white women and 121 white men; in Study 2, the contribution of dietary restraint, weight, ethnicity, and ethnic group identification to Food Amount Rating Scale ratings was examined in 67 Asian, 81 Hispanic, and 107 white women.

RESULTS

Study 1 indicated that food amounts were rated as larger when rated by male rather than female raters (male rater, mean=62.37, SD=1.14; female rater, mean=59.28, SD=0.89), for female rather than male targets (male target, mean=56.16, SD=0.97; female target, mean=64.87, SD=1.02), and by restrained rather than unrestrained eaters (restrained, mean=63.14, SD=1.11; unrestrained, mean=58.69, SD=0.91). Study 2 indicated that food amounts were rated as larger when rated by restrained eaters (restrained, mean=67.53, SD=1.21; unrestrained, mean=64.99, SD=1.09), Hispanic women (Asian, mean=64.59, SD=1.61; Hispanic, mean=68.71, SD=1.30; white, mean=65.41, SD=1.34), and underweight women (underweight, mean=70.38, SD=1.68; normal weight, mean=64.52, SD=0.93; overweight: mean=64.23, SD=1.64).

DISCUSSION

Food amount judgments may be influenced by personal characteristics. Future research should examine whether variation in food amount judgments is related to dieting behavior, disordered eating, or obesity.

Food patterns and dietary quality associated with organic food consumption during pregnancy; data from a large cohort of pregnant women in Norway

BACKGROUND

Little is known about the consumption of organic food during pregnancy. The aim of this study was to describe dietary characteristics associated with frequent consumption of organic food among pregnant women participating in the Norwegian Mother and Child Cohort Study (MoBa).

METHODS

The present study includes 63 808 women who during the years 2002-2007 answered two questionnaires, a general health questionnaire at gestational weeks 15 and a food frequency questionnaire at weeks 17-22. The exploration of food patterns by Principal component analyses (PCA) was followed by ANOVA analyses investigating how these food patterns as well as intake of selected food groups were associated with consumption of organic food.

RESULTS

The first principal component (PC1) identified by PCA, accounting for 12% of the variation, was interpreted as a 'health and sustainability component', with high positive loadings for vegetables, fruit and berries, cooking oil, whole grain bread and cereal products and negative loadings for meat, including processed meat, white bread, and cakes and sweets. Frequent consumption of organic food, which was reported among 9.1% of participants (n = 5786), was associated with increased scores on the 'health and sustainability component' (p < 0.001). The increase in score represented approximately 1/10 of the total variation and was independent of sociodemographic and lifestyle characteristics. Participants with frequent consumption of organic food had a diet with higher density of fiber and most nutrients such as folate, beta-carotene and vitamin C, and lower density of sodium compared to participants with no or low organic consumption.

CONCLUSION

The present study showed that pregnant Norwegian women reporting frequent consumption of organically produced food had dietary pattern and quality more in line with public advice for healthy and sustainable diets. A methodological implication is that the overall diet needs to be included in future studies of potential health outcomes related to consumption of organic food during pregnancy.

Diet, fitness and metabolic syndrome--the DR's EXTRA study

BACKGROUND AND AIMS

To study the independent and combined associations of diet and cardiorespiratory fitness with the prevalence of the metabolic syndrome (MetS).

METHODS AND RESULTS

We studied a population-based random sample of 663 men and 671 women 57-78 years of age at baseline of an ongoing randomised controlled trial. Based on a 4-day food record a diet score was created according to goals achieved (vegetables ≥400 g/day, fish ≥2 servings/week, fibre ≥14 g/1000 kcal, saturated fat <10 E%/day). Cardiorespiratory fitness was measured as maximal oxygen uptake (VO(2 max)) in a maximal symptom-limited bicycle ergometer test. MetS was defined by the National Cholesterol Education Program criteria. The lowest prevalence of MetS (5%) was observed among individuals in the highest VO(2 max) tertile and achieving 3-4 dietary goals. The highest prevalence (55%) was observed among those in the lowest VO(2 max) tertile and achieving none of the dietary goals. Among individuals in the highest VO(2 max) tertile, the odds ratio of having MetS was 0.04 (95% CI 0.02-0.10) for those achieving 3-4 dietary goals, 0.07 (0.04-0.14) for those achieving 1-2 dietary goals, and 0.16 (0.07-0.37) for those achieving none of the dietary goals compared with individuals in the lowest VO(2 max) tertile and achieving none of the goals after adjustment for confounding factors.

CONCLUSION

Healthy diet and higher levels of cardiorespiratory fitness are associated with a reduced risk of having MetS. However, fitness seems to have a stronger association with MetS than diet.

Comparisons of energy intake and energy expenditure in overweight and obese women with and without binge eating disorder

The purpose of this study was to determine whether there are differences in energy intake or energy expenditure that distinguish overweight/obese women with and without binge eating disorder (BED). Seventeen overweight/obese women with BED and 17 overweight/obese controls completed random 24-h dietary recall interviews, and had total daily energy expenditure (TDEE) assessed by the doubly labeled water (DLW) technique with concurrent food log data collection. Participants received two baseline dual-energy X-ray absorptiometry (DXA) scans and had basal metabolic rate (BMR) and thermic effect of food (TEF) measured using indirect calorimetry. Results indicated no between group differences in TDEE, BMR, and TEF. As in our previous work, according to dietary recall data, the BED group had significantly higher caloric intake on days when they had binge eating episodes than on days when they did not (3,255 vs. 2,343 kcal). There was no difference between BED nonbinge day intake and control group intake (2,233 vs. 2,140 kcal). Similar results were found for food log data. Dietary recall data indicated a trend toward higher average daily intake in the BED group (2,587 vs. 2,140 kcal). Furthermore, when comparing TDEE to dietary recall and food log data, both groups displayed significant under-reporting of caloric intake of similar magnitudes ranging from 20 to 33%. Predicted energy requirements estimated via the Harris-Benedict equation (HBE) underestimated measured TDEE by 23-24%. Our data suggest that increased energy intake reported by BED individuals is due to increased food consumption and not metabolic or under-reporting differences.

Energy intake and leukocyte telomere length in young adults

BACKGROUND

Dietary energy restriction in mammals, particularly at a young age, extends the life span. Leukocyte telomere length (LTL) is thought to be a bioindicator of aging in humans. High n-6 (omega-6) PUFA intake may accelerate LTL attrition.

OBJECTIVE

We determined whether lower energy and higher PUFA intakes in young adulthood are associated with shorter LTL in cross-sectional and longitudinal analyses.

DESIGN

In a longitudinal observational study (405 men, 204 women), diet was determined at baseline by a semiquantitative food-frequency questionnaire, and LTL was determined by Southern blots at mean ages of 30.1 y (baseline) and 43.2 y (follow-up). Spearman correlations and multivariable linear regression were used.

RESULTS

Baseline energy intake was inversely associated with follow-up LTL in men (standardized β = -0.171, P = 0.0005) but not in women (P = 0.039 for sex interaction). The difference in men between the highest and lowest quintiles of energy was 244 base pairs (bp) (95% CI: 59, 429 bp) and between extreme quintiles of LTL was 440 kcal (95% CI: 180, 700 kcal). Multivariable adjustment modestly attenuated the association (β = -0.157, P = 0.002). Inverse associations, which were noted for all macronutrients, were strongest for the unsaturated fatty acids. In multivariable models including energy and the macronutrients (as percentage of energy), the significant inverse energy-LTL association (but not the PUFA-LTL association) persisted. The energy-LTL association was restricted to never smokers (standardized β = -0.259, P = 0.0008; P = 0.050 for the smoking × calorie interaction).

CONCLUSIONS

The inverse calorie intake-LTL association is consistent with trial data showing beneficial effects of calorie restriction on aging biomarkers. Further exploration of energy intake and LTL dynamics in the young is needed.

Binge Eating Disorder Mediates Links between Symptoms of Depression, Anxiety, and Caloric Intake in Overweight and Obese Women

Despite considerable comorbidity between mood disorders, binge eating disorder (BED), and obesity, the underlying mechanisms remain unresolved. Therefore, the purpose of this study was to examine models by which internalizing behaviors of depression and anxiety influence food intake in overweight/obese women. Thirty-two women (15 BED, 17 controls) participated in a laboratory eating-episode and completed questionnaires assessing symptoms of anxiety and depression. Path analysis was used to test mediation and moderation models to determine the mechanisms by which internalizing symptoms influenced kilocalorie (kcal) intake. The BED group endorsed significantly more symptoms of depression (10.1 versus 4.8, P = 0.005 ) and anxiety (8.5 versus 2.7, P = 0.003). Linear regression indicated that BED diagnosis and internalizing symptoms accounted for 30% of the variance in kcal intake. Results from path analysis suggested that BED mediates the influence of internalizing symptoms on total kcal intake (empirical P < 0.001 ). The associations between internalizing symptoms and food intake are best described as operating indirectly through a BED diagnosis. This suggests that symptoms of depression and anxiety influence whether one engages in binge eating, which influences kcal intake. Greater understanding of the mechanisms underlying the associations between mood, binge eating, and food intake will facilitate the development of more effective prevention and treatment strategies for both BED and obesity.

Developments in obesity genetics in the era of genome-wide association studies

Obesity is an important factor contributing to the global burden of morbidity and mortality. By identifying obesity susceptibility genes, scientists aim to elucidate some of its aetiology. Early studies used candidate gene and genome-wide linkage approaches to search for such genes with limited success. However, the advent of genome-wide association studies (GWAS) has dramatically increased the pace of gene discovery. So far, GWAS have identified at least 50 loci robustly associated with body mass index (BMI), waist-to-hip ratio, body fat percentage and extreme obesity. Some of these have been shown to replicate in non-white populations and in children and adolescents. Furthermore, for some loci interaction studies have shown that the BMI-increasing effect is attenuated in physically active individuals. Despite many successful discoveries, the effect sizes of the established loci are small, and combined they explain only a fraction of the inter-individual variation in BMI. The low predictive value means that their value in mainstream health care is limited. However, as most of these newly established loci were not previously linked to obesity, they may provide new insights into body weight regulation. Continued efforts in gene discovery, using a range of approaches, will be needed to increase our understanding of obesity.

Insulin resistance in Chileans of European and indigenous descent: evidence for an ethnicity x environment interaction

Background

Effects of urbanisation on diabetes risk appear to be greater in indigenous populations worldwide than in populations of European origin, but the reasons are unclear. This cross-sectional study aimed to determine whether the effects of environment (Rural vs. Urban), adiposity, fitness and lifestyle variables on insulin resistance differed between individuals of indigenous Mapuche origin compared to those of European origin in Chile.

Methodology/Principal Findings

123 Rural Mapuche, 124 Urban Mapuche, 91 Rural European and 134 Urban European Chilean adults had blood taken for determination of HOMA-estimated insulin resistance (HOMA_IR) and underwent assessment of physical activity/sedentary behaviour (using accelerometry), cardiorespiratory fitness, dietary intake and body composition. General linear models were used to determine interactions with ethnicity for key variables. There was a significant “ethnicity x environment” interaction for HOMA_IR (Mean±SD; Rural Mapuche: 1.65±2.03, Urban Mapuche: 4.90±3.05, Rural European: 0.82±0.61, Urban European: 1.55±1.34, p_{(interaction)} = 0.0003), such that the effect of urbanisation on HOMA_IR was greater in Mapuches than Europeans. In addition, there were significant interactions (all p<0.004) with ethnicity for effects of adiposity, sedentary time and physical activity on HOMA_IR, with greater effects seen in Mapuches compared to Europeans, an observation that persisted after adjustment for potential confounders.

Conclusions/Significance

Urbanisation, adiposity, physical activity and sedentary behaviour influence insulin resistance to a greater extent in Chilean Mapuches than Chileans of European descent. These findings have implications for the design and implementation of lifestyle strategies to reduce metabolic risk in different ethnic groups, and for understanding of the mechanisms underpinning human insulin resistance.

Technology for behavioral assessment and intervention in bariatric surgery

Patients' behaviors have a substantial effect on postoperative outcomes after bariatric surgery. Thus, studying patients' behaviors is essential to learning how to optimize postoperative outcomes. To be most effective, this research should use the best tools available for assessing patient behavior. However, the traditional methods of behavioral assessment (e.g., questionnaires and clinical interviews) rely primarily on patients' retrospective self-report, which is often inaccurate. Despite their significant shortcomings, these types of assessments continue to predominate. However, technological advances now allow for much greater accuracy in the assessment of patient behaviors by way of devices, such as accelerometers and palmtop computers. Accelerometers allow for patients' physical activity to be measured objectively in great detail, in real-time, in the patients' natural environment. Ecologic momentary assessment using a palmtop computer or mobile telephone allows the assessment of important behaviors, such as eating and activity behaviors, to be measured, with many of the same advantages. Furthermore, new computer-assisted technologies are in development that will further facilitate behavioral assessment. Technology also has the potential to play an important role in the delivery of behavioral interventions aimed at bariatric surgery patients, given that Internet-based treatments have already proved effective for nonoperative weight loss and are often highly cost-effective and easily disseminable. Future research should evaluate the efficacy of these programs for bariatric patients.

Pharmacokinetics of alkylresorcinol metabolites in human urine

Wholegrain cereals are reported to promote beneficial health effects. Wholegrain wheat and rye are almost exclusive sources of alkylresorcinols, and intact alkylresorcinols together with their plasma and urinary metabolites, 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA) and 3,5-dihydroxybenzoic acid (DHBA), have been proposed as biomarkers of the intake of these foods in humans. The pharmacokinetics of alkylresorcinols and their metabolites in plasma have been determined but not that of the urinary metabolites. We aimed to characterise the urinary pharmacokinetics of alkylresorcinol metabolites in humans to evaluate their potential as biomarkers of wholegrain wheat and rye. A group of fifteen volunteers followed a low-alkylresorcinol diet for 2 d before ingesting a single dose of rye bread, containing 100 mg alkylresorcinols. Urine was collected between baseline (0 h) and 25 h after administration. Thereafter alkylresorcinol metabolites were quantified by HPLC with coulometric electrode array detection. Maximum excretion rates were observed at 5-6 h for both metabolites, DHPPA being predominant over DHBA and also possessing a greater area under the curve0-25 h. Total urinary recovery between 0 and 25 h yielded 43 % of ingested alkylresorcinols, and at 25 h significant amounts of metabolites were still retained in the body, suggesting that even a spot urine sample may be sufficient to indicate whether or not wholegrain wheat or rye is a daily dietary component. These results support the use of urinary DHPPA and DHBA as biomarkers of wholegrain wheat and rye and enable new potential for studying the association between wholegrain intake and diseases, even in the absence of dietary data.

Is maternal education level associated with diet in 10-year-old children?

OBJECTIVE

To examine the associations between maternal education level and diet in 10-year-old children.

DESIGN

Three-day diet diaries (child completed with parental help) were collected. Height and weight were measured in research clinics. Maternal education level was derived from a questionnaire completed during pregnancy and classified into low, medium or high. One-way ANOVA was undertaken to compare maternal education groups for nutrient intakes and the Kruskal-Wallis test used for food consumption.

SETTING

Avon Longitudinal Study of Parents and Children (ALSPAC), Bristol, UK.

SUBJECTS

Children (n 7474) who provided dietary data at age 10 years.

RESULTS

A large proportion (60 %) of the sample was classified as plausible reporters, with under-reporting accounting for 36 %. No clear differences were found for intakes of energy or macronutrients between maternal education groups for plausible reporters. However, there were marked differences in micronutrient intakes especially for vitamin C, retinol equivalents and folate, highlighting lower diet quality with lower maternal education level. Intakes of fruit and vegetables showed a positive gradient with increasing maternal education (57 % v. 79 % consumed fresh fruit in low and high educational groups, respectively). A trend towards higher intake in the lower educated group was shown for less healthy foods (meat pies P < 0·001; sausages, burgers and kebabs P < 0·001).

CONCLUSIONS

The quality of children's diet at 10 years was related to maternal education level. Lower maternal education was associated with less healthy food choices that could be detrimental to health. Further research is needed to establish if these associations can be explained by other socio-economic factors.

Health behaviors and racial disparity in blood pressure control in the national health and nutrition examination survey

Minorities have a higher prevalence of hypertension, a major risk factor for cardiovascular disease, which contributes to racial/ethnic disparities in morbidity and mortality in the United States. Many modifiable health behaviors have been associated with improved blood pressure control, but it is unclear how racial/ethnic differences in these behaviors are related to the observed disparities in blood pressure control. Cross-sectional analyses were conducted among 21 489 US adults aged >20 years participating in the National Health and Nutrition Examination Survey from 2001 to 2006. Secondary analyses were conducted among those with a self-reported diagnosis of hypertension. Blood pressure control was defined as systolic values <140 mm Hg and diastolic values <90 mm Hg (or <130 mm Hg and <80 mm Hg among diabetics, respectively). In primary analyses, non-Hispanic blacks had 90% higher odds of poorly controlled blood pressure compared with non-Hispanic whites after adjustment for sociodemographic and clinical characteristics (P<0.001). In secondary analyses among hypertensive subjects, non-Hispanic blacks and Mexican Americans had 40% higher odds of uncontrolled blood pressure compared with non-Hispanic whites after adjustment for sociodemographic and clinical characteristics (P<0.001). For both analyses, the racial/ethnic differences in blood pressure control persisted even after further adjustment for modifiable health behaviors, which included medication adherence in secondary analyses (P<0.001 for both analyses). Although population-level adoption of healthy behaviors may contribute to reduction of the societal burden of cardiovascular disease in general, these findings suggest that racial/ethnic differences in some health behaviors do not explain the disparities in hypertension prevalence and control.

The effect of eating frequency on appetite control and food intake: brief synopsis of controlled feeding studies

Increased eating frequency is postulated to increase metabolism, reduce hunger, improve glucose and insulin control, and reduce body weight, making it an enticing dietary strategy for weight loss and/or the maintenance of a healthy body weight. Because past research has primarily focused on the effects of eating frequency on changes in energy expenditure and body weight, limited data exist surrounding the impact of eating frequency on appetite control and energy intake. We provide a brief review of the controlled-feeding studies that primarily targeted the appetitive, hormonal, and food intake responses potentially altered with eating frequency. The 3 meal/d pattern served as the reference for defining increased or reduced eating frequency. In general, increased eating frequency led to lower peaks (P < 0.05) in perceived appetite, satiety, glucose, insulin, ghrelin, and PYY responses compared with reduced eating frequency. However, when examining these responses over the course of the day (i.e. using area under the curve assessments), no differences in any of these outcomes were observed. The rate of gastric emptying also appears to be unaltered with increased eating frequency. Subsequent food intake was examined in several studies with conflicting results. Regarding the effect of reduced eating frequency, several studies indicate significant increases in perceived appetite and reductions in perceived satiety when 1 or 2 meals were eliminated from the daily diet. Taken together, these findings suggest that increased eating frequency (>3 eating occasions/d) has minimal, if any, impact on appetite control and food intake, whereas reduced eating frequency(<3 eating occasions/d) negatively effects appetite control.

Relationship among alcohol intake, body fat, and physical activity: a population-based study

OBJECTIVES

Aside from fat, ethanol is the macronutrient with the greatest energy density. Whether the energy derived from ethanol affects body composition and fat mass is debatable. We investigated the relationship of alcohol intake, body composition, and physical activity in the U.S. population by using data from the Third National Health and Nutrition Examination Survey (NHANES III).

METHODS

A total of 10,550 subjects met eligibility criteria and constituted our study cohort. Estimated percent body fat and resting metabolic rate were calculated on the basis of the sum of the skinfolds. Multivariate regression analyses were performed accounting for the study sampling weight.

RESULTS

In both sexes, moderate and hazardous alcohol drinkers were younger (p < .05) and had significantly lower body mass index (p < 0.01) and body weight (p < 0.01) than non-drinkers. Those with hazardous alcohol consumption participated in significantly less physical activity compared with those with no alcohol use and moderate drinkers in both sexes. Women had significantly greater percent body fat than men. In multivariate linear regression analyses, the levels of alcohol consumption were found to be an independent predictor associated with lower percent body fat only in male subjects.

CONCLUSIONS

Our results showed that alcoholics are habitually less active and that alcohol drinking is an independent predictor of lower percent body fat, especially in male alcoholics.

Minimal changes in environmental temperature result in a significant increase in energy expenditure and changes in the hormonal homeostasis in healthy adults

OBJECTIVE

Resting energy expenditure (EE) is a major contributor to the total EE and thus plays an important role in body weight regulation. Adaptive thermogenesis is a major component of EE in rodents, but little is known on the effects of exposure of humans to mild and sustainable reduction in environmental temperature.

DESIGN

To characterize the dynamic changes in continuously measured resting EE, substrate utilization, and hormonal axes simultaneously in response to mild reduction in environmental temperature, we performed a cross-over intervention.

METHODS

Twenty-five volunteers underwent two 12-h recordings of EE in whole room indirect calorimeters at 24 and 19 °C with simultaneous measurement of spontaneous movements and hormonal axes.

RESULTS

Exposure to 19 °C resulted in an increase in plasma and urine norepinephrine levels (P<0.0001), and a 5.96% (P<0.001) increase in EE without significant changes in spontaneous physical activity. Exposure to the lower temperature resulted in a significant increase in free fatty acid levels (P<0.01), fasting insulin levels (P<0.05), and a marginal decrease in postprandial glucose levels. A small but significant (P<0.002) increase in serum free thyroxine and urinary free cortisol (P<0.05) was observed at 19 °C.

CONCLUSIONS

Our observations indicate that exposure to 19 °C, a mild and tolerable cold temperature, results in a predictable increase in EE driven by a sustained rise in catecholamine and the activation of counter-regulatory mechanisms.