Race-specific validation of food intake obtained from a comprehensive FFQ: the Adventist Health Study-2

Cause-specific and all-cause mortalities in vegetarian compared with those in nonvegetarian participants from the Adventist Health Study-2 cohort

BACKGROUND

There have been mixed results reported internationally when associating vegetarian dietary patterns with all-cause and cause-specific mortalities.

OBJECTIVES

This study aimed to extend our previous results by evaluating, with a larger number of deaths (N = 12,515), cause-specific mortalities comparing different vegetarian types with nonvegetarians.

METHODS

This prospective study used data from the Adventist Health Study-2 cohort. Mortality was ascertained between study baseline, 2002-2007, and follow-up through 2015. Dietary data were collected at baseline using a validated quantitative food frequency questionnaire and then categorized into 5 dietary patterns: nonvegetarian, semivegetarian, pescovegetarian, lacto-ovovegetarian, and vegan. Main outcomes and measures include all-cause and cause-specific mortalities using Cox proportional hazards regression models and competing risk methods.

RESULTS

The analytic sample included 88,400 participants who provided 971,424 person-years of follow-up. We report results pairwise as estimated at ages 65 and 85 y owing to age dependence of many hazard ratios (HRs). Compared with nonvegetarians, vegetarians had lower risks of mortality, overall (HR: 0.89; 95% confidence interval [CI]: 0.83, 0.95; HR: 0.98; 95% CI: 0.91, 1.04), from renal failure (HR: 0.52; 95% CI: 0.38, 0.70; HR: 0.65; 95% CI: 0.55, 0.76), infectious disease (HR: 0.57; 95% CI: 0.40, 0.82; HR: 0.90; 95% CI: 0.70, 1.17), diabetes (HR: 0.51; 95% CI: 0.33, 0.78; HR: 0.69; 95% CI: 0.53, 0.88), select cardiac (HR: 0.75; 95% CI: 0.65, 0.87; HR: 0.89; 95% CI: 0.83, 0.95), and ischemic heart disease causes (HR: 0.73; 95% CI: 0.59, 0.90; HR: 0.84; 95% CI: 0.75,0.94). Vegans, lacto-ovovegetarians, and pescovegetarians were also observed to have lower risks of total mortality and several similar cause-specific mortalities. However, higher cause-specified neurologic mortalities were observed among older vegetarians (estimated at age 85 y), specifically stroke (HR: 1.17; 95% CI: 1.02, 1.33), dementia (HR: 1.13; 95% CI: 1.00, 1.27), and Parkinson's disease (HR: 1.37; 95% CI: 0.98, 1.91). Results in Black subjects for vegetarian/nonvegetarian comparisons largely followed the same trends, but HRs were less precise owing to smaller numbers.

CONCLUSIONS

Vegetarian diets are associated with lower risk for all-cause and many cause-specific mortalities, especially among males and in younger subjects. However, higher risks are observed among older vegetarians for stroke and dementia. These results need further support and investigation.

Methods and participant characteristics in the Cancer Risk in Vegetarians Consortium: a cross-sectional analysis across 11 prospective studies

BACKGROUND

The associations of vegetarian diets with risks for site-specific cancers have not been estimated reliably due to the low number of vegetarians in previous studies. Therefore, the Cancer Risk in Vegetarians Consortium was established. The aim is to describe and compare the baseline characteristics between non-vegetarian and vegetarian diet groups and between the collaborating studies.

METHODS

We harmonised individual-level data from 11 prospective cohort studies from Western Europe, North America, South Asia and East Asia. Comparisons of food intakes, sociodemographic and lifestyle factors were made between diet groups and between cohorts using descriptive statistics.

RESULTS

2.3 million participants were included; 66% women and 34% men, with mean ages at recruitment of 57 (SD: 7.8) and 57 (8.6) years, respectively. There were 2.1 million meat eaters, 60,903 poultry eaters, 44,780 pescatarians, 81,165 vegetarians, and 14,167 vegans. Food intake differences between the diet groups varied across the cohorts; for example, fruit and vegetable intakes were generally higher in vegetarians than in meat eaters in all the cohorts except in China. BMI was generally lower in vegetarians, particularly vegans, except for the cohorts in India and China. In general, but with some exceptions, vegetarians were also more likely to be highly educated and physically active and less likely to smoke. In the available resurveys, stability of diet groups was high in all the cohorts except in China.

CONCLUSIONS

Food intakes and lifestyle factors of both non-vegetarians and vegetarians varied markedly across the individual cohorts, which may be due to differences in both culture and socioeconomic status, as well as differences in questionnaire design. Therefore, care is needed in the interpretation of the impacts of vegetarian diets on cancer risk.

Validity and Reproducibility of an Electronic Food Frequency Questionnaire in Argentinian Adults

This study aimed to validate a semiquantitative electronic food frequency questionnaire (eFFQ) in estimating the intake of a comprehensive list of nutrients and bioactive compounds among adults from six regions of Argentina using multiple 24 h dietary recall (24HR) as a reference. A total of 163 adults completed two administrations of the eFFQ and four 24HRs. The paired t-test/Wilcoxon signed-rank test, Spearman/Pearson correlations, cross-classification, weighted kappa statistics, and Bland-Altman plots were employed to determine relative validity. To determine reproducibility, intraclass correlations (ICC), cross-classification, and weighted kappa statistics were calculated. For relative validity, crude correlations ranged from 0.15 to 0.57; energy adjustment and de-attenuation slightly improved most of these correlations. In cross-classification analysis, agreements within one quintile adjacent to exact agreement (EA ± 1) ranged from 52.2% to ~74%; extreme misclassifications were < 7%. For reproducibility, the crude ICC ranged from 0.29 to 0.85, showing moderate to good correlations for most nutrients. Cross-classification analysis showed agreement levels for the EA ± 1 quintile of 70.6% to 87.7%. Weighted kappa values ranged from 0.21 to 0.62. The results show that this eFFQ is relatively valid in ranking adults according to their nutrient intake and has an acceptable reproducibility, yet it slightly overestimates the intake of most nutrients.

Systemic Lupus Erythematosus and the Ratio of Omega-3 to Omega-6 Fatty Acids Consumption among Women in the Adventist Health Study-2

OBJECTIVE

To assess the associations of omega-3 and omega-6 fatty acids consumption, and the ratio between the two, with self-reported doctor told Systemic Lupus Erythematosus (SLE) diagnosis. Further, to assess whether initiation of omega-3 supplements intake was related to time/year of SLE diagnosis.

METHODS

Data from 42,398 women in the Adventist Health Study-2 cohort were used for this cross-sectional study. Unconditional logistic regression modeling was used for all analyses with the following candidate covariates: age, race, education, smoking, and body mass index (BMI).

RESULTS

Compared to non-cases, participants with a diagnosis of SLE reported higher intakes of total omega-3 fatty acids and about the same intakes of omega-6 fatty acids. Overall, they had higher ratios of omega-3 to omega-6 fatty acids. When assessing odds ratios of SLE diagnosis by quartiles of omega-3 to omega-6 and DHA+EPA to omega-6, there was a positive significant trend (p trend = 0.005). Additionally, among those reporting intake of fish oil, 87% had initiated fish oil consumption around the time of SLE diagnosis. SLE was more likely to occur among Black women compared to White women, among ever smokers compared to never smokers, among overweight women compared to women with normal/underweight, and among women 50-59 years compared to those 30-49 year old. When a smaller 6 year follow-up study identified 64 incident SLE cases and assessed their omega-3 intake at baseline (6 years earlier and before the SLE diagnosis) their intake of omega-3 and fish oil was no different than among non-cases.

CONCLUSION

We observed a significant positive association between the ratio of omega-3 to omega-6 fatty acids consumption and prevalence of SLE. Among those with prevalent SLE, their year of starting supplementation of omega-3 and fish oil was closely linked to year of SLE diagnosis. Further, baseline intake of omega-3 fatty acids was not increased among 64 incident SLE cases identified during 6 years of follow-up. Our surprising finding can best be explained by reverse causation. This could be an example of how public health information is assimilated and acted upon by a health conscious public.

The benefit of vegetarian diets for reducing blood pressure in Taiwan: a historically prospective cohort study

OBJECTIVE

Past vegetarians research has often found that they have lower blood pressure (BP). Effects may include their lower BMI and higher intake levels of fruit and vegetables. Besides, the study pursues to extend this evidence in a diverse population containing vegans, lacto-ovo vegetarians and omnivores.

DESIGN

The study analyzed data on five hundred vigorous individuals aged 20 years or older from a standard medical screening program and provided validated questionnaire. Criteria were established for vegan, lacto-ovo vegetarian, partial vegetarian and omnivorous dietary patterns.

SETTING

Health screening programs were conducted at a standard medical screening program in Taiwan between 2006 and 2017. Dietary data were gathered by self-administered questionnaire.

SUBJECTS

Five hundred Taiwanese subjects representing the cohort.

RESULTS

Multiple regression analyses confirmed that the vegan vegetarians had lower systolic and diastolic BP (mmHg) than omnivorous Taiwanese (β =  - 6.8, p < 0.05 and β =  - 6.9, p < 0.001). Findings for lacto-ovo vegetarians (β =  - 9.1, p < 0.001 and β =  - 5.8, p < 0.001) were similar. The vegetarians were also less likely to be using antihypertensive medications. Defining hypertension as systolic BP > 139 mmHg or diastolic BP > 89 mmHg or routine of antihypertensive medications, the odds ratio of hypertension compared with omnivores was 0.37 (95% CI = 0.19-0.74), 0.57 (95% CI = 0.36-0.92) and 0.92 (95% CI = 0.50-1.70), respectively, for vegans, lacto-ovo vegetarians and partial vegetarians. Results were reduced after adjustment for BMI.

CONCLUSIONS

The study concludes from this relatively large study that vegetarians, especially vegans, with otherwise diverse characteristics but stable diets, do have lower systolic and diastolic BP and less hypertension than omnivores.

Dairy foods, calcium intakes, and risk of incident prostate cancer in Adventist Health Study-2

BACKGROUND

Prostate cancer is the most common noncutaneous cancer in American males. Causal links between dairy, or dietary calcium, and this cancer are considered suggestive but limited.

OBJECTIVES

To evaluate these associations in a large North American cohort, including many with no (or very low) dairy intake and much calcium from nondairy sources.

METHODS

A prospective cohort study of 28,737 Seventh-day Adventist men in the United States and Canada, of whom 6389 were of black ethnicity. Diet was measured by FFQ, and 275 male participants also provided repeated 24-h dietary recalls as a calibration substudy. Incident cancers were mainly found by matching with cancer registries. Analyses used multivariable proportional hazards regressions and regression calibration for some analyses.

RESULTS

In total, 1254 (190 advanced) incident prostate cancer cases were found during an average 7.8 y of follow-up. Men at the 90th percentile of dairy intake (430 g/d) compared with the 10th percentile (20.2 g/d) had higher prostate cancer risk (HR: 1.27; 95% CI: 1.12, 1.43). Similar findings, comparing the same g/d intakes, were demonstrated for advanced prostate cancers (HR: 1.38; 95% CI: 1.02, 1.88), for nonadvanced cases (HR: 1.27; 95% CI: 1.11, 1.45), in black participants (HR: 1.24; 95% CI: 0.98, 1.58), and when excluding vegan participants (HR: 1.22; 95% CI: 1.03, 1.43). Calibrated dairy (g/d) regressions (all participants and all prostate cancers), adjusting for dietary measurement error, found a HR of 1.75 (95% CI: 1.32, 2.32). Comparing 90th percentile intake to zero intakes (uncalibrated), the HR was 1.62 (95% CI: 1.26, 2.05). There was no evidence of an effect of higher (905 mg/d) compared with lower (349 mg/d) intakes of nondairy calcium (HR: 1.16; 95% CI: 0.94, 1.44).

CONCLUSIONS

Men with higher intake of dairy foods, but not nondairy calcium, had a higher risk of prostate cancer compared with men having lower intakes. Associations were nonlinear, suggesting greatest increases in risk at relatively low doses.

Ultra-processed food intake and animal-based food intake and mortality in the Adventist Health Study-2

BACKGROUND

Both ultra-processed foods and animal-derived foods have been associated with mortality in some studies.

OBJECTIVES

We aimed to examine the association of 2 dietary factors (ultra-processed foods and animal-based foods), adjusted for each other, with all-cause mortality.

METHODS

The setting is an observational prospective cohort study in North America, recruited from Seventh-day Adventist churches, comprised of 95,597 men and women, yielding an analytic sample of 77,437 participants after exclusions. The exposure of interest was diet measured by FFQ, in particular 2 dietary factors: 1) proportion of dietary energy from ultra-processed foods (other processing levels and specific substitutions in some models) and 2) proportion of dietary energy from animal-based foods (red meat, poultry, fish, and eggs/dairy separately in some models). The main outcome was all-cause mortality. Mortality data through 2015 were obtained from the National Death Index. Analyses used proportional hazards regression.

RESULTS

There were 9293 deaths. In mutually adjusted continuous linear models of both dietary factors (ultra-processed and animal-based foods), the HR for the 90th compared with the 10th percentile of the proportion of dietary energy from ultra-processed food was 1.14 (95% CI: 1.07, 1.21, comparing 47.7% with 12.1% dietary energy), whereas for animal-based food intake (meats, dairy, eggs) it was 1.01 (95% CI: 0.95, 1.07, comparing 25.0% with 0.4% dietary energy). There was no evidence of interaction (P = 0.36). Among animal-based foods, only red meat intake was associated with mortality (HR: 1.14; 95% CI: 1.08, 1.22, comparing 6.2% with 0% dietary energy).

CONCLUSIONS

Greater consumption of ultra-processed foods was associated with higher all-cause mortality in this health-conscious Adventist population with many vegetarians. The total of animal-based food consumption (meat, dairy, eggs) was not associated with mortality, but higher red meat intake was. These findings suggest that high consumption of ultra-processed foods may be an important indicator of mortality.

Reproducibility and validity of a food frequency questionnaire to assess cardiovascular health-related food intake among Mexican adolescents

There is a lack of region-adapted tools to evaluate diet as a risk factor for cardiovascular disease (CVD) in adolescents. The study aim was to evaluate the reproducibility and validity of a paper-based and region-adapted food frequency questionnaire (FFQ) designed to assess CVD-related food and nutrient intakes of adolescents from Northwest México. The study design was cross-sectional. The FFQ was developed in a two-step process: prototype designing and a pilot test, with re-tested in a 3-month period, along with two administrations of 24 h-recall (24 hR). Pearson's and intra-class correlation coefficients (PCC and ICC) were assessed. Bland-Altman plots, limits of agreement and quintile classifications were carried out. Participants (n 221) were 53·8 % male, 18·5 ± 0·4 years old. Reproducibility had a median PCC = 0·66 for processed meats, ranging from 0·40 (saturated fat) to 0·74 (fish & shellfish), P = 0·001. ICC ranged from 0·53 (saturated fat) to 0·80 (sodium; and nuts, seeds and legumes), P = 0·001. Validity comparing FFQ1 v. 24 hR mean, PCCs ranged from 0·12 (P = 0·06) to 0·95 (P = 0·001), and ICC from 0·20 (P = 0·048) to 0·88 (P = 0·001); comparing FFQ2 v. 24 hR mean, PCCs ranged from 0·07 (P = 0·25) to 0·46 (P = 0·001), and ICC from 0·15 (P = 0·106) to 0·58 (P = 0·001). The FFQ overestimated the intake of all food groups and nutrients (P < 0·05), while Cohen's κ showed coefficients lower than 0·20. The proposed FFQ represents a moderately validated tool to estimate CVD-related food and nutrient intakes as a risk factor, which can be used in combination with multiple administrations of 24 hRs, as a critical mean in future interventions intended to reduce cardiometabolic risk in adolescents.

Validity of FFQ Estimates of Total Sugars, Added Sugars, Sucrose and Fructose Compared to Repeated 24-h Recalls in Adventist Health Study-2 Participants

Sugar intake is a potentially important aspect of diet which has not previously been validated in the Adventist Health Study-2 (AHS-2). We sought to validate the food frequency questionnaire (FFQ) measurement of total sugars, added sugars, sucrose, and fructose against multiple 24-h dietary recalls (recalls) in AHS-2 participants. Food consumption data from a self-administered FFQ and six recalls from 904 participants were combined with nutrient profile data to estimate daily sugar intake. Validity was evaluated among all participants and by race. FFQ and recall means were compared and correlation coefficients (Spearman’s, energy-adjusted log-transformed Pearson’s, deattenuated Pearson’s) were calculated. Mean total energy, total sugars, and fructose intake were higher in the FFQ, whereas added sugars and sucrose were higher in recalls. The energy-adjusted (log-transformed) deattenuated correlations among all participants were: total sugars (r = 0.42, 95% CI 0.32–0.52), added sugars (r = 0.50, 95% CI 0.36–0.59), sucrose (r = 0.32, 95% CI 0.23–0.42), and fructose (r = 0.50, 95% CI 0.40–0.59). We observed moderate validity for added sugars and fructose and low-moderate validity for total sugars and sucrose measured by the AHS-2 FFQ in this population. Dietary sugar estimates from this FFQ may be useful in assessing possible associations of sugars intake with health outcomes.

Egg intake moderates the rate of memory decline in healthy older adults

Eggs contain important compounds related to enhanced cognition, but it is not clear if egg consumption, as a whole, has a direct impact on memory decline in older adults. This study aimed to determine whether egg intake levels predict the rate of memory decline in healthy older adults after sociodemographic and dietary controls. We conducted a secondary analysis of data from 470 participants, age 50 and over, from the Biospsychosocial Religion and Health Study. Participants completed a food frequency questionnaire, which was used to calculate egg intake and divide participants into Low (<23 g/week, about half an egg), Intermediate (24-63 g/week, half to 1½ eggs) and High (≥63 g/week, about two or more eggs) tertiles. Participants were administered the California Verbal Learning Test - 2nd Edition (CVLT-II) Short Form in 2006-2007, and 294 of them were again tested in 2010-2011. Using linear mixed model analysis, no significant cross-sectional differences were observed in CVLT-II performance between egg intake levels after controlling for age, sex, race, education, body mass index, cardiovascular risk, depression and intake of meat, fish, dairy and fruits/vegetables. Longitudinally, the Intermediate egg group exhibited significantly slower rates of decline on the CVLT-II compared to the Low egg group. The High egg group also exhibited slower rates of decline, but not statistically significant. Thus, limited consumption of eggs (about 1 egg/week) was associated with slower memory decline in late life compared to consuming little to no eggs, but a dose-response effect was not clearly evident. This study may help explain discrepancies in previous research that did not control for other dietary intakes and risk factors.

Vegetarian Dietary Patterns and Cognitive Function among Older Adults: The Adventist Health Study-2

We explored effects on cognitive function of following plant-based vegetarian compared with non-vegetarian dietary patterns in otherwise healthy older community-dwelling members of the Adventist Health Study-2 cohort (n = 132). Cognition was assessed using a comprehensive neuropsychological battery; a principal components analysis derived processing speed, executive function, and memory/language factors. Mild memory impairment (MMI) (n = 26, 19.7%) was identified by memory tests. Vegetarians consumed (a) meats, fish, and dairy <1 time/month, (b) dairy ≥1 time/month and meats, and fish <1 time/month, or (c) fish ≥1 time/month, no limits on dairy, and meats <1 time/month. Dietary patterns were determined at baseline, for each decade, and at cognitive assessment; a diet stability score was calculated. Factor scores were not different between vegetarians and non-vegetarians, nor was dietary pattern associated with a lower odds of MMI. A more stable diet over the life course was associated with better memory/language [β = 0.021 SE(β) = 0.008; p = 0.01]. This exploratory study did not support differences in processing speed, executive function, or memory/language abilities between vegetarians and non-vegetarians but did suggest that a more stable dietary pattern which was characteristic of vegetarians was associated with better memory/language abilities.

Dietary patterns and hip fracture in the Adventist Health Study 2: combined vitamin D and calcium supplementation mitigate increased hip fracture risk among vegans

BACKGROUND

Concerns regarding the adequacy of vegetarian diets with respect to fracture risk continue.

OBJECTIVES

We aimed to explore the influence of 5 previously defined dietary patterns on hip fracture risk and whether this association is modified by concomitant calcium and vitamin D supplementation.

METHODS

The Adventist Health Study 2 is a prospective cohort study in which participants were enrolled during 2002-2007; proportional hazards regression analyses were used to estimate fracture risk. Participants reside throughout the United States and Canada. A total of 34,542 non-Hispanic white peri- and postmenopausal women and men 45 y and older responded to the biennial hospital history form and were followed for a median of 8.4 y.

RESULTS

The study identified 679 incident hip fractures during 249,186 person-years of follow-up. Fracture risk varied according to dietary pattern, with a clear effect modification by concurrent supplementation with both vitamin D and calcium. In multivariable models, including adjustment for calcium and vitamin D supplementation, female vegans had 55% higher risk of hip fracture (HR: 1.55; 95% CI: 1.06, 2.26) than nonvegetarians (NVEGs), whereas there was no association between diet pattern and hip fracture risk in men. When further stratifying females on supplement use with both vitamin D and calcium, vegans taking both supplements were at no greater risk of hip fracture than the subjects with other dietary patterns including the NVEGs.

CONCLUSIONS

Without combined supplementation of both vitamin D and calcium, female vegans are at high risk of hip fracture. However, with supplementation the excessive risk associated with vegans disappeared. Further research is needed to confirm the adequacy of a vegan diet supplemented with calcium and vitamin D with respect to risk of fracture.

Dairy, soy, and risk of breast cancer: those confounded milks

BACKGROUND

Associations between soy, dairy intakes and breast cancer risk are inconsistent. No studies exist with large numbers of dairy consumers and soy consumers to assess mutual confounding.

METHODS

The study cohort contains 52 795 North American women, initially free of cancer, followed for 7.9 years (29.7% were Black). Dietary intakes were estimated from food frequency questionnaires and, for 1011 calibration study subjects, from six structured 24-h dietary recalls. Incident invasive breast cancers were detected mainly by matching with cancer registries. Analyses used multivariable proportional hazards regression.

RESULTS

The participants (mean age of 57.1 years) experienced 1057 new breast cancer cases during follow-up. No clear associations were found between soy products and breast cancer, independently of dairy. However, higher intakes of dairy calories and dairy milk were associated with hazard ratios (HRs) of 1.22 [95% confidence interval (CI): 1.05-1.40] and 1.50 (95% CI 1.22-1.84), respectively, comparing 90th to 10th percentiles of intakes. Full fat and reduced fat milks produced similar results. No important associations were noted with cheese and yogurt. Substituting median intakes of dairy milk users by those of soy milk consumers was associated with HR of 0.68 (95% CI: 0.55-0.85). Similar-sized associations were found among pre- and post-menopausal cases, with CIs also excluding the null in estrogen receptor (ER+, ER-), and progesterone receptor (PR+) cancers. Less biased calibrated measurement-error adjusted regressions demonstrated yet stronger, but less precise, HRs and CIs that still excluded the null.

CONCLUSIONS

Higher intakes of dairy milk were associated with greater risk of breast cancer, when adjusted for soy intake. Current guidelines for dairy milk consumption could be viewed with some caution.

Validation of estimated glycaemic index and glycaemic load, stratified by race, in the Adventist Health Study-2 (AHS-2)

OBJECTIVE

Few studies have validated FFQ estimates of dietary glycaemic index (GI) and load (GL). We investigated how well our estimates of overall GI and GL from FFQs correlate with estimates from repeated 24 h recall data to validate overall GI and GL in the Adventist Health Study-2 (AHS-2).

DESIGN

The AHS-2 is a prospective population-based cohort of 95 873 Seventh-day Adventist adult church members enrolled from 2002 to 2007 to investigate diet, cancer and mortality.

SETTING

A 204-item FFQ was used to assess race- and gender-specific validity of GI and GL and 24 h recall data, from the calibration sub-study, were used as the reference.

PARTICIPANTS

The 734 calibration study participants were randomly selected by church and included approximately equal numbers of blacks and whites but were otherwise similar to the whole cohort with respect to gender, age, education and vegetarian status.

RESULTS

The deattenuated correlation coefficients for overall GI ranged from 0·19 (95 % CI -0·06, 0·53) in black men to 0·46 (95 % CI 0·40, 0·60) in black women, with both non-black men and women falling between those values (0·45 (95 % CI 0·35, 0·65) and 0·38 (95 % CI 0·27, 0·57), respectively). GL correlations were somewhat higher for all study participants. When looking at the entire cohort, the deattenuated validity correlation value for overall GI was (r 0·38, 95 % CI 0·36, 0·47) and GL was (r 0·39, 95 % CI 0·34, 0·49).

CONCLUSIONS

Our findings support the cautious use of our FFQ in epidemiological studies when assessing associations of overall GI and GL with disease risk. However, observed differences by race should be considered when interpreting results.

Assessment of polyunsaturated fatty acids: A self-report and biomarker assessment with a racially and ethnically diverse sample of women

Polyunsaturated fatty acids (PUFAs) play an important role in human health, influencing chronic disease and mortality. Food Frequency Questionnaires (FFQs) are widely used to assess self-reported diet, but they can be subject to a variety of errors. Accordingly, an accurate assessment of diet is crucial in nutrition research. This study examined the association between a widely-used self-report measure of PUFAs (Diet History Questionnaire-II: DHQ-II) with the proportion of PUFA in red blood cell (RBC) membranes, and examined whether this relationship was moderated by race/ethnicity. In a racially and ethnically diverse sample of 132 female participants (M_age = 21.97±3.98, range 18 to 42 years), bivariate correlations and linear regression analyses demonstrated associations between DHQ-II and proportion of nutrients in RBCs for omega-3 fatty acids EPA (r = 0.39, ß = 0.38, p < .01), DHA (r = 0.48, ß = 0.47, p < .01), and EPA+DHA (r = 0.51, β = 0.49, p < .01). No associations were found for omega-3 fatty acid ALA or omega-6 fatty acids LA or ARA. DHQ-II and RBC associations for EPA, DHA, and EPA+DHA were moderated by race/ethnicity, controlling for age. Self-report of EPA was most consistent with RBC proportions for Caucasian individuals, and less consistent for Black/African American individuals. Self-reports of DHA and EPA+DHA were most consistent with RBC proportions for Caucasian individuals, and less consistent for Black/African American individuals and Hispanic/Latina individuals, although still statistically significant. No associations were detected for Hispanic/Latina individuals (for EPA only), Asian/Pacific Islanders or individuals of mixed/other descent. The present study found that when compared to PUFA biomarkers, the DHQ-II did not assess PUFAs consistently across all racial/ethnic groups in this sample of women. Further research is needed to determine what factors contribute to weak or lacking correlations between reported fat intake and corresponding values in RBCs, including but not limited to recall errors, underestimations of fatty acids in food composition databases, insufficient DHQ-II assessment of fatty acids in general and from particular cultures, and genetic differences in fat metabolism.

A Vegetarian-Style Dietary Pattern Is Associated with Lower Energy, Saturated Fat, and Sodium Intakes; and Higher Whole Grains, Legumes, Nuts, and Soy Intakes by Adults: National Health and Nutrition Examination Surveys 2013-2016

Consumer demand for plant-based foods is increasing though the reasons may vary. Plant foods are sole sources of dietary fiber, vitamin C, and flavonoids and good sources of vitamin B1, folic acid, potassium, and magnesium. They are low in saturated fat, and do not contain cholesterol and vitamin B12. Plant foods are associated with better body weight and healthy blood lipid profile. This cross-sectional study used nationally representative National Health and Nutrition Examination Survey 2013-2016 data and compared nutrient and food pattern food group intakes of adults eating a vegetarian-style diet with adults eating a nonvegetarian diet. Adults 20+ years (N = 10,064) were grouped using the Dietary Guidelines for Americans 2015-2020 definition of vegetarian-style diet, which is modelled as lacto-ovo-vegetarian diet. Trained dietary interviewers collected self-reported dietary intake data using a 24-h recall and an automated multi-pass method. Means were compared using linear contrasts (p < 0.01). On average, the vegetarians ate an estimated 419 fewer kilocalories, 7 g less saturated fat, and 1274 mg less sodium. The vegetarian-style diet was higher in micronutrient density, except for vitamin B12 and zinc. The vegetarians ate more whole grains, legumes, nuts, and soy products. Fruit, vegetables, and dairy intakes were similar for both groups. A vegetarian-style diet may be advocated to control energy, saturated fat, and sodium intakes.

The American Cancer Society Cancer Prevention Study-3 FFQ Has Reasonable Validity and Reproducibility for Food Groups and a Diet Quality Score

BACKGROUND

FFQs are commonly used to assess dietary intake and it is important to evaluate their performance in the target population.

OBJECTIVE

We evaluated the reproducibility and relative validity of the Cancer Prevention Study-3 (CPS-3) FFQ in estimating usual intake of 63 food groups and diet quality in accordance with the American Cancer Society dietary guidelines for cancer prevention.

METHODS

A subset of participants from the CPS-3 (433 women, 244 men), 31-70 y of age, were included in a cross-sectional diet assessment substudy (2015-2016). Reproducibility was assessed by comparing estimates from repeat FFQs, approximately 1 y apart, using Spearman correlation coefficient (rs) and Pearson correlation coefficient (rp) correlations for food groups and diet quality, respectively. Validity was assessed similarly by comparing FFQ estimates with estimates from ≤6 interviewer-administered 24-h dietary recall (24HR). Analyses were stratified by sex and race/ethnicity.

RESULTS

Reproducibility correlations for repeated FFQs were > 0.50 for 83-97% of food groups analyzed across strata of sex and race. Although participants tended to overreport plant foods (e.g., fruits and legumes) and underreport refined grains and sugar-sweetened beverages, the median energy-adjusted, deattenuated Spearman correlations comparing the second FFQ to the 24HR were 0.50 and 0.52 among men and women (range: 0.05-0.82), respectively, suggesting that ranking was preserved for most food groups. Validity was highest for coffee, alcohol, and total dairy, and lowest for pasta and regular-fat yogurt. Median validity across food groups varied by race/ethnicity and was highest among whites (rs = 0.54) followed by Hispanics (rs = 0.49) and African Americans (rs = 0.45). The diet quality score had good validity in all subgroups examined, but was higher among men (rp = 0.69) than women (rp = 0.61), and lower among whites (rp = 0.62) than Hispanics (rp = 0.64) or African Americans (rp = 0.73).

CONCLUSIONS

This study indicates good reproducibility and validity of the CPS-3 FFQ for most major food groups and the diet quality score in all sex and race/ethnicity groups examined.

Tomato consumption and intake of lycopene as predictors of the incidence of prostate cancer: the Adventist Health Study-2

PURPOSE

Studies have controversially suggested that prostate cancer, the most common cancer among Western men, is less common among those with a high intake of tomato products and lycopene. We examine multivariable associations between the intake of tomatoes and lycopene, and risk of prostate cancer.

METHODS

In a prospective study of 27,934 Adventist men without prevalent cancer, Cox proportional hazard regression analyses were used to address the objectives. Dietary measurement error was partially corrected with regression calibration.

RESULTS

1226 incident cases of prostate cancer, 355 of them aggressive, were identified during 7.9 years of follow-up. Consumption of canned and cooked tomatoes more than four times a week was associated with a HR = 0.72 (95% CI 0.55, 0.94, P = 0.02) comparing to risk in those never consuming this food. Treating this as a continuous variable, adjusting for confounders, produces a similar result, HR = 0.86 (95% CI 0.75, 0.99), comparing 64 g/day with zero intakes (questionnaire data). Regression calibration, although less precise, suggests a yet stronger and statistically significant inverse relationship, comparing a 24-h dietary recall intake of 71 g/day canned and cooked tomato product, with zero intake. Uncalibrated multivariable-adjusted competing risk analyses do not find differences in tomato associations between aggressive and non-aggressive prostate cancers although power for aggressive cancers is limited.

CONCLUSION

Consumption of canned and cooked tomatoes may reduce the risk of prostate cancer. These products contain more available lycopene. However, an observational study cannot exclude confounding by some unidentified, prostate cancer preventive factor. Clinical Trial Registry: ClinicalTrials.gov Identifier: NCT03615599.

Adverse childhood experiences and depressive symptoms: Protective effects of dietary flavonoids

OBJECTIVES

Adverse childhood experiences (ACEs) are associated with increased inflammation, stress, and depression. Diet patterns rich in flavonoids may buffer the effects of ACEs on depression through neuroprotective mechanisms. No studies have examined the protective effects of dietary flavonoids on depressive symptoms after ACEs. We examine the relationships among ACEs, perceived stress, depressive symptoms, and flavonoid intake in older adults.

METHODS

In this longitudinal cohort study, flavonoid intake was provided by 6404 Seventh-day Adventist adults in North America who, as part of the Adventist Health Study-2, completed a validated food frequency questionnaire in 2002-6. ACEs, perceived stress, and depressive symptoms were assessed in the Biopsychosocial Religion and Health Study in 2006-7 and 2010-11. Bootstrapping models predicting depression were tested after controls.

RESULTS

ACEs were associated with adult depressive symptoms and perceived stress mediated this relationship. A moderated mediation model indicates that flavonoid intake buffers the association between perceived stress and depressive symptoms after ACEs. Flavonoid consumption was negatively associated with depressive symptoms (β = -0.034, p = .03). As ACEs increased by one standard deviation, depressive symptoms increased through the interaction of perceived stress and flavonoids when flavonoids were consumed a standard deviation below the mean (effect = 0.040 SD, BC 95% CI [0.030, 0.052]). Depressive symptoms were lower for those that consumed flavonoids a standard deviation above the mean (effect =. 035 SD, BC 95% CI [0.025, 0.046]).

CONCLUSION

A varied diet rich in flavonoids may reduce depressive symptoms associated with perceived stress following ACEs exposure.

Observed Physical Function Is Associated With Better Cognition Among Elderly Adults: The Adventist Health Study-2

Lifestyle factors may individually protect against the development of mild cognitive impairment. We investigate the relationships between both self-reported physical activity and measured physical function with cognition in a population of elderly adults, more than half of whom follow vegetarian dietary patterns. Otherwise healthy adults (n = 127, mean age 74.9 ± 7.9 years, 61.3% current vegetarians) were assessed using a comprehensive neuropsychological battery. A principal components analysis derived processing speed, executive function, and memory/language factors. Participants reported current levels of vigorous physical activity on questionnaires, and physical function and mobility were measured with the Physical Performance Test (PPT) and Timed Up and Go (TUG) Test. Generalized linear models estimated β coefficients for cross-sectional associations between cognitive factors and indicators of physical abilities and self-reported physical activity. Better physical function indicated by PPT was associated with higher scores on the processing speed factor (β = 0.21 SDs for each 4.4-point increase in PPT score; p = 0.02). Faster TUG times were also associated with higher processing speed factor scores (β = 0.21 SDs increase for each 2.8 second less TUG time; p = 0.02). Self-reported levels of vigorous physical activity were not associated with any area of cognitive function; the association between PPT, TUG and processing speed was independent of physical activity. Associations between PPT and TUG and processing speed were stronger among participants who followed vegetarian dietary patterns. Better physical function may have an effect on cognition in a context of healthy lifestyles.

Vegetarian Epidemiology: Review and Discussion of Findings from Geographically Diverse Cohorts

Epidemiologic cohort studies enrolling a large percentage of vegetarians have been highly informative regarding the nutritional adequacy and possible health effects of vegetarian diets. The 2 largest such cohorts are the European Prospective Investigation into Cancer and Nutrition-Oxford (EPIC-Oxford) and the Adventist Health Study-2 (AHS-2). These cohorts are described and their findings discussed, including a discussion of where findings appear to diverge. Although such studies from North America and the United Kingdom have been important, the large majority of the world's vegetarians live in other regions, particularly in Asia. Findings from recent cohort studies of vegetarians in East and South Asia are reviewed, particularly the Tzu Chi Health Study and Indian Migration Study. Important considerations for the study of the health of vegetarians in Asia are discussed. Vegetarian diets vary substantially, as may associated health outcomes. Cohort studies remain an important tool to better characterize the health of vegetarian populations around the globe.

Patterns of amino acid intake are strongly associated with cardiovascular mortality, independently of the sources of protein

Background

The intake of specific amino acids (AA) has been associated with cardiovascular health, but amino acids are consumed together as dietary protein. Here we investigated the association between identified patterns of amino acid intake and cardiovascular mortality.

Methods

A total of 2216 cardiovascular deaths among 79 838 men and women from the Adventist Health Study-2 were included in our analysis. Baseline dietary patterns based on the participants' amino acids intakes were derived by factor analysis. Using Cox regression analyses, we estimated multivariate-adjusted hazard ratios (HRs) adjusted for sociodemographic and lifestyle factors and other dietary components.

Results

Three patterns of amino acids were identified. Factor 1 was positively associated with cardiovascular disease (CVD) mortality [hazard ratio (HR)Q5-Q1: 1.62, 98.75% confidence interval (CI): 1.15, 2.28; P-trend &lt;0.001]; and Factors 2 and 3 were inversely associated with CVD mortality (HR Q5-Q1 Factor 2: 0.74, 98.75% CI: 0.53, 1.04; P-trend &lt;0.01 and HR Q5-Q1 Factor 3: 0.65, 98.75% CI: 0.44, 0.95; P-trend &lt;0.05]. The associations with Factor 1 (with high loadings on indispensable amino acids such as branched chain amino acids, lysine, methionine) and Factor 3 (with high loadings on non-indispensable amino acids, namely arginine, glycine, aspartate+asparagine) remained significant after further adjustment for nutrient intake and for the five protein source patterns identified previously (HR Q5-Q1: 1.56 (0.99, 2.45) and 0.55 (0.35, 0.85); P-trends &lt; 0.01).

Conclusions

Indispensable AA have a positive and some non-indispensable AA have a negative, independent, strong association with the risk of cardiovascular mortality.

Patterns of plant and animal protein intake are strongly associated with cardiovascular mortality: the Adventist Health Study-2 cohort

Background

Current evidence suggests that plant and animal proteins are intimately associated with specific large nutrient clusters that may explain part of their complex relation with cardiovascular health. We aimed at evaluating the association between specific patterns of protein intake with cardiovascular mortality.

Methods

We selected 81 337 men and women from the Adventist Health Study-2. Diet was assessed between 2002 and 2007, by using a validated food frequency questionnaire. Dietary patterns based on the participants' protein consumption were derived by factor analysis. Cox regression analysis was used to estimate multivariate-adjusted hazard ratios (HRs) adjusted for sociodemographic and lifestyle factors and dietary components.

Results

There were 2276 cardiovascular deaths during a mean follow-up time of 9.4 years. The HRs for cardiovascular mortality were 1.61 [98.75% confidence interval (CI), 1.12 2.32; P-trend < 0.001] for the 'Meat' protein factor and 0.60 (98.75% CI, 0.42 0.86; P-trend < 0.001) for the 'Nuts & Seeds' protein factor (highest vs lowest quintile of factor scores). No significant associations were found for the 'Grains', 'Processed Foods' and 'Legumes, Fruits & Vegetables' protein factors. Additional adjustments for the participants' vegetarian dietary pattern and nutrients related to cardiovascular disease outcomes did not change the results.

Conclusions

Associations between the 'Meat' and 'Nuts & Seeds' protein factors and cardiovascular outcomes were strong and could not be ascribed to other associated nutrients considered to be important for cardiovascular health. Healthy diets can be advocated based on protein sources, preferring low contributions of protein from meat and higher intakes of plant protein from nuts and seeds.

Plant-Based Diets Are Associated With Lower Adiposity Levels Among Hispanic/Latino Adults in the Adventist Multi-Ethnic Nutrition (AMEN) Study

Background: The Hispanic/Latino population in the US is experiencing high rates of obesity and cardio-metabolic disease that may be attributable to a nutrition transition away from traditional diets emphasizing whole plant foods. In the US, plant-based diets have been shown to be effective in preventing and controlling obesity and cardio-metabolic disease in large samples of primarily non-Hispanic subjects. Studying this association in US Hispanic/Latinos could inform culturally tailored interventions.

Objective: To examine whether the plant-based diet pattern that is frequently followed by Hispanic/Latino Seventh-day Adventists is associated with lower levels of adiposity and adiposity-related biomarkers.

Methods: The Adventist Multiethnic Nutrition Study (AMEN) enrolled 74 Seventh-day Adventists from five Hispanic/Latino churches within a 20 mile radius of Loma Linda, CA into a cross-sectional study of diet (24 h recalls, surveys) and health (anthropometrics and biomarkers).

Results: Vegetarian diet patterns (Vegan, Lacto-ovo vegetarian, Pesco-vegetarian) were associated with significantly lower BMI (24.5 kg/m² vs. 27.9 kg/m², p = 0.006), waist circumference (34.8 in vs. 37.5 in, p = 0.01), and fat mass (18.3 kg vs. 23.9 kg, p = 0.007), as compared to non-vegetarians. Adiposity was positively associated with pro-inflammatory cytokines (Interleukin-6) in this sample, but adjusting for this effect did not alter the associations with vegetarian diet.

Conclusions: Plant-based eating as practiced by US-based Hispanic/Latino Seventh-day Adventists is associated with BMI in the recommended range. Further work is needed to characterize this type of diet for use in obesity-related interventions among Hispanic/Latinos in the US.

Avocado Intake, and Longitudinal Weight and Body Mass Index Changes in an Adult Cohort

Avocados contain nutrients and bioactive compounds that may help reduce the risk of becoming overweight/obese. We prospectively examined the effect of habitual avocado intake on changes in weight and body mass index (BMI). In the Adventist Health Study (AHS-2), a longitudinal cohort (~55,407; mean age ~56 years; U.S. and Canada), avocado intake (standard serving size 32 g/day) was assessed by a food frequency questionnaire (FFQ). Self-reported height and weight were collected at baseline. Self-reported follow-up weight was collected with follow-up questionnaires between four and 11 years after baseline. Using the generalized least squares (GLS) approach, we analyzed repeated measures of weight in relation to avocado intake. Marginal logistic regression analyses were used to calculate the odds of becoming overweight/obese, comparing low (>0 to <32 g/day) and high (≥32 g/day) avocado intake to non-consumers (reference). Avocado consumers who were normal weight at baseline, gained significantly less weight than non-consumers. The odds (OR (95% CI)) of becoming overweight/obese between baseline and follow-up was 0.93 (0.85, 1.01), and 0.85 (0.60, 1.19) for low and high avocado consumers, respectively. Habitual consumption of avocados may reduce adult weight gain, but odds of overweight/obesity are attenuated by differences in initial BMI values.

Comparison of phytosterol intake from FFQ with repeated 24-h dietary recalls of the Adventist Health Study-2 calibration sub-study

We evaluated the performance of an FFQ in estimating phytosterol intake against multiple 24-h dietary recalls (24HDR) using data from 1011 participants of the calibration sub-study of the Adventist Health Study-2 (AHS-2) cohort. Dietary assessments of phytosterol intake included a self-administered FFQ and six 24HDR and plasma sterols. Plasma sterols were determined using the GLC flame ionisation method. Validation of energy-adjusted phytosterol intake from the FFQ with 24HDR was conducted by calculating crude, unadjusted, partial and de-attenuated correlation coefficients (r) and cross-classification by race. On average, total phytosterol intake from the FFQ was 439·6 mg/d in blacks and 417·9 mg/d in whites. From the 24HDR, these were 295·6 mg/d in blacks and 351·4 mg/d in whites. Intake estimates of β-sitosterol, stigmasterol, other plant sterols and total phytosterols from the FFQ had moderate to strong correlations with estimates from 24HDR (r 0·41-0·73). Correlations were slightly higher in whites (r 0·42-0·73) than in blacks (r 0·41-0·67). FFQ estimates were poorly correlated with plasma sterols as well as 24HDR v. plasma sterols. We conclude that the AHS-2 FFQ provided reasonable estimates of phytosterol intake and may be used in future studies relating phytosterol intake and disease outcomes.

Red and Processed Meat and Mortality in a Low Meat Intake Population

Associations of low-to-moderate consumption of red and processed meat with mortality would add to the evidence of possible adverse effects of these common foods. This study aims to investigate the association of red and processed meat intake with mortality. The Adventist Health Study-2 (AHS-2) is a prospective cohort study of ~96,000 Seventh-day Adventist men and women recruited in the US and Canada between 2002 and 2007. The final analytic sample after exclusions was 72,149. Cox proportional hazards regression was used and hazard ratios (HR) and confidence intervals (CI) were obtained. Diet was assessed by a validated quantitative food frequency questionnaire (FFQ), calibrated using six 24-h dietary recalls. Mortality outcome data were obtained from the National Death Index. During a mean follow-up of 11.8 years, there were 7961 total deaths, of which 2598 were Cardiovascular diseases (CVD) deaths and 1873 were cancer deaths. Unprocessed red meat was associated with risk of all-cause mortality (HR: 1.18; 95% CI: 1.07–1.31) and CVD mortality (HR: 1.26; 95% CI: 1.05–1.50). Processed meat alone was not significantly associated with risk of mortality. The combined intake of red and processed meat was associated with all-cause mortality (HR: 1.23; 95% CI: 1.11–1.36) and CVD mortality (HR: 1.34; 95% CI: 1.12–1.60). These findings suggest moderately higher risks of all-cause and CVD mortality associated with red and processed meat in a low meat intake population.

Plant-Based Diets in Hispanic/Latino Adult Adventists in the United States and Their Association With Body Mass Index

PURPOSE

To characterize plant-based dietary practices and examine their relationship with body mass index (BMI) in Hispanic/Latino Seventh-day Adventists (SDA).

DESIGN

Cross-sectional analyses of data among Hispanics/Latinos in the Adventist Health Study-2 (AHS-2).

SETTING

The AHS-2 is a cohort of SDA adults (n = 96 592) in North America.

PARTICIPANTS

A total of 3475 Hispanics/Latinos who provided demographic, dietary, anthropometric, and lifestyle data at enrollment.

MEASURES

Plant-based dietary practices were determined from food frequency questionnaire; BMI, demographic, and lifestyle data were assessed by questionnaire.

ANALYSIS

In linear regression analysis, plant-based diets were modeled as dummy variables with nonvegetarian as the referent group and log(BMI) as the outcome adjusted for age, sex, education, exercise, nativity, alcohol use, smoking, and energy intake.

RESULTS

We identified 202 vegans, 664 vegetarians, 409 pesco-vegetarians, 227 semi-vegetarians, and 1973 nonvegetarians. Compared to the nonvegetarian referent (BMI = 27.50), estimated BMI were lower among vegans (23.58, P < .0001), vegetarians (25.24, P < .0001), pesco-vegetarians (26.36, P = .0002), and semi-vegetarians (26.69, P = .130). Other factors associated with lower BMI were being female (P = .001), nativity (Mexico, P = .002; South America, P < .0001; Caribbean, P = .004), having a college degree or higher (P = .01), exercise (P < .0001), and never smoked (P = .0006).

CONCLUSION

Hispanic/Latino SDAs who consumed plant-based diets had lower BMI than nonvegetarians. The application of a plant-based diet as practiced by the Hispanic/Latino Adventists in this population may have public health impact on US Hispanic/Latinos.

Associations of food insecurity and psychosocial measures with diet quality in adults aging with HIV

People aging with HIV face social stressors which may negatively affect their overall nutrition. Here, we assess relationships between self-reported measures of depression, perceived stress, social support, and food insecurity with diet quality in older adults with HIV. A retrospective analysis of self-reported data from parent study at The University of Alabama at Birmingham 1917 HIV Clinic was performed. The study sample consisted of sixty people living with HIV (PLWH) with controlled HIV infection (<50 copies/mL), aged 50 years or older who participated in a cross-sectional microbiome study. Dietary intake was measured using the NHANES 12-month Food Frequency Questionnaire (FFQ) and three Automated Self-Administered (ASA) 24-hr diet recalls to calculate diet quality scores using the Mediterranean Diet Score (MDS); alternative Healthy Eating Index (aHEI); and the Recommended Food Score (RFS) indices. Food insecurity was measured with the Food Security Questionnaire (FSQ). Participants completed the following psychosocial scales: (1) depression - Patient Health Questionnaire-8 (PHQ8); (2) perceived stress - Perceived Stress Scale (PSS-10); (3) social support - Multidimensional Scale of Perceived Social Support (MSPSS). Linear regression models were used to investigate relationships among variables controlling for gender and income. The cohort was characterized as follows: Mean age 56 ± 4.6 years, 80% African-American, and 32% women. Mean body mass index (BMI) was 28.4 ± 7.2 with 55% reporting food insecurity. Most participants reported having post-secondary education (53%), although 77% reported annual incomes <$20,000. Food insecurity was independently associated with measures of poor dietary intake: aHEI (β = -0.08, p = .02) and MDS (β = -0.23, p < 0.01) and with low dietary intake of fibre (β = -0.27, p = .04), vitamin E (β = -0.35, p = .01), folate (β = -0.31, p = .02), magnesium (β = -0.34, p = .01) and copper (β = -0.36, p = .01). These data indicate food insecurity is associated with poor diet quality among PLWH. Clinical interventions are needed to improve food access for PLWH of low SES.

Comparison of the NHANES dietary screener questionnaire to the Automated Self-Administered 24-Hour Recall for Children in the Healthy Communities Study

Background

A dietary screener questionnaire (DSQ) was used to assess dietary outcomes among children in the Healthy Communities Study (HCS), a study of the relationships between programs and policies to prevent child obesity and child diet, physical activity and weight outcomes.

Methods

To compare dietary intake estimates derived from the DSQ against those from the Automated Self-Administered 24-Hour Recalls for Children (ASA24-Kids) among children, a measurement error model, using structural equation modelling, was utilized to estimate slopes, deattenuated correlation coefficients, and attenuation factors by age and sex, ethnicity, and BMI status.

Participants/setting

A randomly selected sub-sample of HCS participants aged 4–15 years in 130 communities throughout the U.S. who completed the DSQ and up to two ASA24-Kids recalls (n = 656;13% of HCS participants).

Results

For most nutrient/foods examined, the DSQ yielded larger mean intake estimates than the ASA24-Kids, and agreement between the two measures varied by food/nutrient, age and sex, ethnicity, and BMI category. Deattenuated correlation coefficients of 0.4 or greater were observed for added sugars from SSBs (0.54), fruits and vegetables (0.40), and dairy foods (0.50). Lower deattenuated correlation coefficients were seen for total added sugars (0.37), whole grains (0.34), and fiber (0.34). Attenuation factors were most severe for total added sugars intake among overweight children, and for several other dietary outcomes among children aged 9–11 years.

Conclusions

The DSQ was found to be a tool with acceptable agreement with the ASA24-Kids for measuring multiple dietary outcomes of interest in the HCS, although there may be potential due to measurement error to underestimate results (bias towards the null). In future studies, measurement error modelling and regression calibration may be possible solutions to correct for bias due to measurement error in most food/nutrient intake estimates from the DSQ when used among children.

Electronic supplementary material

The online version of this article (10.1186/s12937-018-0415-1) contains supplementary material, which is available to authorized users.

Unscrambling the relations of egg and meat consumption with type 2 diabetes risk

Background

Meat intake is associated with increased risk of type 2 diabetes (T2D). It is not clear if egg intake is associated with T2D risk because purported associations may be due to concurrent consumption of eggs with meat.

Objective

Our aim was to differentiate any associations between meat and egg consumption and the risk of T2D.

Design

In this longitudinal study, 55,851 participants of the Adventist Health Study 2 who were free of diabetes provided demographic, anthropometric, and dietary data at baseline. Meat and egg intakes were assessed with a validated quantitative food-frequency questionnaire. Responses to 2 follow-up questionnaires determined incident T2D cases. Multivariate-adjusted logistic regression was used to determine relations between meat and egg intake and incident T2D.

Results

T2D cases identified during a mean 5.3 y of follow-up totaled 2772. Meat intake of >0 to <25 g/d, ≥25 to <70 g/d, and ≥70 g/d significantly increased the risk of T2D compared with no meat intake (OR: 1.29; 95% CI: 1.16, 1.44; OR: 1.42; 95% CI: 1.25, 1.61; and OR: 1.65; 95% CI: 1.39, 1.96, respectively; P-trend < 0.0001). Egg intake compared with no egg intake was not associated with T2D risk. A significant meat-egg interaction (P = 0.019) showed that within every category of egg intake, there was an incremental rise in T2D risk as meat intake increased. However, within categories of meat intake, increasing egg intake did not increase the risk of T2D except among nonmeat-eaters consuming ≥5 eggs/wk (OR: 1.52; 95% CI: 1.09, 2.12).

Conclusions

Meat consumption, but not egg consumption, is independently associated with T2D risk. Egg intake seems not to increase T2D risk further with meat intake. Our findings suggest that the purported egg-T2D risk relation in US populations may be biased due to failure to investigate egg-meat interactions. Further investigations are needed to ascertain T2D risk among nonmeat-eaters with high egg intakes.

Lower C-reactive protein and IL-6 associated with vegetarian diets are mediated by BMI

BACKGROUND AND AIMS

The mechanism by which vegetarian diets are associated with less inflammation is not clear. We investigated the role of BMI as a mediator in the relationship between vegetarian diet and concentrations of C-reactive protein (CRP), and the cytokines IL-6, IL-10 and TNF-α.

METHODS AND RESULTS

We used data from participants of the Adventist Health Study 2 (AHS-2) Calibration (n = 893) and Biological Manifestations of Religion (n = 478) sub-studies. Vegetarian diet variations were determined based on reported intake of animal products assessed by FFQ. Combining all participants, the proportion of non-vegetarians (NVs), partial vegetarians (PVs), lacto-ovo vegetarians (LOVs), and strict vegetarians (SVs) was 44%, 16%, 31%, and 9%, respectively. NV and PV participants were older than other dietary groups, and non-vegetarians had the highest BMI. Mediation analyses supported the mediating effect of BMI in associations of vegetarian diet with CRP (p < 0.001 each for PV, LOV and SV), and with IL-6 (p < 0.05 each for PV, LOV and SV). Mediation by BMI was not evident between vegetarian diet and the biomarkers IL-10 and TNF-α. A direct pathway was significant only in the association between strict vegetarians and CRP (p = 0.017).

CONCLUSION

The lower CRP and IL-6 concentrations among vegetarians may be mediated by BMI.

A New Approach to Assess Lifetime Dietary Patterns Finds Lower Consumption of Animal Foods with Aging in a Longitudinal Analysis of a Health-Oriented Adventist Population

Life-course diet patterns may impact risk of disease, but little is known about dietary trends with aging. In a retrospective longitudinal analysis we estimated lifetime intake of animal products and adherence to vegetarian dietary patterns among 51,082 Adventist Health Study-2 (AHS-2) subjects using data from a reliable life-course dietary (meats, dairy, eggs) questionnaire. Results showed a marked tendency to consume fewer animal products (in total) in older years and to reduce consumption of meat, poultry and fish, but not eggs or dairy. Among the 29% of elderly subjects who during their lifetime kept the same dietary pattern (LTS) were: LTS-vegans (1.1%), LTS-lacto-ovo vegetarians (31.2%), LTS-pesco vegetarians (0.49%), LTS-semi vegetarians (3.7%), and LTS-non-vegetarians (63.5%). Among the 71% of switchers were “Converters” (59.7%) who moved towards and “Reverters” (9.1%) who moved away from vegetarian diets, and Multiverters (31.2%), who had moved in both directions. LTS-non-vegetarians, and also reverters, were more overweight and showed a less healthy lifestyle than others. We conclude that the dietary patterns are dynamic with strong trends to reduce animal foods and to adopt more vegetarian patterns with aging. The disease experience of subjects with different lifetime dietary patterns can be compared.

Independent associations of dairy and calcium intakes with colorectal cancers in the Adventist Health Study-2 cohort

OBJECTIVE

Results associating dairy and Ca intakes with colorectal cancer (CRC) risk have been mixed. Most previous analyses have suffered from confounding between dairy and Ca intakes. We examined independent associations between these variables, also dairy foods, and CRC incidence in a population with a large range of dairy intakes.

DESIGN

Adventist Health Study-2 is a cohort study where subjects were enrolled 2002-2007. Proportional hazard regression analyses were performed to estimate hazard ratios (HR). Regression calibration was used to correct for dietary measurement error.

SETTING

The population lived in all states of the USA.

SUBJECTS

There were 77712 analytic subjects, all of whom were Seventh-day Adventists. Much of their dietary Ca came from non-dairy sources.

SUBJECTS

During a mean follow-up of 7·8 years, 380 incident colon cancer and 111 incident rectal cancer cases were observed.

RESULTS

Comparing extreme quintiles of intake in measurement error-corrected analyses, dairy intake (HR=0·31; 95 % CI 0·09, 0·88), independent of total Ca, was inversely related with risk of rectal cancer but gave little indication of association with colon cancer. However, total Ca intake (independent of dairy) was associated with risk of colon cancer (HR=0·55; 95 % CI 0·28, 0·98) and there was little indication of association with rectal cancer. Traditional regression analyses and associations with macronutrients from dairy generally supported these results. Milk intake was also negatively associated with CRC (HR=0·63; 95 % CI 0·43, 0·89).

CONCLUSIONS

Dairy intake may decrease the risk of rectal cancer, and Ca may reduce risk of colon cancer and CRC.

Variations in dietary intake and plasma concentrations of plant sterols across plant-based diets among North American adults

SCOPE

Phytosterols are bioactive compounds in plants with similar cholesterol-lowering properties as vegetarian diets. However, information on phytosterol intake and plasma plant sterols among vegetarians is sparse.

METHODS AND RESULTS

We examined dietary intake and plasma concentration of plant sterols and cholesterol across five dietary patterns in the Adventist Health Study-2 Calibration Sub-study (n = 861, 66% females, average age 61 years). To measure intake and plasma concentrations of these compounds, we used 24-h dietary recalls and gas-liquid chromatography-flame ionization detection, respectively. Mean (SD) total phytosterol and cholesterol intake were 363 (176) mg/day and 131 (111) mg/day; plasma β-sitosterol, campesterol, and cholesterol were 3.3 (1.7) μg/mL, 4.2 (2.3) μg/mL, and 1.9 (0.4) mg/mL, respectively. Total phytosterol intake was lowest among non-vegetarians (263 mg/day) and highest among vegans (428 mg/day) (p < 0.0001). Cholesterol intake was lowest among vegans (15.2 mg/day) and highest among non-vegetarians (124.6 mg/day) (p < 0.0001). Plasma plant sterols and cholesterol did not differ by diet. Cholesterol-adjusted plasma β-sitosterol and campesterol were significantly higher in Blacks than Whites, though no ethnic differences were observed in dietary intake of these plant sterols.

CONCLUSION

Dietary intake but not plasma concentration of plant sterols and cholesterol varies across distinct plant-based diets.

Self-Report Dietary Assessment Tools Used in Canadian Research: A Scoping Review

Choosing the most appropriate dietary assessment tool for a study can be a challenge. Through a scoping review, we characterized self-report tools used to assess diet in Canada to identify patterns in tool use and to inform strategies to strengthen nutrition research. The research databases Medline, PubMed, PsycINFO, and CINAHL were used to identify Canadian studies published from 2009 to 2014 that included a self-report assessment of dietary intake. The search elicited 2358 records that were screened to identify those that reported on self-report dietary intake among nonclinical, non-Aboriginal adult populations. A pool of 189 articles (reflecting 92 studies) was examined in-depth to assess the dietary assessment tools used. Food-frequency questionnaires (FFQs) and screeners were used in 64% of studies, whereas food records and 24-h recalls were used in 18% and 14% of studies, respectively. Three studies (3%) used a single question to assess diet, and for 3 studies the tool used was not clear. A variety of distinct FFQs and screeners, including those developed and/or adapted for use in Canada and those developed elsewhere, were used. Some tools were reported to have been evaluated previously in terms of validity or reliability, but details of psychometric testing were often lacking. Energy and fat were the most commonly studied, reported by 42% and 39% of studies, respectively. For ∼20% of studies, dietary data were used to assess dietary quality or patterns, whereas close to half assessed ≤5 dietary components. A variety of dietary assessment tools are used in Canadian research. Strategies to improve the application of current evidence on best practices in dietary assessment have the potential to support a stronger and more cohesive literature on diet and health. Such strategies could benefit from national and global collaboration.

Validating polyphenol intake estimates from a food-frequency questionnaire by using repeated 24-h dietary recalls and a unique method-of-triads approach with 2 biomarkers

Background: The assessment of polyphenol intake in free-living subjects is challenging, mostly because of the difficulty in accurately measuring phenolic content and the wide presence of phenolics in foods.Objective: The aims of this study were to evaluate the validity of polyphenol intake estimated from food-frequency questionnaires (FFQs) by using the mean of 6 measurements of a 24-h dietary recall (24-HR) as a reference and to apply a unique method-of-triads approach to assess validity coefficients (VCs) between latent "true" dietary estimates, total urinary polyphenol (TUP) excretion, and a surrogate biomarker (plasma carotenoids).Design: Dietary intake data from 899 adults of the Adventist Health Study 2 (AHS-2; 43% blacks and 67% women) were obtained. Pearson correlation coefficients (r), corrected for attenuation from within-person variation in the recalls, were calculated between 24-HRs and FFQs and between 24-HRs and TUPs. VCs and 95% CIs between true intake and polyphenol intakes from FFQs, 24-HRs, and the biomarkers TUPs and plasma carotenoids were calculated.Results: Mean ± SD polyphenol intakes were 717 ± 646 mg/d from FFQs and 402 ± 345 mg/d from 24-HRs. The total polyphenol intake from 24-HRs was correlated with FFQs in crude (r = 0.51, P < 0.001) and deattenuated (r = 0.63; 95% CI: 0.61, 0.69) models. In the triad model, the VC between the FFQs and theoretical true intake was 0.46 (95% CI: 0.20, 0.93) and between 24-HRs and true intake was 0.61 (95% CI: 0.38, 1.00).Conclusions: The AHS-2 FFQ is a reasonable indicator of total polyphenol intake in the AHS-2 cohort. Urinary polyphenol excretion is limited by genetic variance, metabolism, and bioavailability and should be used in addition to rather than as a replacement for dietary intake assessment.

The association between soya consumption and serum thyroid-stimulating hormone concentrations in the Adventist Health Study-2

OBJECTIVE

Consumers may choose soya foods as healthful alternatives to animal products, but concern has arisen that eating large amounts of soya may adversely affect thyroid function. The present study aimed to examine the association between soya food consumption and serum thyroid-stimulating hormone (TSH) concentrations in North American churchgoers belonging to the Seventh-day Adventist denomination that encourages vegetarianism.

DESIGN

Participants completed six repeated 24 h dietary recalls within a 6-month period. Soya protein and soya isoflavone intakes were estimated, and their relationships to TSH concentrations measured at the end of 6 months were calculated using logistic regression analyses.

SETTING

Calibration sub-study of the Adventist Health Study-2.

SUBJECTS

Women (n 548) and men (n 295) who were not taking thyroid medications.

RESULTS

In men, age and urinary iodine concentrations were associated with high serum TSH concentrations (>5 mIU/l), while among women White ethnicity was associated with high TSH. In multivariate models adjusted for age, ethnicity and urinary iodine, soya isoflavone and protein intakes were not associated with high TSH in men. In women higher soya isoflavone consumption was associated with higher TSH, with an adjusted odds ratio (highest v. lowest quintile) of 4·17 (95 % CI 1·73, 10·06). Likewise, women with high consumption of soya protein (midpoint of highest quintile, 11 g/d) v. low consumption (midpoint of lowest quintile, 0 g/d) carried increased odds of high TSH (OR=2·69; 95 % CI 1·34, 5·30).

CONCLUSIONS

In women high consumption of soya was associated with elevated TSH concentrations. No associations between soya intake and TSH were found in men.

Trans fatty acid intake is related to emotional affect in the Adventist Health Study-2

Trans fatty acids in Western diets increase health risks, and have been associated with the risk of depression. We hypothesized that intakes of trans fatty acids (primarily from margarines and baked goods) were inversely associated with positive affect and positively associated with negative affect in a longitudinal study. Church attendees residing in North America completed a food frequency questionnaire in 2002-6 as part of the Adventist Health Study-2. A subset in which we excluded participants with established cardiovascular disease (n=8,771) completed the Positive and Negative Affect Schedule (PANAS) in 2006-7. The associations between dietary intakes of fatty acids to positive and negative affect were tested with linear regression analysis controlling for age, gender, ethnicity, education, body mass index, exercise, sleep, sleep squared, Mediterranean diet, total energy intake and alcohol. Intakes of trans fatty acids were inversely associated with positive affect (β=-0.06, B=-0.27 [95% CI -0.37, -0.17], p<.001) and positively associated with negative affect (β=0.05, B=0.21 [95% CI 0.11, 0.31], p<.001). In comparison, we found no association between n-3 polyunsatured fatty acids (PUFA) intakes with affect. The n-6:n-3 PUFA ratio was inversely associated with positive affect (β=-0.03, B=-0.34 [95% CI -0.58, -0.10], p=0.006). The findings suggest that a lower dietary trans fatty acid intake has beneficial effects on emotional affect while the n-6: n-3 ratio is detrimental to positive affect.

Vegetarian dietary patterns and the risk of breast cancer in a low-risk population

Among cancers in American women, breast cancer (BC) has the second highest incidence and mortality. The association of BC with diet has been inconsistent. Studies that evaluate associations with dietary patterns are less common and reflect an individual's whole diet. We associated dietary patterns with the risk of BC in American women of the Adventist Health Study-2 (AHS-2), a prospective cohort of 96 001 subjects recruited between 2002 and 2007. Answers to a previously validated FFQ were used to classify subjects to vegan, lacto-ovo-vegetarian, pesco-vegetarian, semi-vegetarian and non-vegetarian dietary patterns. Incident BC were identified by matching AHS-2 subjects to data from forty-eight state cancer registries. Statistical analyses used proportional hazard regression analyses with covariates that were chosen a priori. From 50 404 female participants (26 193 vegetarians), we identified 892 incident BC cases, with 478 cases among vegetarians. As compared with non-vegetarians, all vegetarians combined did not have a significantly lower risk (hazard ratio (HR) 0·97; CI 0·84, 1·11; P=0·64). However, vegans showed consistently lower (but non-significant) point estimates when compared with non-vegetarians (all cases: HR 0·78; CI 0·58, 1·05; P=0·09). In summary, participants in this cohort who follow a vegetarian dietary pattern did not experience a lower risk of BC as compared with non-vegetarians, although lower risk in vegans is possible. These findings add to the very limited literature associating vegetarian diets with BC risk and can assist nutritionists when evaluating the impact of these diets. The findings will also motivate further evaluation of vegan diets and their special characteristics.

Biomarkers of Dietary Intake Are Correlated with Corresponding Measures from Repeated Dietary Recalls and Food-Frequency Questionnaires in the Adventist Health Study-2

BACKGROUND

Accurate assessment of diet in study populations is still a challenge. Some statistical strategies that use biomarkers of dietary intake attempt to compensate for the biasing effects of reporting errors.

OBJECTIVE

The objective was to correlate biomarkers of dietary intake with 2 direct measures of dietary intake.

METHODS

Subjects provided repeated 24-h dietary recalls and 2 food-frequency questionnaires (FFQs) separated by ∼3 y. Correlations between biomarkers and reported dietary intakes as measured by the recalls and FFQs were de-attenuated for within-person variability. The Adventist Health Study-2 (AHS-2) has a large database of biomarkers of dietary intake (blood, urine, adipose tissue) from a calibration study (909 analytic subjects) representing the cohort. Participants were black and non-black Adventists in the United States and Canada.

RESULTS

Dietary items with higher-valued de-attenuated correlations (≥0.50) between biomarkers and recalls included some fatty acids (FAs), the non-fish meats, fruit (non-black subjects), some carotenoids, vitamin B-12 (non-black subjects), and vitamin E. Moderately valued correlations (0.30-0.49) were found for very long chain ω-3 (n-3) FAs, some carotenoids, folate, isoflavones, cruciferous vegetables, fruit (black subjects), and calcium. The highest correlation values in non-black and black subjects were 0.69 (urinary 1-methyl-histidine and meat consumption) and 0.72 (adipose and dietary 18:2 ω-6), respectively. Correlations comparing biomarkers with recalls were generally similar for black and non-black subjects, but correlations between biomarkers and the FFQ were slightly lower than corresponding recall correlations. Correlations between biomarkers and a single FFQ estimate (the usual cohort situation) were generally much lower.

CONCLUSIONS

Many biomarkers that have relatively high-valued correlations with dietary intake were identified and were usually of similar value in black and non-black subjects. These may be used to correct effects of dietary measurement errors in the AHS-2 cohort, and in some cases they also provide evidence supporting the validity of the dietary data.

Diet-related greenhouse gas emissions assessed by a food frequency questionnaire and validated using 7-day weighed food records

BACKGROUND

The current food system generates about 25 % of total greenhouse gas emissions (GHGE), including deforestation, and thereby substantially contributes to the warming of the earth's surface. To understand the association between food and nutrient intake and GHGE, we therefore need valid methods to assess diet-related GHGE in observational studies.

METHODS

Life cycle assessment (LCA) studies assess the environmental impact of different food items. We linked LCA data expressed as kg carbon dioxide equivalents (CO2e) per kg food product to data on food intake assessed by the food frequency questionnaire (FFQ) Meal-Q and validated it against a 7-day weighed food record (WFR). 166 male and female volunteers aged 20-63 years completed Meal-Q and the WFR, and their food intake was linked to LCA data.

RESULTS

The mean GHGE assessed with Meal-Q was 3.76 kg CO2e per day and person, whereas it was 5.04 kg CO2e using the WFR. The energy-adjusted and deattenuated Pearson and Spearman correlation coefficients were 0.68 and 0.70, respectively. Moreover, compared to the WFR, Meal-Q provided a good ranking ability, with 90 % of the participants classified into the same or adjacent quartile according to their daily average CO2e. The Bland-Altman plot showed an acceptable level of agreement between the two methods and the reproducibility of Meal-Q was high.

CONCLUSIONS

This is the first study validating the assessment of diet-related GHGE by a questionnaire. The results suggest that Meal-Q is a useful tool for studying the link between food habits and CO2e in future epidemiological studies.

Are strict vegetarians protected against prostate cancer?

BACKGROUND

According to the American Cancer Society, prostate cancer accounts for ∼27% of all incident cancer cases among men and is the second most common (noncutaneous) cancer among men. The relation between diet and prostate cancer is still unclear. Because people do not consume individual foods but rather foods in combination, the assessment of dietary patterns may offer valuable information when determining associations between diet and prostate cancer risk.

OBJECTIVE

This study aimed to examine the association between dietary patterns (nonvegetarian, lacto-ovo-vegetarian, pesco-vegetarian, vegan, and semi-vegetarian) and prostate cancer incidence among 26,346 male participants of the Adventist Health Study-2.

DESIGN

In this prospective cohort study, cancer cases were identified by matching to cancer registries. Cox proportional hazards regression analysis was performed to estimate HRs by using age as the time variable.

RESULTS

In total, 1079 incident prostate cancer cases were identified. Around 8% of the study population reported adherence to the vegan diet. Vegan diets showed a statistically significant protective association with prostate cancer risk (HR: 0.65; 95% CI: 0.49, 0.85). After stratifying by race, the statistically significant association with a vegan diet remained only for the whites (HR: 0.63; 95% CI: 0.46, 0.86), but the multivariate HR for black vegans showed a similar but nonsignificant point estimate (HR: 0.69; 95% CI: 0.41, 1.18).

CONCLUSION

Vegan diets may confer a lower risk of prostate cancer. This lower estimated risk is seen in both white and black vegan subjects, although in the latter, the CI is wider and includes the null.

The reliability and validity of a short food frequency questionnaire among 9-11-year olds: a multinational study on three middle-income and high-income countries

OBJECTIVE

The main aim of this study was to assess the reliability and validity of a food frequency questionnaire with 23 food groups (I-FFQ) among a sample of 9-11-year-old children from three different countries that differ on economical development and income distribution, and to assess differences between country sites. Furthermore, we assessed factors associated with I-FFQ's performance.

METHODS

This was an ancillary study of the International Study of Childhood Obesity, Lifestyle and the Environment. Reliability (n=321) and validity (n=282) components of this study had the same participants. Participation rates were 95% and 70%, respectively. Participants completed two I-FFQs with a mean interval of 4.9 weeks to assess reliability. A 3-day pre-coded food diary (PFD) was used as the reference method in the validity analyses. Wilcoxon signed-rank tests, intraclass correlation coefficients and cross-classifications were used to assess the reliability of I-FFQ. Spearman correlation coefficients, percentage difference and cross-classifications were used to assess the validity of I-FFQ. A logistic regression model was used to assess the relation of selected variables with the estimate of validity. Analyses based on information in the PFDs were performed to assess how participants interpreted food groups.

RESULTS

Reliability correlation coefficients ranged from 0.37 to 0.78 and gross misclassification for all food groups was <5%. Validity correlation coefficients were below 0.5 for 22/23 food groups, and they differed among country sites. For validity, gross misclassification was <5% for 22/23 food groups. Over- or underestimation did not appear for 19/23 food groups. Logistic regression showed that country of participation and parental education were associated (P⩽0.05) with the validity of I-FFQ. Analyses of children's interpretation of food groups suggested that the meaning of most food groups was understood by the children.

CONCLUSION

I-FFQ is a moderately reliable method and its validity ranged from low to moderate, depending on food group and country site.

Vegetarian dietary patterns and the risk of colorectal cancers

IMPORTANCE

Colorectal cancers are a leading cause of cancer mortality, and their primary prevention by diet is highly desirable. The relationship of vegetarian dietary patterns to colorectal cancer risk is not well established.

OBJECTIVE

To evaluate the association between vegetarian dietary patterns and incident colorectal cancers.

DESIGN, SETTING, AND PARTICIPANTS

The Adventist Health Study 2 (AHS-2) is a large, prospective, North American cohort trial including 96,354 Seventh-Day Adventist men and women recruited between January 1, 2002, and December 31, 2007. Follow-up varied by state and was indicated by the cancer registry linkage dates. Of these participants, an analytic sample of 77,659 remained after exclusions. Analysis was conducted using Cox proportional hazards regression, controlling for important demographic and lifestyle confounders. The analysis was conducted between June 1, 2014, and October 20, 2014.

EXPOSURES

Diet was assessed at baseline by a validated quantitative food frequency questionnaire and categorized into 4 vegetarian dietary patterns (vegan, lacto-ovo vegetarian, pescovegetarian, and semivegetarian) and a nonvegetarian dietary pattern.

MAIN OUTCOMES AND MEASURES

The relationship between dietary patterns and incident cancers of the colon and rectum; colorectal cancer cases were identified primarily by state cancer registry linkages.

RESULTS

During a mean follow-up of 7.3 years, 380 cases of colon cancer and 110 cases of rectal cancer were documented. The adjusted hazard ratios (HRs) in all vegetarians combined vs nonvegetarians were 0.78 (95% CI, 0.64-0.95) for all colorectal cancers, 0.81 (95% CI, 0.65-1.00) for colon cancer, and 0.71 (95% CI, 0.47-1.06) for rectal cancer. The adjusted HR for colorectal cancer in vegans was 0.84 (95% CI, 0.59-1.19); in lacto-ovo vegetarians, 0.82 (95% CI, 0.65-1.02); in pescovegetarians, 0.57 (95% CI, 0.40-0.82); and in semivegetarians, 0.92 (95% CI, 0.62-1.37) compared with nonvegetarians. Effect estimates were similar for men and women and for black and nonblack individuals.

CONCLUSIONS AND RELEVANCE

Vegetarian diets are associated with an overall lower incidence of colorectal cancers. Pescovegetarians in particular have a much lower risk compared with nonvegetarians. If such associations are causal, they may be important for primary prevention of colorectal cancers.

Short- and long-term reliability of adult recall of vegetarian dietary patterns in the Adventist Health Study-2 (AHS-2)

Past dietary patterns may be more important than recent dietary patterns in the aetiology of chronic diseases because of the long latency in their development. We developed an instrument to recall vegetarian dietary patterns during the lifetime and examined its reliability of recall over 5·3 and 32·6 years on average. The short-term/5-year recall ability study (5-RAS) was done using 24 690 participants from the cohort of the Adventist Health Study-2 (mean age 62·2 years). The long-term/33-year recall ability study (33-RAS) included an overlap population of 1721 individuals who joined the Adventist Health Study-1 and Adventist Health Study-2 (mean age 72·5 years). Spearman correlation coefficients for recall of vegetarian status were 0·78 and 0·72 for the 5-RAS and 33-RAS, respectively, when compared with 'reference' data. For both time periods sensitivity and positive predictive values were highest for the lacto-ovo-vegetarian and non-vegetarian patterns (vegans, lacto-ovo-vegetarians, pesco-vegetarians, semi-vegetarians and non-vegetarians). In the 5-RAS analyses, male, non-black, younger, and more educated participants, lifetime Adventists, and those with more stability of consumption of animal products generally showed higher recall ability. Somewhat similar tendencies were shown for the 33-RAS analyses. Our findings show that the instrument has higher reliability for recalled lacto-ovo-vegetarian and non-vegetarian than for vegan, semi- and pesco-vegetarian dietary patterns in both short- and long-term recalls. This is in part because these last dietary patterns were greatly contaminated by recalls that correctly would have belonged in the adjoining category that consumed more animal products.

Impact of Walking and Running on the Heel bone: the Adventist Health Study-2

Aims

Physical activity is well recognized for its bone health benefit. We examined the benefit of walk/run/jog on bone health using broadband ultrasound attenuation (BUA) of the calcaneus.

Methodology

Caucasian and African American males (n=593) and females (n=1,106) had their calcaneal BUA measured two years later after enrollment into the AHS-2. The association between calcaneal BUA (dB/Mhz) and the distance of walk/run/ jog level per week (miles) was assessed using multiple linear regression.

Results

In a multivariable model adjusted for important covariates, BUA was positively associated with BMI (P < .001), total calcium intake (P =0.31), total protein intake (P =0.38) and inversely associated with age (P < .001) and smoking (P < .05). Compared to women who did not walk/ run/ jog, women walking 10 or more miles per week had an increase in BUA by 4.08 (dB/Mhz) (P _trend=0.03). Similarly, compared to men who did not walk/ run/ jog, men walking 10 or more miles per week had an increase in BUA by 5.97 (dB/Mhz) (P _trend=0.01).

Conclusions

We concluded that BUA is positively associated with walk/ run/jog after accounting for age, BMI, smoking status, calcium intake, protein intake and estrogen usage.

Patterns of food consumption among vegetarians and non-vegetarians

Vegetarian dietary patterns have been reported to be associated with a number of favourable health outcomes in epidemiological studies, including the Adventist Health Study 2 (AHS-2). Such dietary patterns may vary and need further characterisation regarding foods consumed. The aims of the present study were to characterise and compare the food consumption patterns of several vegetarian and non-vegetarian diets. Dietary intake was measured using an FFQ among more than 89 000 members of the AHS-2 cohort. Vegetarian dietary patterns were defined a priori, based on the absence of certain animal foods in the diet. Foods were categorised into fifty-eight minor food groups comprising seventeen major food groups. The adjusted mean consumption of each food group for the vegetarian dietary patterns was compared with that for the non-vegetarian dietary pattern. Mean consumption was found to differ significantly across the dietary patterns for all food groups. Increased consumption of many plant foods including fruits, vegetables, avocados, non-fried potatoes, whole grains, legumes, soya foods, nuts and seeds was observed among vegetarians. Conversely, reduced consumption of meats, dairy products, eggs, refined grains, added fats, sweets, snack foods and non-water beverages was observed among vegetarians. Thus, although vegetarian dietary patterns in the AHS-2 have been defined based on the absence of animal foods in the diet, they differ greatly with respect to the consumption of many other food groups. These differences in food consumption patterns may be important in helping to explain the association of vegetarian diets with several important health outcomes.

Relationship of 6-n-propylthiouracil taste intensity and chili pepper use with body mass index, energy intake, and fat intake within an ethnically diverse population

BACKGROUND

One of the weight-loss strategies that has attracted attention is the use of spicy foods. It has been suggested that spicy food preference is related to a genetically predetermined sensitivity to the bitter compound 6-n-propylthiouracil (PROP).

OBJECTIVE

Our aim was to examine the relationship of PROP taste intensity and hot chili pepper use with body mass index (BMI), energy intake, and fat intake.

DESIGN

This study utilized a cross-sectional design.

PARTICIPANTS/SETTING

The sample included 350 subjects (154 male, 196 female) ages 18 to 55 years living in the New York City area.

MAIN OUTCOME MEASURES

BMI was calculated by measuring weight and height, and the sensitivity to PROP was evaluated using the PROP filter paper method. Subjects also rated the frequency of usage and preference for hot chili pepper using a chili pepper questionnaire. Their daily energy and fat intake were assessed using a food frequency questionnaire.

STATISTICAL ANALYSES PERFORMED

An independent sample t-test compared subject characteristics between groups based on sex, PROP status, and hot chili pepper user status for the continuous variables, and the χ(2) test was used for categorical variables. One-way analysis variance examined the differences in subject characteristics across four ethnicities. To predict BMI, energy intake, and fat intake, multiple linear regression models were fit with the covariates of age, sex, ethnicity, chili pepper score, and PROP mean.

RESULTS

The values for BMI, energy intake, and fat intake of PROP tasters were significantly lower than those of PROP nontasters (P=0.03, P<0.001, and P<0.001, respectively). The energy intake of chili pepper nonusers was significantly lower than that of chili pepper users (P=0.02), while there was no significant difference in fat intake between chili pepper users and nonusers.

CONCLUSIONS

This study suggests that PROP taste sensitivity contributes more to the prediction of energy and fat intake than chili pepper use.

Mediterranean diet and emotion regulation

BACKGROUND

Mediterranean dietary patterns have been associated with cardiovascular and psychological health, including positive affect. Emotion regulation has not been linked to this pattern.

OBJECTIVE

The present study prospectively examined the relationship between Mediterranean diet and later emotion regulation and whether positive or negative affect mediated any such relationship.

METHODS

Data was derived from the Adventist Health Study-2 (2002-6), and Biopsychosocial Religion and Health Substudy (2006-7; 2010-11). We assessed adherence to Mediterranean diet using the Trichopoulou score at baseline, and responses to Positive and Negative Affect Schedule (2006-7) and Difficulties in Emotion Regulation Scale (2010-11) in 1,699 men and 3,293 women. Statistical analyses were performed using multiple linear regression and Hayes PROCESS SPSS macros.

RESULTS

Mediterranean dietary adherence scores were inversely related to difficulty with clarity of emotional responses (B =-0.013, p = 0.006, 95% CI [-0.23, -0.004]) but unrelated to difficulty with awareness of emotional responses or lack of access to strategies for regulating emotions. Positive and negative affect fully mediated the diet and clarity relationship by respectively decreasing and increasing difficulty with clarity (effect scores -0.007 [95% CI -0.009, -0.005] and -0.005 [95% CI -0.008, -0.003]).

CONCLUSIONS

Mediterranean diet adherence showed association with emotional clarity via increasing positive and decreasing negative affect.