Objective

To assess race-specific validity of food and food group intakes measured using an FFQ.

Design

Calibration study participants were randomly selected from the Adventist Health Study-2 (AHS-2) cohort by church, and then by subject-within-church. Intakes of forty-seven foods and food groups were assessed using an FFQ and then compared with intake estimates measured using six 24 h dietary recalls (24HDR). We used two approaches to assess the validity of the questionnaire: (i) cross-classification by quartile and (ii) de-attenuated correlation coefficients.

Setting

Seventh-day Adventist church members geographically spread throughout the USA and Canada.

Subjects

Members of the AHS-2 calibration study (550 whites and 461 blacks).

Results

The proportion of participants with exact quartile agreement in the FFQ and 24HDR averaged 46% (range: 29–87%) in whites and 44% (range: 25–88%) in blacks. The proportion of quartile gross misclassification ranged from 1 % to 11 % in whites and from 1 % to 15% in blacks. De-attenuated validity correlations averaged 0·59 in whites and 0·48 in blacks. Of the forty-seven foods and food groups, forty-three in whites and thirty-three in blacks had validity correlations >0·4.

Conclusions

The AHS-2 questionnaire has good validity for most foods in both races; however, validity correlations tend to be higher in whites than in blacks.

Background

Inflammation is a common pathophysiological pathway for a number of chronic diseases, and is strongly influenced by sociodemographic factors and lifestyle. Less is known about factors that may influence the inflammatory response in individuals of distinct ethnic backgrounds. Therefore, this study examined the relationship between ethnicity and blood levels of inflammatory markers in a sample of non-smoking church-goers.

Methods

In a cross-sectional investigation, 508 men and women (>35 years old, 62% White, 38% Black) participated in the Biopsy-chosocial Religion and Health substudy of the Adventist Health Study 2. The contribution of socioeconomic status (education level and difficulty meeting expenses for basic needs) and health covariates (exercise, vegetarian or other type of diet, body mass index, and presence of inflammatory conditions) toward serum levels of C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) was assessed with linear regression models. Levels of interleukin-10 (IL-10), an anti-inflammatory marker, were also assessed.

Results

Blacks showed higher levels of CRP and IL-6 than Whites. Controlling for socio-demographic and health variables attenuated the ethnic difference in CRP while IL-6 levels remained higher in Blacks than in Whites (β=.118; 95% confidence interval=.014–.206; P=.025). Ethnic differences in IL-10 and TNF-α were not found. Vegetarian diet was associated with lower CRP levels while exercise frequency was associated with higher IL-10 levels.

Conclusion

Higher susceptibility of Blacks to inflammatory diseases may reflect higher IL-6, which could be important in assessing health disparities among Blacks and Whites. Vegetarian diet and exercise may counteract effects of disparities.

Objective

To validate a 204-item quantitative FFQ for measurement of nutrient intake in the Adventist Health Study-2 (AHS-2).

Design

Calibration study participants were randomly selected from the AHS-2 cohort by church, and then subject-within-church. Each participant provided two sets of three weighted 24 h dietary recalls and a 204-item FFQ. Race-specific correlation coefficients (r), corrected for attenuation from within-person variation in the recalls, were calculated for selected energy-adjusted macro- and micronutrients.

Setting

Adult members of the AHS-2 cohort geographically spread throughout the USA and Canada.

Subjects

Calibration study participants included 461 blacks of American and Caribbean origin and 550 whites.

Results

Calibration study subjects represented the total cohort very well with respect to demographic variables. Approximately 33 % were males. Whites were older, had higher education and lower BMI compared with blacks. Across fifty-one variables, average deattenuated energy-adjusted validity correlations were 0·60 in whites and 0·52 in blacks. Individual components of protein had validity ranging from 0·40 to 0·68 in blacks and from 0·63 to 0·85 in whites; for total fat and fatty acids, validity ranged from 0·43 to 0·75 in blacks and from 0·46 to 0·77 in whites. Of the eighteen micronutrients assessed, sixteen in blacks and sixteen in whites had deattenuated energy-adjusted correlations ≥0·4, averaging 0·60 and 0·53 in whites and blacks, respectively.

Conclusions

With few exceptions validity coefficients were moderate to high for macronutrients, fatty acids, vitamins, minerals and fibre. We expect to successfully use these data for measurement error correction in analyses of diet and disease risk.

Background

Figs are a rich source of soluble fiber. We evaluated the effect of consuming dried California Mission figs on serum lipids in hyperlipidemic adults.

Methods

In a crossover trial men and women aged 30–75 years with elevated low-density lipoprotein cholesterol (100–189 mg/dl) were randomized to add dried California Mission figs (120 g/day) to their usual diet for 5 weeks or eat their usual diet for 5 weeks, then crossed over to the other condition for another 5 weeks. Six 24-hour dietary recalls were obtained.

Results

Low- and high-density lipoprotein cholesterol and triglyceride concentrations did not differ between usual and figs-added diets (Bonferroni-corrected p > 0.017), while total cholesterol tended to increase with fig consumption (p = 0.02). Total cholesterol increased in participants (n = 41) randomized to usual followed by figs-added diet (p = 0.01), but remained unchanged in subjects (n = 42) who started with figs-added followed by usual diet (p = 0.4). During the figs-added diet, soluble fiber intake was 12.6 ± 3.7 versus 8.2 ± 4.1 g/day in the usual diet (p < 0.0001). Sugar intake increased from 23.4 ± 6.5 to 32.2 ± 6.3% of kcal in the figs-added diet (p < 0.0001). Body weight did not change (p = 0.08).

Conclusions

Daily consumption of figs did not reduce low-density lipoprotein cholesterol. Triglyceride concentrations were not significantly changed despite an increase in sugar intake.