OBJECTIVETo assess intake of folate/folic acid and food sources in Japanese female dietitians.

SUBJECTS AND METHODSWe evaluated folate consumption based on four season 7 consecutive day weighed diet records (WDRs) provided by 80 Japanese female dietitians and compared the results with data from a national survey. We then selected informative foods for folate intake on the basis of 2,240 WDRs according to contribution and multiple regression analyses.

RESULTSDaily folate consumption (mean±SD) among Japanese dietitians was 413±158 μg from raw foods and 343±128 μg from cooked foods. Average residual rate after cooking was 84±8%. Folate intake in summer was lower than that in other seasons by analysis of variance. According to contribution and multiple regression analyses, the major contributors were vegetables, fruit and green tea.

CONCLUSIONSDaily folate intake among Japanese female dietitians was far greater than the 200 μg recommended daily allowance for the Japanese. Irrespective of selection methods and raw/cooked foods, major folate sources were found to be green tea along with vegetables and fruit.

Background/Aims: Nutritional factors associated with gastric cancer (GC) are not completely understood. We aimed to determine the effect of nutrient intake on the incidence of GC. Methods: This was a post hoc analysis of a prospective trial that evaluated modalities for GC screening in participants aged 30 to 74 years living in high-risk areas for GC in Japan between June 2011 and March 2013. The patients were followed up for GC incidence for 6 years. All participants completed a self-administered food frequency questionnaire (FFQ) upon enrollment before GC screening. Daily nutrient intake was calculated from the FFQ and dichotomized at each cutoff value using receiver operating characteristic analysis. Risk factors associated with GC incidence were investigated in terms of nutrient intake and participant characteristics using Cox proportional hazards regression analysis. Results: Overall, 1,147 participants were included in this analysis. The median age was 62 years, and 50.7% of the participants were men. The median follow-up period was 2,184 days.GC was detected in 25 participants during the follow-up. Multivariate Cox proportional hazards regression analysis revealed that the intake of sodium (adjusted hazards ratio [aHR], 3.905; 95% confidence interval [CI], 1.520 to 10.035; p=0.005) and vitamin D (aHR, 2.747; 95% CI, 1.111 to 6.788, p=0.029) were positively associated with GC incidence, whereas the intake of soluble dietary fiber (aHR, 0.104; 95% CI, 0.012 to 0.905; p=0.040) was inversely associated with GC incidence. Conclusions Daily high intake of sodium and vitamin D and low soluble dietary fiber intake are associated with GC incidence.

PURPOSE: The purpose of this study was to evaluate the reproducibility and validity of a short food frequency questionnaire (FFQ) for food group intake in Japan, the reproducibility and partial validity of which were previously confirmed for nutrients. METHODS: A total of 288 middle-aged healthy volunteers from 11 different areas of Japan provided nonconsecutive 3-day weighed dietary records (DRs) at 3-month intervals over four seasons. We evaluated reproducibility based on the first (FFQ1) and second (FFQ2) questionnaires and their validity against the DRs by comparing the intake of 20 food groups. Spearman's rank correlation coefficients (SRs) were calculated between energy-adjusted intake from the FFQs and that from the DRs. RESULTS: The intake of 20 food groups estimated from the two FFQs was mostly equivalent. The median energy-adjusted SRs between the FFQ1 and FFQ2 were 0.61 (range 0.38-0.86) for men and 0.66 (0.45-0.84) for women. For validity, the median de-attenuated SRs between DRs and the FFQ1 were 0.51 (0.17-0.76) for men and 0.47 (0.23-0.77) for women. Compared with the DRs, the proportion of cross-classification into exact plus adjacent quintiles with the FFQ1 ranged from 58 to 86% in men and from 57 to 86% in women. According to the robust Z scores and the Bland-Altman plot graphs, the underestimation errors in the FFQ1 tended to be greater in individuals with high mean levels of consumption for meat for men and for other vegetables for both men and women. CONCLUSION The FFQ demonstrated high reproducibility and reasonable validity for food group intake. This questionnaire is short and remains appropriate for identifying associations between diet and health/disease among adults in Japan.
Adult ; Aged ; Diet/statistics & numerical data* ; Diet Surveys ; Energy Intake ; Female ; Food/statistics & numerical data* ; Healthy Volunteers ; Humans ; Japan ; Male ; Middle Aged ; Reproducibility of Results