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OBJECTIVE -Dietary patterns in Western populations have been linked to type 2 diabetes, but the role of diet in Japanese remains unclear. We investigated the association between major dietary patterns and glucose tolerance status as measured by A1C in Japanese adults.RESEARCH DESIGN AND METHODS -The groups of subjects were comprised of 3,243 men and 4,667 women who participated in the baseline survey of an ongoing cohort study on lifestyle-related diseases in Fukuoka, Japan. Dietary patterns were derived by using principalcomponent analysis of the consumption of 49 food items, ascertained by a food-frequency questionnaire. Logistic regression analysis was used to estimate sex-specific odds ratios (ORs) of elevated A1C (Ն5.5%), with adjustment for potential confounding variables.RESULTS -The Westernized breakfast pattern characterized by frequent intake of bread but infrequent intake of rice was inversely related to A1C concentrations (P trend ϭ 0.02 in both men and women); the multivariate-adjusted ORs for the highest versus lowest quintiles were 0.60 (95% CI 0.43-0.84) and 0.64 (0.46 -0.90) for men and women, respectively. The seafood dietary pattern was positively associated with A1C concentrations in men only (P trend ϭ 0.01). Neither the healthy nor high-fat dietary pattern was related to A1C.CONCLUSIONS -A dietary pattern featuring frequent intake of white rice may deteriorate glucose metabolism in Japanese men and women, and the salty seafood dietary pattern may have a similar effect in men.

Accumulating evidence suggests that vitamin D has anticarcinogenic effects. However, it is unclear whether the nutrient is involved in the early stage of colorectal carcinogenesis. We examined the association between circulating vitamin D concentrations and colorectal adenomas in Japanese men. The study subjects comprised 656 cases of colorectal adenomas and 648 controls with normal colonoscopy among male self defense officials receiving a pre-retirement health examination between 1997 and 2004. Plasma or serum levels of 25-hydroxyvitamin D [25(OH)D] were measured using a radioimmunoassay method. Logistic regression analysis was used to obtain odds ratios (OR) and 95% confidence intervals (CI) with adjustment for potential confounding variables. Overall, there was no measurable association between circulating 25(OH)D concentrations and colorectal adenomas. When the analysis was restricted to subjects whose blood was taken during the winter season (November-April), the prevalence odds of colorectal adenomas for the highest versus lowest quartile of 25(OH)D was statistically significantly decreased (OR = 0.58; 95% CI = 0.34-0.99). The reduction was more pronounced for the rectum (OR = 0.22) and distal colon (OR = 0.47) than for proximal colon (OR = 0.70). During the summer season (May-October), higher levels of 25(OH)D were associated with an increased odds of small, but not large, adenomas. The present study adds to evidence that high levels of circulating vitamin D measured during darker season is associated with decreased prevalence of adenomas in the distal sites of the colorectum. (Cancer Sci 2010; 101: 1695-1700 T he protective role of vitamin D has recently drawn much interest in colorectal carcinogenesis.(1-3) Vitamin D has long been known to enhance intestinal absorption of calcium, (3) which has also been associated with decreased risk of colorectal cancer.(4) Natural sources of vitamin D are production in the skin by solar exposure, fish oil, and shiitake mushroom. The hypothesis that vitamin D is protective against colorectal cancer in humans was proposed on the basis of a geographical correlation between sunlight exposure and colon cancer mortality in the USA.(5) Subsequently, cohort and case-control studies have observed a fairly consistent, protective association between vitamin D intake and colon or colorectal cancer, as reviewed comprehensively elsewhere.(1) Furthermore, decreased risk of colon, rectal, or colorectal cancer has been observed in individuals with higher circulating 25(OH)D levels in several prospective studies (6)(7)(8)(9)(10)(11)(12) although not all studies have found such an association.(13) With regard to colorectal adenomas, a wellestablished precursor lesion of colorectal cancer, (14,15) six casecontrol studies have addressed the association with plasma or serum concentrations of 25(OH)D, reporting a protective association for adenoma prevalence (16)(17)(18) and recurrence (19,20) consistently with one exception. (21) Of particular interest is a recent observation that an inve...