Rice intake and type 2 diabetes in Japanese men and women: the Japan Public Health Center-based Prospective Study.
BACKGROUND
Refined carbohydrates have been suggested to deteriorate glucose metabolism; however, whether persons with elevated intakes of white rice, which is a major staple food for the Japanese, experience increased risk of developing type 2 diabetes remains unclear.


OBJECTIVE
We prospectively investigated the association between white rice intake and risk of type 2 diabetes.


METHODS
Participants were 25,666 men and 33,622 women aged 45-75 y who participated in the second survey of the Japan Public Health Center-based Prospective Study and who had no prior history of diabetes. We ascertained food intake by using a validated 147-item food-frequency questionnaire. Odds ratios of self-reported, physician-diagnosed type 2 diabetes over 5 y were estimated by using logistic regressions.


RESULTS
A total of 1103 new cases of type 2 diabetes were self-reported. There was a significant association between rice intake and an increased risk of type 2 diabetes in women; the multivariate-adjusted odds ratio for the highest compared with lowest quartiles of rice intake was 1.65 (95% CI: 1.06, 2.57; P for trend = 0.005). In men, the association was unclear, although there was a suggestion of a positive association in persons who were not engaged in strenuous physical activity (P for trend = 0.08).


CONCLUSIONS
Elevated intake of white rice is associated with an increased risk of type 2 diabetes in Japanese women. The finding that is suggestive of a positive association of rice intake in physically inactive men deserves further investigation.
Nanri
Akiko
A
Department of Epidemiology and International Health, International Clinical Research Center, National Center for Global Health and Medicine, Tokyo, Japan. nanri@ri.ncgm.go.jp
Mizoue
Tetsuya
T
Noda
Mitsuhiko
M
Takahashi
Yoshihiko
Y
Kato
Masayuki
M
Inoue
Manami
M
Tsugane
Shoichiro
S
D000368:Aged; D002241:Carbohydrates / Q000009:adverse effects*; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000209:etiology*; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D002523:Edible Grain; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012275:Oryza; D005082:Physical Exertion / Q000502:physiology*; D011446:Prospective Studies; D012307:Risk Factors; D057566:Self Report; D012737:Sex Factors; D011795:Surveys and Questionnaires
D002241:Carbohydrates; D004040:Dietary Carbohydrates