Rice intake is associated with reduced risk of mortality from cardiovascular disease in Japanese men but not women.

Rice is a staple food in Japan and provides 43% of carbohydrate and 29% of energy intake in the Japanese population. In a prospective study encompassing 83,752 Japanese men and women aged 40-79 y, rice intake was determined by self-administered FFQ. Median follow-up time was 14.1 y from 1988-1990 to the end of 2003, and HR and 95% CI of mortality were calculated according to quintiles of energy-adjusted rice intake. A total of 3514 cardiovascular deaths [1640 strokes, 707 coronary heart disease (CHD), and 560 heart failure] were documented. There was a gender difference on the effect of rice intake on the risk of cardiovascular disease (CVD). Overall, rice intake was inversely associated with CHD, heart failure, and total CVD in men but not in women. Rice intake was not associated with risk of stroke in either gender. The multivariable HR (95% CI) for the extreme quintiles of rice intake in men were 0.70 [(0.49-0.99); P-trend = 0.02] for CHD, 0.70 [(0.46-1.05); P-trend = 0.05] for heart failure, and 0.82 [(0.70-0.97); P-trend = 0.006] for total CVD. For women, rice was not associated with reduced risk of mortality from CVD after adjusting for lifestyle and dietary variables. In conclusion, the consumption of steamed rice was associated with reduced risk of mortality from CVD in Japanese men but not women. This finding necessitates further investigations on the mechanisms leading to this gender difference.