Relationship between vegetable and carotene intake and risk of prostate cancer: the JACC study.

BACKGROUND: We examined the associations of intakes of vegetables and carotenes with risk of prostate cancer in Japanese. METHODS: A total of 15,471 Japanese men participating in the Japan Collaborative Cohort study completed a questionnaire including food intake. Of them, 143 incident prostate cancers were documented. We examined the associations stated above by using Cox proportional hazard model. RESULTS: Vegetable intake was not associated with the risk of prostate cancer, but so was dietary alpha-carotene intake. The multivariable hazard ratio (95%CI) in the secondary highest and highest quintiles of alpha-carotene intake was 0.50 (0.26-0.98) (P=0.043) and 0.46 (0.22-0.97) (P=0.041) (P for trend=0.224), respectively. Beta-carotene intake was not associated with the risk of prostate cancer. CONCLUSION: Alpha-carotene intake was associated with lower risk of prostate cancer among Japanese.