Obesity and risk of cancer in Japan
Article first published online: 25 AUG 2004
Copyright © 2004 Wiley-Liss, Inc.
International Journal of Cancer
Volume 113, Issue 1, pages 148–157, 1 January 2005
How to Cite
Kuriyama, S., Tsubono, Y., Hozawa, A., Shimazu, T., Suzuki, Y., Koizumi, Y., Suzuki, Y., Ohmori, K., Nishino, Y. and Tsuji, I. (2005), Obesity and risk of cancer in Japan. Int. J. Cancer, 113: 148–157. doi: 10.1002/ijc.20529
- Issue published online: 25 OCT 2004
- Article first published online: 25 AUG 2004
- Manuscript Accepted: 22 JUN 2004
- Manuscript Received: 16 MAR 2004
- Japanese Ministry of Health and Welfare
- Japanese Ministry of Education, Science, and Culture
- population attributable fraction
We conducted a population-based prospective cohort study in Japan to examine the relationship between body mass index (BMI) and the risk of incidence of any cancer and of cancer at individual sites. Body mass index was calculated from self-administered body weight and height at baseline. Relative risks (RR) and 95% confidence intervals (CI) were calculated in multivariate proportional-hazards models. Among 27,539 persons (15,054 women and 12,485 men) aged 40 years or older who were free of cancer at enrollment in 1984, 1,672 (668 women and 1,004 men) developed cancer during 9 years of follow-up. In women, after adjustment for potential confounders, the RR of all cancers associated with different BMI, relative to a BMI of 18.5–24.9, were 1.04 (95% CI = 0.85–1.27) for BMI = 25.0–27.4, 1.29 (1.00–1.68) for BMI = 27.5–29.9 and 1.47 (1.06–2.05) for BMI ≥30.0 (p for trend = 0.007). Higher BMI was also significantly associated with higher risk of cancers of the colorectum, breast (postmenopausal), endometrium and gallbladder in women. In men, we observed significantly increased all-cancer risk among only never-smokers. Overweight and obesity could account for 4.5% (all subjects) or 6.2% (never-smokers) of the risk of any cancer in women and −0.2% (all subjects) or 3.7% (never-smokers) in men. The value for women was within the range among women reported from Western populations (3.2%–8.8%). Our data demonstrate that excess weight is a major cancer risk among Japanese women.