Combined impact of five lifestyle factors and subsequent risk of cancer: The Japan Public Health Center Study

Objective. To evaluate whether 5 combined healthy lifestyle factors (not smoking, moderate drinking, eating minimum salt-preserved foods, being physically active, and having appropriate body mass index) are associated with reduced risk of cancer. Methods. Participants were enrolled in the Japan Public Health Center Study and responded to the 5-year follow-up questionnaire covering lifestyle factors in 1995-1999 at ages 45-74 years. During follow up through December 31, 2006, 3451 and 2125 cases of cancer were newly identified in men and women, respectively. For men and women, a factor-dependent risk reduction was observed for healthy lifestyles and cancer development Compared to 0-1 healthy lifestyle factors, the adjusted RRs and 95% Cls for adherence to 2, 3, 4, and 5 healthy factors were 0.86 (0.78-0.95), 0.72 (0.65-0.80), 0.61 (0.54-0.69). and 0.57 (0.45-0.72), respectively, for men (P for trend <0.0001) and 0.86 (0.53-1.40), 0.73 (0.46-1.16), 0.68 (0.42-1.08), and 0.63 (0.39-1.01), respectively, for women (P for trend = 0.0003). Risk was reduced 14% and 9% by each one healthy lifestyle for men and women, respectively. Risk reduction was more pronounced among elderly women. Conclusion. These combined lifestyle factors have a considerable impact on preventing cancer. (C) 2011 Elsevier Inc. All rights reserved.