Dietary acrylamide intake and risk of breast cancer: The Japan Public Health Center-based Prospective Study.

Acrylamide forms during cooking and is classified as a probable carcinogen in humans, mandating the need for epidemiological studies of dietary acrylamide and cancers. However, the risk of dietary acrylamide exposure to breast cancer in Japanese women has not been assessed. We investigated the association between dietary acrylamide intake and risk of breast cancer in the Japan Public Health Center-based Prospective Study. The present study included 48 910 women aged 45-74 years who responded to a 5-year follow-up survey questionnaire. Dietary acrylamide intake was assessed using a validated food frequency questionnaire. Cox proportional hazards regression models were used to estimate hazard ratios and 95% confidence intervals. During an average of 15.4 years of follow up, 792 breast cancers were diagnosed. Energy-adjusted dietary acrylamide intake was not associated with the risk of breast cancer (adjusted hazard ratio for highest versus lowest tertile = .95, 95% confidence intervals: 0.79-1.14, P-trend = .58). Further, no significant associations were observed when stratified analyses were conducted by smoking status, coffee consumption, alcohol consumption, body mass index, menopausal status, estrogen receptor status, and progesterone receptor status. In conclusion, dietary acrylamide intake was not associated with the risk of breast cancer in this population-based prospective cohort study of Japanese women.