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.

Background: Acrylamide has been classified as a probable human carcinogen based chiefly on laboratory evidence. However, the influence of dietary acrylamide intake on risk of esophageal, gastric, and colorectal cancer has not been extensively studied. We aimed to evaluate the association between dietary acrylamide intake and esophageal, gastric, and colorectal cancer using data from the Japan Public Health Center–based Prospective Study. Methods: Our study included 87,628 participants who completed a food-frequency questionnaire at enrollment in 1990 and 1993. We used Cox proportional hazards regression models to estimate hazards ratios and 95% confidence intervals (CI) after adjusting for confounding factors. Results: After 15.5, 15.3, and 15.3 mean years of follow-up for esophageal, gastric, and colorectal cancer, we identified and analyzed 391 esophageal, 2,218 gastric, and 2,470 colorectal cancer cases, respectively. Compared with the lowest quintile of acrylamide intake, the multivariate HR for the highest quintile was 0.86 (95% CI, 0.53–1.39; Ptrend = 0.814), 0.84 (95% CI, 0.69–1.01; Ptrend = 0.301), and 0.93 (95% CI, 0.79–1.08; Ptrend = 0.165) for esophageal, gastric, and colorectal cancer, respectively, in the multivariable-adjusted model. Furthermore, no significant associations were observed when the participants were stratified by cancer subsites. Conclusions: In conclusion, this study demonstrated that dietary acrylamide intake was not associated with increased risk of esophageal, gastric, or colorectal cancer among the Japanese population. Impact: It is the first time to assess the effect of dietary acrylamide intake on risk of digestive system cancer in Asian populations.

A meta‐analysis published in 2015 noted a marginally increased risk of endometrial and ovarian cancers in non‐smoking women with dietary acrylamide intake, but only a few studies were included, and they were limited to Western countries. The aim of this study was to investigate the association between dietary acrylamide intake and endometrial or ovarian cancer risk in the Japan Public Health Center‐based Prospective Study (JPHC Study). In this prospective cohort study, 47 185 participants aged 45‐74 years at the follow‐up starting point in the JPHC Study were enrolled. Dietary acrylamide intake was assessed using a validated food frequency questionnaire. Cox proportional hazards regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (95%CI). In participants with endometrial and ovarian cancer, the average follow‐up periods were 15.5 and 15.6 years, respectively, and 161 and 122 cases of endometrial and ovarian cancer were diagnosed, respectively. Energy‐adjusted dietary acrylamide intake was negatively associated with endometrial cancer, but the association disappeared after adjusting for coffee consumption with an adjusted HR for the highest vs lowest tertile of 0.85 (95%CI: 0.54‐1.33). No association was observed, however, for ovarian cancer (adjusted HR, 0.77; 95%CI: 0.49‐1.23). Furthermore, after stratifying by smoking status, coffee consumption, alcohol consumption, body mass index, and menopause status, no association was observed. Dietary acrylamide intake was not associated with the risk of endometrial or ovarian cancer in Japanese women with a relatively lower dietary intake of acrylamide compared with Western populations.

Background: Acrylamide, a probable carcinogen to humans, forms during high temperature cooking. Dietary exposure to acrylamide among the Japanese population is unknown. We aimed to establish and validate a method to assess acrylamide exposure among the Japanese population using a food frequency questionnaire (FFQ) from the Japan Public Health Center-based prospective study.Methods: Validation studies for the FFQ were conducted in 1994 (Cohort I, n = 215) and 1996 (Cohort II, n = 350). The 28-day dietary records (DRs) were collected over 1 year. The FFQ was distributed before and after DR collection. Data for acrylamide exposure were based on reported measurements in Japan, and calculations considered the cooking process for specific vegetables in a home setting. Spearman’s rank correlation and weighted kappa coefficients were calculated from energy-adjusted data.Results: Mean acrylamide intake levels estimated from DRs for Cohorts I and II were 6.78 (standard deviation [SD], 3.89) µg/day and 7.25 (SD, 3.33) µg/day, and corresponding levels estimated from the FFQ were 7.03 (SD, 4.30) µg/day and 7.14 (SD, 3.38) µg/day, respectively. Deattenuated correlation coefficients for men and women were 0.54 and 0.48 in Cohort I and 0.40 and 0.37 in Cohort II, respectively. Weighted kappa coefficients were over 0.80 in all cases. The main contributing food groups from DRs were beverages, confectioneries, vegetables, potatoes and starches, and cereals.Conclusions: High kappa values validate the use of FFQ in epidemiological studies. The marked contribution of cooked vegetables indicates the importance of considering household cooking methods in assessing acrylamide intake levels in the Japanese population.