Reproducibility and dietary correlates of plasma polyphenols in the JPHC-NEXT Protocol Area study.

BACKGROUND: In recent years, an increasing number of epidemiological studies have suggested a role of polyphenols in the prevention of chronic diseases. Prospective cohort studies have typically measured polyphenol concentrations in a single blood sample and the reproducibility of plasma polyphenol measurements is largely unknown. OBJECTIVE: We evaluated the reproducibility of 35 plasma polyphenols collected at an interval of 1-year. We also examined correlations of these polyphenols with food group intakes calculated from weighed food records (WFR) and food frequency questionnaire (FFQ). METHODS: The study included 227 middle-aged participants from the JPHC-NEXT Protocol Area in Japan. We measured 35 polyphenols in plasma collected at two points 1-year apart. Food group intakes were calculated from 12-day WFR and FFQ. For the reproducibility analysis, the intraclass correlation coefficient (ICC) of 35 polyphenol concentrations were examined between the two points. Pearson's partial correlations was used to assess the correlation between polyphenols and food groups. RESULTS: Moderate- to high ICCs were observed for tea-originated polyphenols such as gallic acid, quercetin, epigallocatechin, and kaempferol - and coffee-derived polyphenols, such as caffeic acid, and ferulic acid. For the dietary analyses, moderate correlations were observed for non-alcoholic beverages intake and epigallocatechin, epicatechin, catechin, and gallic acid. For green tea, higher correlations were observed with these polyphenols. CONCLUSION: Plasma concentrations of tea and coffee-related polyphenols, except for catechin, had good reproducibility over a 1-year period. The correlations between intake of non-alcoholic beverages, particularly green tea, and tea polyphenols, indicated moderate- to high correlations.

Economic burden of cancer attributable to modifiable risk factors in Japan.

Controlling avoidable causes of cancer may save cancer-related healthcare costs and indirect costs of premature deaths and productivity loss. This study aimed to estimate the economic burden of cancer attributable to major lifestyle and environmental risk factors in Japan in 2015. We evaluated the economic cost of cancer attributable to modifiable risk factors from a societal perspective. We obtained the direct medical costs for 2015 from the National Database of Health Insurance Claims and Specific Health Checkups of Japan, and estimated the indirect costs of premature mortality and of morbidity due to cancer using the relevant national surveys in Japan. Finally, we estimated the economic cost of cancer associated with lifestyle and environmental risk factors. The estimated cost of cancer attributable to lifestyle and environmental factors was 1,024,006 million Japanese yen (¥) (8,460 million US dollars [$]) for both sexes, and ¥673,780 million ($5,566 million) in men and ¥350,226 million ($2,893 million) in women, using the average exchange rate in 2015 ($1 = ¥121.044). A total of ¥285,150 million ($2,356 million) was lost due to premature death in Japan in 2015. Indirect morbidity costs that could have been prevented were estimated to be ¥200,602 million ($1,657 million). Productivity loss was highest for stomach cancer in men (¥28,735 million/$237 million) and cervical cancer in women (¥24,448 million/$202 million). Preventing and controlling cancers caused by infections including Helicobacter pylori, human papillomavirus and tobacco smoking will not only be life-saving but may also be cost-saving in the long run.

Dietary Consumption of Antioxidant Vitamins in Relation to Prostate Cancer Risk in Japanese Men: The Japan Public Health Center-Based Prospective Study.

BACKGROUND: Many epidemiological studies have investigated dietary intake of antioxidant vitamins in relation to prostate cancer risk in Western countries, but the results are inconsistent. However, few studies have reported this relationship in Asian countries. METHODS: We investigated the association between intake of vitamins, including lycopene, α-carotene, ß-carotene, vitamin C, vitamin E, with prostate cancer risk in the Japan Public Health Center-based Prospective (JPHC) study. 40,720 men without history of cancer finished the food frequency questionnaire (FFQ) and were included in the study. Hazard ratios (HRs) and 95% confidence intervals (CIs) of prostate cancer risk were calculated according to the quintiles of energy-adjusted intake of vitamins using Cox models. RESULTS: After an average of 15.2 years (617,599 person-years in total) of follow-up, 1,386 cases of prostate cancer were identified, including 944 localized cases and 340 advanced cases. No associations were observed in consumption of antioxidant vitamins, including α-carotene, ß-carotene, vitamin C, and vitamin E, and prostate cancer risk. Although higher lycopene intake was associated with increased risk of prostate cancer (HR for the highest versus the lowest, 1.24; 95% CI, 1.04-1.47; P for trend=0.01), there was a null association of lycopene intake with risk of prostate cancer detected by subjective symptoms (HR, 1.12; 95% CI, 0.79-1.58; P for trend=0.11). CONCLUSIONS: Our study suggested no association between antioxidant intake of vitamins and prostate cancer risk.

Associations between dairy intake and mortality due to all-cause and cardiovascular disease: the Japan Public Health Center-based prospective study.

BACKGROUND: Some studies have investigated the relation between dairy products and mortality, but with inconsistent results. OBJECTIVE: We examined the association between the consumption of dairy products and the risk of all-cause, cancer-related, and cardiovascular disease (CVD)-related mortality. METHODS: From the Japan Public Health Center-based Prospective (JPHC) study, 43,117 males and 50,193 females with no history of cancer or CVD finished the food frequency questionnaire (FFQ) and were included in the study. Intake of dairy products was assessed using the FFQ and adjusted for total energy by using the residual method. We used multivariate Cox proportional hazard models to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for mortality risk in males and females. RESULTS: 14,211 deaths in males and 9547 deaths in females from all causes were identified during an average follow-up of 19.3 years. For males, total dairy consumption was nonlinearly and significantly associated with lower risk of mortality from all causes [the third quartile, HR = 0.87 (0.83, 0.91), the fourth quartile, HR = 0.89 (0.85, 0.94), P for nonlinearity < 0.001] and CVD [the third quartile, HR = 0.77 (0.70, 0.85), the fourth quartile, HR = 0.78 (0.70, 0.86), P for nonlinearity < 0.001]. Milk and fermented milk intake were inversely associated with all-cause and CVD-related mortality in males. Cheese consumption was inversely associated with CVD-related mortality among males. There was no association between total dairy intake and mortality risk among females. CONCLUSION: For Japanese people, consumption of dairy products was associated with a decreased risk of mortality from all-cause and cardiovascular diseases among males.

Prospective study of dietary changes in cancer survivors for five years including pre- and post- diagnosis compared with those in cancer-free participants.

The number of long-term survivors after a cancer diagnosis is increasing. Few investigations have compared survivors' diets to their original pre-diagnosis dietary pattern or with the patterns of cancer-free controls. We examined the dietary changes in survivors for five years (i.e. before to after diagnosis) in cancer survivors, comparing them with cancer-free controls in a prospective cohort study in Japan. Using 1995-1998 for the baseline and 2000-2003 for the follow-up survey, a validated food frequency questionnaire was administered to 33,643 men and 39,549 women aged 45-74 years. During the follow-up period, 886 men and 646 women had developed cancer. Participants that had not been diagnosed with cancer served as controls. There was a greater decrease in the calorie intake (median change: - 168 kcal/d [Interquartile range: - 640, 278]) in male cancer survivors compared to controls (- 33 kcal/d [- 453, 380], P < .001). On comparison with cancer-free controls, multiple linear regression analysis revealed a significantly larger reduction in energy-adjusted ethanol intake for male cancer survivors (ß = - 0.36). There was no difference in changes in fruit and vegetable or red meat intake and no other significant differences in dietary changes between survivors and controls for either gender. This suggests that most dietary changes in survivors after cancer diagnosis are not systematically different from those that occur in people without a cancer diagnosis.

Acrylamide and Glycidamide Hemoglobin Adduct Levels and Breast Cancer Risk in Japanese Women: A Nested Case-Control Study in the JPHC.

BACKGROUND: Acrylamide (AA) is classified as "probably carcinogenic to humans (class 2A)" by the International Agency for Research on Cancer. AA causes cancer owing to its mutagenic and genotoxic metabolite, glycidamide (GA), and its effects on sex hormones. Both AA and GA can interact with hemoglobin to hemoglobin adducts (HbAA and HbGA, respectively), which are considered appropriate biomarkers of internal exposure of AA. However, few epidemiologic studies reported an association of HbAA and HbGA with breast cancer. METHODS: We conducted a nested case-control study within the Japan Public Health Center-based Prospective Study cohort (125 cases and 250 controls). Cases and controls were categorized into tertiles (lowest, middle, and highest) using the distribution of HbAA or HbGA levels in the control group and estimated ORs and 95% confidence intervals (CI) using conditional logistic regression, adjusting for potential confounders. RESULTS: No association was observed between HbAA (ORHighestvs.Lowest, 1.34; 95% CI, 0.69-2.59), HbGA (ORHighest vs. Lowest, 1.46; 95% CI, 0.79-2.69), their sum HbAA+HbGA (ORHighest vs. Lowest, 1.36; 95% CI, 0.72-2.58) and breast cancer; however, some evidence of positive association was observed between their ratio, HbGA/HbAA, and breast cancer (ORHighest vs. Lowest, 2.19; 95% CI, 1.11-4.31). CONCLUSIONS: There was no association between biomarkers of AA and breast cancer. IMPACT: It is unlikely that AA increases breast cancer risk; however, the association of AA with breast cancer may need to be evaluated, with a focus not only on the absolute amount of HbAA or HbGA but also on HbGA/HbAA and the activity of metabolic genes.

Inverse Association between Fruit and Vegetable Intake and All-Cause Mortality: Japan Public Health Center-Based Prospective Study.

BACKGROUND: A dose-response and nonlinear association between fruit and vegetable intake and mortality has been reported in Europe and the United States, but little is known about this association in Asia. OBJECTIVES: This study aimed to evaluate the association of fruit and vegetable intake with all-cause, cancer, cardiovascular, and respiratory disease mortality in a Japanese cohort. METHODS: In the Japan Public Health Center-based prospective study, we included 94,658 participants (mean age: 56.4; 46.0% male) without cancer and cardiovascular disease at baseline. Information on fruit and vegetable intake was collected using a validated FFQ. The Cox proportional hazard model was used to estimate HRs and 95% CIs of each quintile of fruit and vegetable intake, separately, in relation to all-cause and cause-specific mortality using the first quintile as a reference. Nonlinear associations were evaluated using a likelihood ratio test, comparing a linear model with a restricted cubic spline model. RESULTS: During a median of 20.9 follow-up years (IQR: 19.6-23.8 y), 23,687 all-cause deaths were documented. After adjusting for age, sex, and potential confounding factors, fruit and vegetable intake was nonlinearly and significantly associated with lower all-cause mortality, with the fourth and fifth quintiles having comparable HRs (fruit: fourth quintile HR: 0.91; 95% CI: 0.87, 0.95 and fifth quintile HR: 0.92; 95% CI: 0.88, 0.96; P-nonlinearity < 0.001; vegetable: fourth quintile HR: 0.92; 95% CI: 0.88, 0.97 and fifth quintile HR: 0.93; 95% CI: 0.89, 0.98; P-nonlinearity = 0.002). Fruit intake was significantly associated with lower cardiovascular mortality (HR in the fifth quintile: 0.91; 95% CI: 0.83, 0.99; P-nonlinearity = 0.01). CONCLUSIONS: In the Japanese population, higher intake of fruits and vegetables was nonlinearly associated with decreased all-cause mortality. These findings may contribute to the establishment of dietary recommendations for enhancing life expectancy in Asia.

Dietary fibre intake is associated with reduced risk of lung cancer: a Japan public health centre-based prospective study (JPHC).

BACKGROUND: Several epidemiological studies have been conducted to draw consistent conclusions regarding the effect of dietary fibre on lung diseases and lung cancer. However, the effect of dietary fibre on the incidence of lung cancer remains unclear in an Asian population. METHODS: We investigated the association between the intake of total dietary fibre and dietary fibre from different food sources and lung cancer incidence in a Japan public health centre-based prospective study (JPHC). A total of 73 405 participants (33 012 men and 40 393 women) aged 45-74 years were eligible for our study. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: During a median follow-up of 18.0 years, 1546 (1042 men and 504 women) newly diagnosed cases of lung cancer were ascertained. In the multivariable models, total dietary fibre intake was inversely associated with lung cancer risk in men, the HRs Q5 vs Q1 (95% CI) were 0.77 (0.62 to 0.94), P-trend = 0.020. Dietary fibre intake from vegetables was protectively associated with lung cancer risk in men [HR Q5 vs Q1 (95% CI): 0.80 (0.64 to 0.99), P-trend = 0.053]. However, no such association was observed in women. CONCLUSIONS: In men, a high intake of total dietary fibre may have preventive benefits for lung cancer incidence: dietary fibre intake from vegetables was associated with a lower incidence of lung cancer. However, similar associations did not appear in women. Further investigations are required to confirm the association between dietary fibre and lung cancer risk in women.

Burden of cancer attributable to modifiable factors in Japan in 2015.

The This study estimated the cancer burden attributable to modifiable factors in Japan in 2015 using the best available epidemiological evidence and a standard methodology. We selected the following factors for inclusion in the estimates, namely tobacco smoking (active smoking and secondhand smoking), alcohol drinking, excess bodyweight, physical inactivity, infectious agents (Helicobacter pylori, hepatitis C virus, hepatitis B virus, human papilloma virus, Epstein-Barr virus, and human T-cell leukemia virus type 1), dietary intake (highly salted food, fruit, vegetables, dietary fiber, red meat, processed meat), exogenous hormone use, never breastfeeding and air pollution, given that these were considered modifiable, in theory at least. We first estimated the population attributable fraction (PAF) of each cancer attributable to these factors using representative relative risks of Japanese and the prevalence of exposures in Japanese around 2005, in consideration of the 10-year interval between exposure and cancer outcomes. Using nationwide cancer incidence and mortality statistics, we then estimated the attributable cancer incidence and mortality in 2015. We finally obtained the PAF for site-specific and total cancers attributable to all modifiable risk factors using this formula, with statistical consideration of the effect of overlap between risk factors. The results showed that 35.9% of all cancer incidence (43.4% in men and 25.3% in women) and 41.0% of all cancer mortality (49.7% in men and 26.8% in women) would be considered preventable by avoidance of these exposures. Infections and active smoking followed by alcohol drinking were the greatest contributing factors to cancer in Japan in 2015.

Low-carbohydrate diet and risk of cancer incidence: The Japan Public Health Center-based prospective study.

Epidemiological evidence on the effects of a long-term low-carbohydrate diet (LCD) on cancer incidence remains sparse. We investigate the association between LCD and the risk of overall and specific cancer site incidence in a Japanese population-based prospective cohort study among 90 171 participants aged 45-74. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During a median 17.0 y of follow-up, we identified 15 203 cancer cases. A higher overall LCD score was associated with increased overall cancer risk (HR = 1.08 [CI: 1.02-1.14], P-trend = .012), while it was associated with decreased gastric cancer (GC) risk (0.81 [0.71-0.93], P-trend = .006). A higher animal-based LCD score was associated with higher risk of overall cancer (1.08 [1.02-1.14], P-trend = .003), colorectal cancer (CRC) (1.11 [0.98-1.25], P-trend = .018), rectal cancer (RC) (1.24 [1.00-1.54], P-trend = .025), lung cancer (LC) (1.16 [1.00-1.34], P-trend = .042), and lower risk of GC (0.90 [0.79-1.01], P-trend = .033). Furthermore, we found that plant-based LCD score was related to lower GC incidence (0.87 [0.77-0.99], P-trend = .031). Additionally, adjusted for plant fat intake amplified the adverse associations (overall cancer: 1.08 [1.02-1.14] vs. 1.11 [1.05-1.18]; CRC: 1.08 [0.95-1.22] vs. 1.13 [0.99-1.30]; LC: 1.14 [0.98-1.33] vs. 1.19 [1.01-1.41]). We conclude that LCD enriching with animal products was associated with increased overall cancer, CRC, and LC incidence. These adverse associations could be attenuated by plant fat consumption. LCD reduces the risk of developing GC. Long-term adherence to LCD without paying attention to the balance between animal and plant food source consumption might cause adverse overall cancer incidence consequences.

Sugary drink consumption and risk of kidney and bladder cancer in Japanese adults.

Globally, sugary drinks are widely consumed, however, few epidemiologic studies have investigated the association between sugary drink consumption and risk of kidney and bladder cancer. We examined the association of sugary drinks with risk of kidney and bladder cancer in 73,024 participants from the Japan Public Health Center-based Prospective Study who reported no history of cancer. Sugary drink consumption was assessed using a validated food frequency questionnaire at study baseline (1995-1999). Individuals were followed to December 31, 2013. Multivariable Cox proportional hazards regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CIs). During 1,069,815 person years of follow-up, 169 kidney cancer and 297 bladder cancer cases were documented. After adjusting for potential confounders, no greater risk of kidney and bladder cancer was observed. However, sugary drink consumption was positively associated with the risk of kidney cancer (HR for 100 ml/day increase in consumption was 1.11 [95% CI 1.01-1.22]) and bladder cancer (HR for 100 ml/d increase in consumption was 1.11 [95% CI 1.01-1.22]) among women after exclusion of cases diagnosed in the first three years of follow-up. In this large prospective cohort, consumption of sugary drinks was significantly associated with a small increase in hazard ratio for kidney and bladder cancer among women after exclusion of cases diagnosed within the first three years.

Validity of a food frequency questionnaire for the estimation of total polyphenol intake estimates and its major food sources in the Japanese population: the JPHC FFQ Validation Study.

We examine the validity and reproducibility of a food frequency questionnaire (FFQ) in a subsample of participants in the Japan Public Health Center-based Prospective Cohort Study using a database of polyphenol-containing foods commonly consumed in the Japanese population. Participants of the validation study were recruited from two different cohorts. In Cohort I, 215 participants completed a 28-d dietary record (DR) and the FFQ, and in Cohort II, 350 participants completed DRs and the FFQ. The total polyphenol intake estimated from the 28-d DR and FFQ were log-transformed and adjusted for energy intake by the residual method. Spearman correlation coefficients (CCs) between estimates from the FFQ and 28-d DR as well as two FFQs administered at a 1-year interval were computed. Median intakes of dietary polyphenols calculated from the DRs were 1172 mg/d for men and 1024 mg/d for women in Cohort I, and 1061 mg/d for men and 942 mg/d for women in Cohort II. The de-attenuated CCs for polyphenol intake between the DR and FFQ were 0⋅47 for men and 0⋅37 for women in Cohort I and 0⋅44 for men and 0⋅50 for women in Cohort II. Non-alcoholic beverages were the main contributor to total polyphenol intake in both men and women, accounting for 50 % of total polyphenol intake regardless of cohort and gender, followed by alcoholic beverages and seasoning and spices in men, and seasoning and spices, fruits and other vegetables in women. The present study showed that this FFQ had moderate validity and reproducibility and is suitable for use in future epidemiological studies.

Dietary glycemic index, glycemic load and mortality: Japan Public Health Center-based prospective study.

PURPOSE: Long-term associations of dietary glycemic index (GI) and glycemic load (GL) with mortality outcomes remain unclear. METHODS: The present analysis included 72,783 participants of the Japan Public Health Center-based Prospective Study. Participants who responded to the 5-year follow-up questionnaire in 1995-1999 were followed-up until December 2015. We estimated the risk of total and cause-specific mortality associated with GI and GL using Cox proportional hazards regression models. RESULTS: During 1,244,553 person years of follow-up, 7535 men and 4913 women died. GI was positively associated with all-cause mortality. As compared with the lowest quartile, the multivariable HR for those who had the highest quartile of GI was 1.14 (95% CI 1.08-1.20). The HRs for death comparing the highest with the lowest quartile were 1.28 (95% CI 1.14-1.42) for circulatory system diseases, 1.33 (95% CI 1.14-1.55) for heart disease, 1.32 (95% CI 1.11-1.57) for cerebrovascular disease, and 1.45 (95% CI 1.18-1.78) for respiratory diseases. GI was not associated with mortality risks of cancer and digestive diseases. GL showed a null association with all-cause mortality (highest vs lowest quartile; HR 1.04; 95% CI 0.96-1.12). However, among those who had the highest quartile of GL, the HRs for death from circulatory system diseases was 1.24 (95% CI 1.05-1.46), cerebrovascular disease was 1.34 (95% CI 1.03-1.74), and respiratory diseases was 1.35 (95% CI 1.00-1.82), as compared with the lowest quartile. CONCLUSION: In this large prospective cohort study, dietary GI and GL were associated with mortality risks.

Dietary Inflammatory Index Is Associated With Inflammation in Japanese Men.

Background: Dietary components are known to affect chronic low-grade inflammation status. The dietary inflammatory index (DII®) was developed to measure the potential impact of a diet on an individual's inflammatory status, and it has been validated mainly in Western countries. Objective: This study aimed to examine the validity of the energy-adjusted DII (E-DIITM) using high-sensitivity C-reactive protein (hs-CRP) concentration in Japanese men and women. Methods: In total, 6,474 volunteers from a cancer-screening program (3,825 men and 2,649 women) completed a food frequency questionnaire (FFQ) and their hs-CRP concentrations were evaluated. E-DII scores were calculated on the basis of 30 food parameters derived from the FFQ. Higher E-DII scores reflect a greater pro-inflammatory potential of the diet. The associations between E-DII quartiles and hs-CRP concentration were assessed using regression models adjusted for age, body mass index, smoking status, and amount of physical activity. Results: Mean E-DII in men and women was + 0.62 ± 1.93 and -1.01 ± 2.25, respectively. The proportion of men and women who had hs-CRP concentration >3 mg/L was 4.7 and 3.1%, respectively. A significant positive association was observed between E-DII score and hs-CRP concentration in men; geometric mean of hs-CRP concentration in the lowest and highest E-DII quartiles was 0.56 mg/L and 0.67 mg/L (P trend < 0.01), respectively. The odds ratio (95% confidence interval) of having an elevated hs-CRP concentration (>3 mg/L) was 1.72 (1.10-2.67) in the highest E-DII quartile (P trend = 0.03) in men. However, no association was observed between E-DII score and hs-CRP concentration in women, except in those not taking prescription medications. Conclusions: DII was associated with inflammation status in Japanese men, but the association was limited in Japanese women.

Dietary Acrylamide Intake and the Risk of Hematological Malignancies: The Japan Public Health Center-Based Prospective Study.

Acrylamide, which is present in many daily foods, is a probable human carcinogen. In 2002, it was identified in several common foods. Subsequently, western epidemiologists began to explore the relationship between dietary acrylamide exposure and cancer risk; however, limited suggestive associations were found. This prospective study aimed to examine the association between dietary acrylamide intake and the risk of hematological malignancies, including malignant lymphoma (ML), multiple myeloma (MM), and leukemia. We enrolled 85,303 participants in the Japan Public Health Center-based Prospective study on diet and cancer as from 1995. A food frequency questionnaire that included data on acrylamide in all Japanese foods was used to assess dietary acrylamide intake. We applied multivariable adjusted Cox proportional hazards models to reckon hazard ratios (HRs) for acrylamide intake for both categorical variables (tertiles) and continuous variables. After 16.0 median years of follow-up, 326 confirmed cases of ML, 126 cases of MM, and 224 cases of leukemia were available for final multivariable-adjusted analysis. HRs were 0.87 (95% confidence interval [CI]: 0.64-1.18) for ML, 0.64 (95% CI: 0.38-1.05) for MM, and 1.01 (95% CI: 0.71-1.45) for leukemia. Our results implied that acrylamide may not be related to the risk of hematological malignancies.

Dietary Acrylamide Intake and the Risks of Renal Cell, Prostate, and Bladder Cancers: A Japan Public Health Center-Based Prospective Study.

Acrylamide can be carcinogenic to humans. However, the association between the acrylamide and the risks of renal cell, prostate, and bladder cancers in Asians has not been assessed. We aimed to investigate this association in the Japan Public Health Center-based Prospective Study data in 88,818 Japanese people (41,534 men and 47,284 women) who completed a food frequency questionnaire in the five-year follow-up survey in 1995 and 1998. A validated food frequency questionnaire was used to assess the dietary acrylamide intake. Cox proportional hazard regression models were used to estimate hazard ratios and 95% confidence intervals (CIs). During a mean follow-up of 15.5 years (15.2 years of prostate cancer), 208 renal cell cancers, 1195 prostate cancers, and 392 bladder cancers were diagnosed. Compared to the lowest quintile of acrylamide intake, the multivariate hazard ratios for the highest quintile were 0.71 (95% CI: 0.38-1.34, p for trend = 0.294), 0.96 (95% CI: 0.75-1.22, p for trend = 0.726), and 0.87 (95% CI: 0.59-1.29, p for trend = 0.491) for renal cell, prostate, and bladder cancers, respectively, in the multivariate-adjusted model. No significant associations were observed in the stratified analyses based on smoking. Dietary acrylamide intake was not associated with the risk of renal cell, prostate, and bladder cancers.

Sugary Drink Consumption and Subsequent Colorectal Cancer Risk: The Japan Public Health Center-Based Prospective Cohort Study.

BACKGROUND: Most studies examining the associations of sugary drink consumption on colorectal cancer risk have been conducted in Western populations. METHODS: This study consisted of 74,070 participants in the Japan Public Health Center-based Prospective Study who completed a food frequency questionnaire (1995-1999). The participants were followed until December 2013 to investigate the associations between sugary drink consumption and colorectal cancer risk using Cox proportional hazards regression models. RESULTS: Among the 74,070 participants, mean age was 56.5 years at baseline, with a mean body mass index (BMI) of 23.5 and a mean daily consumption of 286 mL/day for men and 145 mL/day for women. During a follow-up of 15 years, 1,648 colorectal cancer cases were identified. No overall greater risk of colorectal cancer was observed among men [multivariable HR = 0.84; 95% confidence of interval (CI), 0.70-1.02; ≥254 mL/day vs. nonconsumers] and women (HR = 1.20; 95% CI, 0.96-1.50, ≥134 mL/day vs. nonconsumers). Sugary drink consumption was associated with colon cancer among women (HR = 1.36; 95% CI, 1.03-1.78, ≥134 mL/day vs. nonconsumers). HRs for proximal colon cancer among women who consumed sugary drinks, as compared with nonconsumers, were 1.47 (95% CI, 1.03-2.10) for sugary drink consumption less than 134 mL/day, and 1.45 (95% CI, 1.01-2.09) for at least 134 mL/day. CONCLUSIONS: In this large prospective cohort of Japanese with a moderate sugary drink consumption level and low prevalence of obesity, we observed a 36% increased risk of colon cancer in women. IMPACT: Our findings highlight the importance of subsite- and sex-specific investigation.

Comparison between the impact of fermented and unfermented soy intake on the risk of liver cancer: the JPHC Study.

PURPOSE: The aim of this study was to compare the impact of fermented and unfermented soy intake, based on the following soy-derived products: tofu, soymilk, natto, and miso, on the risk of liver cancer among Japanese adults. METHODS: 75,089 Participants of the Japan Public Health Center-based Prospective Study (JPHC Study) were followed from the time of the 5-year follow-up questionnaire until the end of 2012-2013. Subjects with available data on hepatitis B virus (HBV) and hepatitis C virus (HCV) infection status from blood samples (n = 14,016) and those who were anti-HCV antibody (anti-HCV) or hepatitis B virus antigen (HBsAg) positive (n = 1033) were also analyzed separately. Cox proportional hazard models were employed to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs). RESULTS: During 1,145,453 person-years, 534 newly diagnosed cases of liver cancer were identified in the JPHC Study. For miso intake among men, the multivariate-adjusted highest versus lowest quartile HR was 0.65 (95% CI, 0.48-0.89); p for trend = 0.006. Results were similar in those who were anti-HCV or HBsAg positive, 0.24 (0.08-0.70); p for trend = 0.004 highest versus lowest tertile. For the sub-analysis among only participants with known hepatitis infection status and HCV and HBsAg adjustment, a similar association was observed. In the multivariate complete cohort analysis, among women, the highest intake of fried tofu was inversely associated with the risk of liver cancer, HR = 0.45 (0.26-0.80); p for trend = 0.014. CONCLUSIONS: We observed no association between total soy intake, fermented and unfermented, and risk of liver cancer, and only an inverse association between miso intake and liver cancer among men.

Fermented and nonfermented soy foods and the risk of breast cancer in a Japanese population-based cohort study.

BACKGROUND: Although preclinical studies suggest that fermented soy foods may have a protective effect against breast cancer, no prospective cohort studies have examined this association. OBJECTIVE: Our study examined the association between fermented and nonfermented soy food intake and breast cancer risk using a population-based prospective cohort study in Japan. METHODS: We included a total of 47,614 women aged 45-74 years in an analysis of the Japan Public Health Center-based Prospective Study (JPHC Study). A validated food frequency questionnaire (FFQ) was used for the assessment of dietary intake. Breast cancer incidence was analyzed by multivariate Cox proportional hazards regression models. RESULTS: During an average of 15.5 years of follow-up, 825 breast cancer cases were newly identified. We found no association of intake of soy foods with breast cancer risk, regardless of fermentation, with multivariate hazard ratios (HRs) and 95% confidence intervals (CIs) for the highest quartiles of fermented and nonfermented soy food intake of 0.94 (0.67, 1.32) and 1.15 (0.85, 1.57) compared with the lowest quartile (p for trend = 0.305 and 0.393). Unlike nonfermented soy, higher intake of fermented soy foods was associated with a significant decrease in the risk of nonlocalized breast cancer. The HR and 95% CI in the highest compared to lowest intake category of fermented soy foods was 0.53 (0.28, 0.99) versus nonfermented soy foods 0.85 (0.51, 1.42) (p for trend = 0.026 and 0.797). CONCLUSIONS: Our analyses showed that fermented soy foods had no association with overall breast cancer but may be associated with decreased risk of nonlocalized breast cancer.