BACKGROUND:Although the presence or absence of cardiovascular disease (CVD) recurrence is related to lifestyle habits, including diet, evidence for the maintenance of dietary improvement among participants with incident CVD after acute treatment is scarce. AIM:To determine changes in diet and other lifestyle factors in participants with incident CVD in the Japan Public Health Center-based Prospective Study (JPHC study) over a 5-year period before and after diagnosis by comparing changes with those in participants without a diagnosis of CVD. METHODS:Participants were 68733 subjects aged 45-76 years at the baseline survey. Intakes of seven nutrients and 16 food groups were estimated using Food Frequency Questionnaires at the baseline survey and 5-year follow-up survey, and the amount of change was determined. Those diagnosed with CVD during the 5-year follow-up period were defined as participants with incident CVD (800 cases) and those not diagnosed were considered the non-CVD controls. Differences in the change between the two groups over the 5-year period were examined using the Mann-Whitney U test and multivariate linear regression analysis. Changes in smoking status, body mass index (BMI), and physical activity were compared by logistic regression analysis. RESULTS:CVD participants appeared to restrict sodium intake after diagnosis, and even after energy adjustment were more likely to avoid eating sodium, miso soup and pickles. In addition, they were less likely to eat beef and pork than controls. Significantly more CVD participants than controls stopped smoking and had decreased BMI. CONCLUSION:Participants with incident CVD showed modification in selective lifestyle factors, characterised by reduced sodium intake and smoking cessation.

Background/Objectives: Existing methods for assessing the intake of vegetables and fruits have limitations. This study aims to investigate the number of measurements required to screen individuals with insufficient usual vegetable intake or total fruit and vegetable intake using urinary potassium excretion estimated from spot urine samples, a non-invasive and simple biomarker. Methods: A total of 97 women aged 18-24 years provided a 12-day dietary survey, four 24 h urine collections, and three timed spot urine samples per day, collected in a duration of 4 days. Using the dietary surveys as a reference, we evaluated the number of spot urine samples required and their screening performance for identifying individuals whose vegetable intake or total fruit and vegetable intake was below the study population mean. Screening performance was assessed by receiver operating characteristic analysis and the area under the curve (AUC). Results: For vegetable intake, the AUCs were >0.70 when either a single spot urine sample was collected at the second urine void after waking or ≥2 spot urine samples were collected at arbitrary time points. For total fruit and vegetable intake, AUCs were >0.70 when using a single spot urine sample collected at the second void after waking up. Conclusions: These findings suggest that a time-specific single spot urine sample (i.e., the second urine void after waking) or ≥2 spot urine samples collected at arbitrary time points may help in screening individuals with habitually insufficient vegetable intake.

BACKGROUND:Although numerous studies have separately examined fish and shellfish intakes, fish types, and n-3 PUFAs in relation to mortality, few studies have concurrently evaluated these factors, and findings in Asia, including in the Japanese population with high fish consumption, remain inconsistent. OBJECTIVES:The aim of this study was to investigate the associations of unsalted fish and shellfish, n-3 PUFA-rich fish, and marine-derived n-3 PUFA consumption with all-cause and cause-specific mortality in a Japanese population. METHODS:We analyzed 90,944 individuals (42,150 males and 48,794 females) from the Japan Public Health Center-based Prospective Study who completed a validated food frequency questionnaire between 1995 and 1998. Energy-adjusted intakes were categorized into quintiles. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for all-cause and cause-specific mortality using Cox proportional hazards regression models adjusted for potential confounders. RESULTS:After adjusting for covariates, a nonlinear association was observed between fish and shellfish intake and all-cause mortality in females, with the lowest mortality observed in Q4 [HR = 0.92(95% CI: 0.86, 0.98), P for nonlinearity = 0.022]. In males, higher intake of unsalted fish and shellfish was associated with a lower risk of cerebrovascular disease mortality in all quintiles except Q3 [Q2: HR = 0.78 (95% CI: 0.66, 0.92); Q4: HR = 0.77 (95% CI: 0.65, 0.91); Q5: HR = 0.84 (95% CI: 0.71, 0.99), P for nonlinearity = 0.017]. For n-3 PUFA-rich fish consumption, females had lower risks of all-cause (P for linear trend = 0.012) and cerebrovascular disease (P for linear trend = 0.005) mortality. CONCLUSIONS:A moderate fish and shellfish intake is associated with lower all-cause mortality in females. Higher n-3 PUFA-rich fish intake is also associated with lower cerebrovascular disease mortality in females. Among males, higher unsalted fish and shellfish intake is associated with lower cerebrovascular disease mortality. These findings suggest that different types of may be differentially associated with mortality outcomes.

AIM:We evaluated the association between the dietary fiber intake and the risk of dementia. METHODS:We performed a prospective study within the Japan Public Health Center-based Prospective Study involving 41,467 Japanese individuals aged 45-74 years between 1995-1998. Information regarding food intake was collected using a food frequency questionnaire. Disabling dementia was detected using the National Long-term Insurance System between 2006 and 2016. We calculated the hazard ratios and 95% confidence intervals for disabling dementia according to quartiles of soluble, insoluble, and total fiber intake and dietary fiber intake from food groups (cereals, potatoes and starches, soybeans, vegetables, and fruits) intake by sex. RESULTS:During an average follow-up period of 9.4, 4910 cases of disabling dementia were documented. The total fiber intake was inversely associated with the risk of disabling dementia in both men and women. The multivariable hazard ratios (95% confidence intervals: CIs) of disabling dementia for the highest versus lowest quartiles of total fiber intake were 0.82 (0.73-0.91) in women (p for trend ＜0.001) and 0.86 (0.74-1.00) in men (p for trend = 0.03). Similar inverse associations between soluble and insoluble fiber intake and the risk of disabling dementia were observed. The dietary fiber intake from cereals, potatoes, starches, vegetables, and fruits, but not soybeans, was inversely associated with the risk of disabling dementia, with some variation by sex. CONCLUSIONS:The dietary intake of total, soluble, and insoluble fiber was associated with a lower risk of disabling dementia. The associations did not vary materially according to the food source of the fiber.

A balanced diet has been associated with a lower risk of total and cardiovascular mortality. One intermediate function linking a balanced diet and lower mortality may be optimal insulin secretion. We examined the association between adherence to the Japanese Food Guide Spinning Top (JFGST) and serum C-peptide concentration, an indicator of basal insulin secretion, in a cross-sectional study in a Japanese population, in whom rice (refined grains) is the staple food. A blood sample was collected in November 2012 and a 12-d weighed food record was collected over the subsequent year. A total of 210 healthy residents aged 35-80 y (83 men, 127 women) were included in the analysis. Multiple regression analysis was performed with log-transformed serum C-peptide concentration as dependent variable and total JFGST score or each score by category of dish as independent variable, with adjustment for age and BMI. In both men and women, total JFGST score was inversely associated with serum C-peptide concentration. Slope in the percentage of differences for every 1-point score addition based the regression coefficients was -2.3% (p<0.001) in men and -1.6% (p<0.001) in women. For specified categories of dishes, scores for grain dishes, snacks and alcoholic beverages, and total energy were inversely associated with serum C-peptide concentrations among men. Among women, in contrast, scores for milk and for fruit were inversely associated with serum C-peptide concentrations. A balanced diet consistent with the JFGST was inversely associated with serum C-peptide concentration among middle-aged Japanese.

Background/Objectives: Unhealthy lifestyles lead to chronic low-grade inflammation, increasing the risk of colorectal cancer. Few studies in East Asia have examined the association between the dietary inflammation potential and colorectal cancer incidence. Therefore, we aimed to investigate this association further in the Japanese population. Methods: This study included 38,807 men aged 45-74 years who participated in the Japan Public Health Center-based prospective study (JPHC Study). The energy-adjusted dietary inflammatory index (E-DII) was derived from a food frequency questionnaire. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression models. Differences in risk due to a combination of E-DII and lifestyle were examined using interaction term. Results: During 14 years of follow-up, 1415 colorectal cancer cases occurred. A tendency to increased colorectal cancer risk was observed with consumption of pro-inflammatory diets among Japanese men (adjusted HR [95% CI] for the highest quintile: 1.20 [0.99-1.46], p trend = 0.08), with a significantly increased risk of colon cancer (HR: 1.28 [1.01-1.63], p trend = 0.03). A possible interaction was observed with alcohol consumption (p = 0.07), which was statistically significant for proximal colon cancer (HR: 1.14 [1.05-1.25] in drinkers; p interaction = 0.01). No significant interactions with other lifestyle factors were found. Conclusions: Consumption of pro-inflammatory diets increases colorectal cancer risk among Japanese men; alcohol consumption further increases this risk for drinkers. These findings suggest that colorectal cancer may be prevented through dietary modification.

BACKGROUND:Previous research has found that the Japanese dietary pattern is associated with lower mortality risk. However, the Japanese diet has been changing, such as increased intake of coffee and dairy products and reduced salt intake, which may affect the long lifespan of Japanese people. OBJECTIVES:We investigated the association between adherence to the new low salty food Japanese diet, with the addition of components of dairy products, coffee and salty foods, and all-cause and cause-specific mortality. METHODS:We included 93,049 participants aged 45-74 y without serious disease who were enrolled in a population-based prospective study. The score for adherence to a traditional Japanese Diet Index score (T-JDIs), consisting of 13 components (high intake of rice, miso soup, seaweeds, pickles, vegetables, non-salty seafood, salty seafood, green tea, fruits, soy products, mushrooms, salt by seasoning, and low intake of beef and pork) was assessed using energy-adjusted median intakes. We created low salty food JDIs (LS-JDIs) with lower salty food intake. In addition, scores of coffee and dairy products were added as new JDIs and new LS-JDIs (NLS-JDIs, 15-component). With the four JDIs, hazard ratios and 95% confidence intervals for all-cause and cause-specific mortality were estimated using a Cox proportional hazards model. RESULTS:During a median follow-up of 18.9 y, we documented 23,338 deaths. An inverse association was found between higher adherence to four JDIs and all-cause and cardiovascular disease (CVD) mortality in both genders. Especially for men, the point estimate with the highest adherence to NLS-JDIs was lower for all-cause and CVD mortality than that of T-JDIs. CONCLUSIONS:High adherence to all JDIs was associated with lower all-cause mortality in both genders. Especially, high adherence to NLS-JDIs was decreased with all-cause and CVD mortality risk more than that of T-JDIs in men.

Background and Objectives: Repeating food frequency questionnaires (FFQs) within the same population was reported to improve the validity of correlation coefficient (CC). However, the enhancement of validity in ranking agreement remains underreported. Herein, we assessed the validity of energy and nutrient intake estimates using single and multiple FFQs and their ability to rank individuals. Methods and Study Design: 213 men and women aged >= 20 years were recruited from the residents participating in the Tohoku Medical Megabank Project (TMM) cohort studies; three FFQs were conducted in November each year from 2019 to 2021, with 12-day weighted food records (WFRs) as the reference method. Spearman's rank CCs were calculated between single or multiple FFQs estimates and those obtained through the 12-day WFR. Additionally, the ranking agreement was compared based on cross-classification. Results: CCs between intake estimated using a single FFQ and 12-day WFR were moderate for several nutrients, with median CCs of 0.52 for men and 0.48 for women. CCs for multiple FFQs were slightly higher than that of single FFQ, with median CCs of 0.59 for men and 0.56 for women. Regardless of the number of FFQs, the proportion of subjects classified into the opposite extreme category was <= 5% for most nutrients. Conclusions: A single FFQ used for adults in the TMM cohort studies showed moderate validity. Estimates from multiple FFQs improved the accuracy slightly; nevertheless, this indicates that relying on a single FFQ is unlikely to result in a serious misclassification compared to using intake data from multiple FFQs over a relatively short period.

BACKGROUND:Polyphenols may play a protective role in carcinogenesis through a wide range of properties, including antioxidant and anti-inflammatory. However, evidence for the association between total dietary polyphenol intake and cancer risk in Asian populations is limited. OBJECTIVE:This population-based prospective study aimed to investigate the association between polyphenol intake and risk of overall and site-specific cancer among Japanese. METHODS:Participants were 41,907 men and 48,268 women aged 45-74 y with no previous cancer diagnosis in the Japan Public Health Center-based Prospective Study. Dietary polyphenol intake was estimated by a 147-item food frequency questionnaire administered in 1995-1998. Participants were divided into quintiles (Q) according to intakes of total polyphenol and polyphenol from foods, not including high-polyphenolic beverages (tea, coffee, and alcoholic beverages). Hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer risk were estimated using Cox proportional hazard regression models adjusted for potential confounders. RESULTS:During a median of 15.8 y of follow-up, 12,970 incident cancer cases (7999 men and 4971 women) were identified. We did not observe associations of lower risk of overall cancer with polyphenol intake. For site-specific cancers, compared with the lowest quintile (Q1), higher total polyphenol intake was associated with a lower risk of liver cancer in men (HRQ4: 0.67; 95% CI: 0.51, 0.89, HRQ5: 0.66; 95% CI: 0.48, 0.89; P-trend = 0.003) and women (HRQ5: 0.63; 95% CI: 0.39, 1.02; P-trend = 0.003), whereas higher polyphenol intake from foods not including tea, coffee, and alcoholic beverages was associated with a lower risk of colon cancer in men (HRQ4: 0.73; 95% CI: 0.58, 0.92, HRQ5: 0.72; 95% CI: 0.54, 0.96; P-trend = 0.07). CONCLUSIONS:The results of the present study do not support a substantial role for dietary polyphenols in overall cancer prevention. Total polyphenol may reduce the risk of liver cancer, and polyphenol from foods, not including tea, coffee, and alcoholic beverages, may reduce the risk of colon cancer.

Baseline characteristics of participants without blood sample

BACKGROUND:The Ministry of Health, Labour, and Welfare in Japan has published a meal-based dietary guideline (Healthy Meal); however, its relationship with health outcomes remains unclear. This observational study examined the association between adherence to Healthy Meal and all-cause and cause-specific mortalities. METHODS:We analyzed data from the Japan Public Health Center-based Prospective Study (JPHC Study) with a mean follow-up of 19.0 years, including 40,222 men and 47,350 women aged 45-75 years with no history of cancer, stroke, ischemic heart disease, chronic liver disease, or kidney disease. Adherence to Healthy Meal was scored using dietary intake from a validated food frequency questionnaire. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cause-specific mortalities across score quartiles. RESULTS:A higher Healthy Meal adherence score was significantly associated with a lower risk of all-cause mortality. The multivariable-adjusted HRs for the highest versus the lowest adherence group were 0.86 (95% CI, 0.82-0.91, P < 0.001 for trend) in men and 0.92 (95% CI, 0.87-0.98, P = 0.005 for trend) in women. Significant associations with a lower risk of cerebrovascular disease and respiratory disease mortalities were observed in both sexes. In contrast, significant associations were observed for cancer, cardiovascular disease, and heart disease mortalities in men only. CONCLUSION:Higher adherence to the Japanese meal-based dietary guideline was associated with a lower risk of all-cause, cerebrovascular disease, and respiratory disease mortalities in Japanese men and women, and cancer, cardiovascular disease, and heart disease mortalities in men only.

Background: The Tohoku Medical Megabank Project has initiated the Birth and Three-Generation Cohort Study (TMM BirThree Cohort Study) including genomic and omics investigations and conducted a self-administered food frequency questionnaire with the response option “constitutionally unable to eat or drink it” for individual food items (TMM-FFQ) for pregnant women. This study evaluated the validity of the TMM-FFQ among pregnant women. Methods: Participants comprised 122 pregnant women aged ≥20 years residing in Miyagi Prefecture who completed weighed food records (WFRs) for 3 days as reference intake and the TMM-FFQ during mid-pregnancy. Correlations between nutrient or food group intakes based on the WFR and the TMM-FFQ were calculated using Spearman’s rank correlation coefficients (CCs), adjusting for energy intake and correcting for random within-individual variation of WFR. Cross-classification was also conducted according to quintiles using the WFR and TMM-FFQ data. Results: The percentages of participants who chose the “constitutionally unable to eat or drink it” option were >3% for seven food and drink items. CCs were >0.30 for 31 nutrients; the median across energy and 44 nutrients was 0.41. CCs were >0.30 for 14 food groups; the median across 20 food groups was 0.35. The median percentages of cross-classification into exact plus adjacent quintiles and extreme quintiles were 63.1% and 3.3% for energy and nutrients and 61.9% and 4.1% for food groups, respectively. Conclusion: The validity of the TMM-FFQ compared with the WFR was reasonable for certain nutrients and food groups among pregnant women in the TMM BirThree Cohort Study.

BACKGROUND:More research is needed to clarify the health effects of dietary carotenoid intakes, and this requires the use of high-quality assessments of habitual dietary intake. Cohort studies from the Tohoku Medical Megabank Organization included a self-administered food frequency questionnaire (TMM-FFQ) for community-dwelling adults. This study evaluated the validity of carotenoid intakes derived from the TMM-FFQ using serum carotenoid concentrations as the gold standard. METHODS:In Miyagi Prefecture, 88 men and 124 women aged ≥20 years voluntarily agreed to participate in the study and provided completed TMM-FFQs and blood samples in 2019 and 2021. Carotenoids examined included α-carotene, β-carotene, β-cryptoxanthin, and lycopene. Intraclass correlation coefficients (ICCs) were calculated to assess correlations between serum concentrations in 2019 and 2021. Spearman's rank correlation coefficients were calculated to evaluate the correlations between energy-adjusted dietary carotenoid intakes from the TMM-FFQ in 2021 and the average serum carotenoid concentrations in 2019 and 2021, with correction for the attenuating effect of random within-individual variation. RESULTS:The ICCs between serum concentrations over the 2 years were >0.50 for all carotenoids. Among men, correlation coefficients were 0.33 for α-carotene, 0.42 for β-carotene, 0.50 for β-cryptoxanthin, and -0.09 for lycopene. Among women, the coefficients were lower than those for men, except for lycopene: 0.11 for α-carotene, 0.23 for β-carotene, 0.21 for β-cryptoxanthin, and 0.28 for lycopene. CONCLUSION:The TMM-FFQ demonstrated reasonable validity for assessing intakes of α-carotene, β-carotene, and β-cryptoxanthin among men, but not among women, in the TMM cohort studies when using serum concentrations as the gold standard.

BACKGROUND & AIMS:Salt reduction remains an important issue in population-level studies of diet. One unresolved issue is whether adherence to a food guide which does not assess dietary salt can lead to a reduction in salt intake. METHODS:This study aimed to investigate the association between adherence to a food guide calculated by weighed food records (WFRs) or a Food Frequency Questionnaire (FFQ), and urinary sodium and potassium excretion and sodium-to-potassium ratio. Further, salt-added scores were developed and analyzed. We used cross-sectional data, including data from 12-day WFRs, five 24-h urine collections, and an FFQ. A total of 248 participants aged 35-80 years were surveyed between 2012 and 2013. Main outcomes were 24-h urinary sodium and potassium excretion and sodium-to-potassium excretion ratio. Multiple regression analysis was performed with urinary excretion as the dependent variable and the food guide score calculated by WFRs and the FFQ as independent variables. Because scores are not proportional to intake under this food guide scoring method, Spearman's correlation coefficients were calculated between the score and urinary excretion, and between the number of servings and urinary excretion. RESULTS:When scored by WFRs, the higher food guide score group tended to have lower sodium excretion (-129 mg/day per one quartile increase; P for trend, 0.051), higher potassium excretion (137 mg/day per one quartile increase, P < 0.01), and lower sodium-to-potassium ratio (-0.32 per one quartile increase, P < 0.01). When accompanied by salt-added scores, total score was associated with further reductions in sodium excretion (-218 mg/day per one quartile increase; P for trend, <0.001). CONCLUSIONS:Even with a study food guide which does not assess dietary salt, high adherence to the guide tended to be associated with lower sodium excretion and sodium-to-potassium ratio and higher potassium excretion. This inverse association with sodium excretion was strengthened by the addition of a salt-added score.

BACKGROUND:One of the factors for not achieving a reduced salt diet may be the difficulties in screening individuals according to their quantitative salt consumption. Accordingly, we examined the performance of a simplified 13-item salt check sheet as a quantitative tool for screening excessive salt intake by comparing with the salt intake amount measured by 24-hour urinary sodium (salt equivalent g/day) excretion. METHODS:One hundred fifty-four participants (57 males and 97 females) from Kanagawa, Tokyo, and Nara Prefectures in Japan were included. In this study, which the design is a cross-sectional validation study, the salt intake amount was used as a diagnostic criterion, and corresponding receiver operating characteristic (ROC) curves were prepared based on the sensitivity and specificity of each score of the salt check sheet. RESULTS:The average salt intake were 13.5 and 10.2 g/day for males and females, respectively. When using the total score, among males, the area under the ROC curve (AUC) was moderate (0.702; 95% confidence interval [CI], 0.543-0.862), confirming its value as a diagnostic tool for salt intake of ≥10 g/day. In females, the AUCs were low for any criteria. When score calculation item was limited to three that contributed to the higher salt intake in this population, the AUC for ≥10 g salt/day was moderate (0.700; 95% CI, 0.595-0.805). CONCLUSION:The salt check sheet was found to be useful in screening for excessive salt intake only in males. For females, it was suggested that it could be used only when three specific items are used.

ORs and 95% CIs of breast cancer according to the biomarkers of acrylamide exposure (stratified analysis)

Background: The Tohoku Medical Megabank Project (TMM) was established to realize personalized healthcare and medicine using genomic and omics data. This study evaluated the validity and reproducibility of food group intakes derived from a self-administered food frequency questionnaire (TMM-FFQ) that included the response option “constitutionally unable to eat/drink it” among community-dwelling Japanese adults. Methods: Participants comprised 89 men and 124 women aged ≥20 years from Miyagi Prefecture. Participants completed weighed food records (WFRs) for 3 consecutive days per season as reference intake and FFQs in 2019 (FFQ1) and 2021 (FFQ3). Spearman’s rank correlation coefficients (CCs) were calculated for correlations between food group intakes estimated from the 12-day WFR and FFQ3 (validity), and for correlations between those estimated from the FFQ1 and FFQ3 (reproducibility). Cross-classification according to quintiles using FFQ and WFR data was also performed. Results: The percentage of participants who chose the “constitutionally unable to eat/drink it” option was non-negligible for some food groups. In the validity analysis, CCs were >0.40 for many food groups; the median across 21 food groups was 0.49 in men and 0.45 in women. The median percentages of cross-classification into exact plus adjacent quintiles were 73.0% in men and 66.9% in women. In the reproducibility analysis, CCs were >0.50 for many food groups; the median across 21 food groups was 0.60 in men and 0.51 in women. Conclusion: The validity of the TMM-FFQ compared with 12-day WFR and the reproducibility of the TMM-FFQ were reasonable for food groups in the TMM cohort studies.

Accurate measurement of sodium intake in the diet is challenging, and epidemiological studies can be hampered by the attenuation of associations due to measurement error in sodium intake. A prediction formula for habitual 24-h urine sodium excretion and sodium-to-potassium ratio might lead to more reliable conclusions. Five 24-h urinary samples and two Food Frequency Questionnaires (FFQs) were conducted among 244 Japanese participants aged 35–80 years. We conducted multivariate linear regression analysis with urinary excretion as dependent variables and eating behaviour and food frequency as independent variables. Empirical weights of sodium excretion and sodium-to-potassium ratio were extracted. Preliminary validity was also assessed by randomly dividing the subjects into development and validation groups based on the correlation coefficient between estimates by the prediction formula and urinary excretion. Taste preference, soy sauce use at the table, frequency of pickled vegetables intake and number of bowls of miso soup were extracted as determinants of sodium excretion. Correlation coefficients between the estimates and urinary excretion for men and women were 0.42 and 0.43, respectively, for sodium and 0.49 and 0.50, respectively, for sodium-to-potassium ratio. This prediction formula may provide more accurate estimation of sodium intake and sodium-to-potassium ratio than the food composition approach.

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, β-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, β-carotene, vitamin C, and vitamin E, and prostate cancer risk. Although higher lycopene intake was associated with increased risk of prostate cancer (highest vs lowest quintile, HR 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). Conclusion: Our study suggested no association between antioxidant intake of vitamins and prostate cancer risk.

Recently, web-based dietary assessment tools for the targeted population have been developed and used to estimate the dietary intake level in several epidemiological studies. This study aimed to examine the validity of estimating energy and nutrient intake by the web-based 24 h dietary recall (Web24HR), which we developed for the Japanese population. Overall, 228 adults aged ≥20 years who agreed to participate were included. Web24HR was administered three times per person: twice within 3 weeks and once 3 months later. The data on 3-day weighed food records (WFR) at 3-month intervals in the four seasons were collected using the reference method. The intake of energy and nutrients between Web24HR and WFR were compared using Pearson’s correlation coefficients and the Bland–Altman analysis. As results, the correlations were moderate for both men (median r = 0.51) and women (median r = 0.38) except for iodine, retinol, retinol equivalents, and β-tocopherol. The Bland–Altman method revealed that the bias in intake was within ±10% for most nutrients, except for cholesterol, iodine, vitamin C, and the water content, in both sexes. Additionally, monounsaturated fatty acids in men and β-cryptoxanthin in women exhibited an underestimation of more than 10%. In conclusion, the Web24HR intake assessment showed moderate correlations for most nutrients in both sexes. The bias in intake was within ±10% for most nutrients, but there were discrepancies for some nutrients. This tool’s performance is comparable to Japan’s standard dietary exposure assessment methods and will be helpful for future applications in epidemiological studies, though caution is needed for certain nutrient assessments.