Reproducibility and validity of dietary patterns assessed by a food frequency questionnaire used in the 5-year follow-up survey of the Japan Public Health Center-Based Prospective Study

Food group intakes and high-sensitivity C-reactive protein among community-dwelling Japanese adults: a cross-sectional study

OBJECTIVE

Healthy dietary patterns have been linked to lower levels of chronic inflammation. The present study aimed to investigate the associations between food group intakes and high-sensitivity C-reactive protein (hsCRP) among community-dwelling adults.

DESIGN

Cross-sectional.

SETTING

Three areas in Japan (Shiga, Fukuoka, or Kyushu and Okinawa).

PARTICIPANTS

The present analysis included 13 648 participants (5126 males and 8522 females; age range, 35-69 years) who had been enrolled in the baseline survey of the Japan Multi-Institutional Collaborative Cohort Study. Food group intakes were estimated using a FFQ. Multiple linear regression was used to examine associations between the quartiles of each energy-adjusted food group intake and log-transformed hsCRP.

RESULTS

The following concentration ratios of hsCRP after comparing the highest and lowest quartiles of food group intake were significant: in males, 1·12 (95 % CI 1·02, 1·22) for processed meat, 1·13 (95 % CI 1·03, 1·24) for fish and 0·83 (95 % CI 0·76, 0·90) for nuts; in females, 0·89 (95 % CI 0·81, 0·97) for bread, 1·11 (95 % CI 1·03, 1·19) for processed meat, 0·86 (95 % CI 0·80, 0·92) for vegetables, 1·19 (95 % CI 1·11, 1·29) for fruit, 0·90 (95 % CI 0·84, 0·97) for nuts and 0·88 (95 % CI 0·82, 0·95) for green tea.

CONCLUSIONS

Processed meat and nut intakes were associated with higher and lower hsCRP levels, respectively, in both sexes. However, for several food groups, including fish and fruit, previous findings from dietary pattern analyses were not supported by the present analyses at the food group level.

Mushroom intake and risk of incident disabling dementia: the Circulatory Risk in Communities Study (CIRCS)

It is uncertain whether dietary intake of mushrooms rich in dietary fibre and several antioxidants is associated with a lower risk of dementia. We sought to examine prospectively the association between mushroom intake and the risk of disabling dementia. We performed a prospective study involving 3750 people aged 40 to 64 years residing in three communities who participated in an annual cardiovascular risk survey from 1985 to 1999. Cases of incident disabling dementia were surveyed from 1999 to 2020. We calculated the hazard ratios (HR) and 95 % CI for incident total dementia according to mushroom intake among participants with or without a history of stroke. During a mean 16·0 years' follow-up in 3739 eligible participants, 670 people developed disabling dementia. For women, mushroom intake was inversely associated with the risk of total dementia and the association was confined to dementia without a history of stroke. The multivariable HR (95 % CI) for total dementia in women were 0·81 (0·62, 1·06) for mushroom intake of 0·1-14·9 g/d and 0·56 (0·42, 0·75) for mushroom intake above 15·0 g/d (Pfor trend = 0·003) compared with no intake. The corresponding HR (95 % CI) for dementia without a history of stroke were 0·66 (0·47, 0·93) and 0·55 (0·38, 0·79) (Pfor trend = 0·01). In men, no associations were observed between mushroom intake and the risk of disabling dementia. Among Japanese women, dietary mushroom intake was associated with a lower risk of disabling dementia.

Validity and reproducibility of the PERSIAN Cohort food frequency questionnaire: assessment of major dietary patterns

BACKGROUND

Dietary patterns, encompassing an overall view of individuals' dietary intake, are suggested as a suitable means of assessing nutrition's role in chronic disease development. The aim of this study was to evaluate the validity and reproducibility of a food frequency questionnaire (FFQ) designed for use in the Prospective Epidemiological Research Studies in IrAN (PERSIAN), by comparing major dietary patterns assessed by the FFQ with a reference method.

METHODS

Study participants included men and women who enrolled in the PERSIAN Cohort Study at seven of the eighteen centers. These centers were chosen to include dietary variations observed among the different Iranian ethnic populations. Two FFQ were completed for each participant over a one-year study period (FFQ1 upon enrollment and FFQ2 at the end of the study), with 24 interviewer-administered 24-hour dietary recalls (24 h) being completed monthly in between. Spearman correlation coefficients (SCC) were used comparing FFQs 1 and 2 to the 24 h to assess validity, while FFQ1 was compared to FFQ2 to assess reproducibility of the questionnaire.

RESULTS

Three major dietary patterns-Healthy, Low Protein/High Carb and Unhealthy-were identified, accounting for 70% of variance in the study population. Corrected SCC ranged from 0.31 to 0.61 in the validity and from 0.34 to 0.57 in reproducibility analyses, with the first two patterns, which accounted for over 50% of population variance, correlated at above 0.5 in both parameters, showing acceptable findings.

CONCLUSIONS

The PERSIAN Cohort FFQ is suitable for identification of major dietary patterns in the populations it is used for, in order to assess diet-disease relationships.

Dietary Patterns and Health: Insights From NESR Systematic Reviews to Inform the Dietary Guidelines for Americans

This perspective article shares unique insights from the extensive experience of the US Department of Agriculture Nutrition Evidence Systematic Review branch in conducting systematic reviews on dietary patterns and health outcomes to inform the Dietary Guidelines for Americans. Methodological approaches for reviewing dietary patterns research are described, including approaches to operationalizing definitions and analyzing labeled dietary patterns. The review also describes techniques for synthesizing dietary patterns research across life stages in systematic reviews that inform food-based, federal dietary guidance. Current research activities and recommendations for how to improve or address gaps in dietary patterns research in the future are also discussed.

Socio-demographic characteristics and dietary pattern of community-dwelling adults in Abia State, Nigeria

Objective

Identification of dietary patterns and their association with socio-demographic factors.

Design

Community-based cross-sectional study design.

Setting

Urban and rural communities in Abia State, Nigeria.

Participants

Eight hundred and sixty-eight (868) male and female adults aged 20 to 59 years.

Methods

Identification of Dietary patterns (DP) by Principal Component Analysis (PCA) based on the consumption of 10 food groups, assessed using a 7-day qualitative food frequency questionnaire. Bivariate and multivariate logistic regression analyses evaluated the association between identified patterns and socio-economic factors.

Results

Two dietary patterns 'traditional and convenience DPs were identified, explaining 52% of the total variance. The traditional DP was loaded with starchy staples, vegetable soups/sauces, and animal proteins. The convenience DP was characterised by high factor loading of processed cereals, carbonated drinks and alcoholic beverages. Larger households (>3) had lower odds of adhering to high traditional DP [AOR =0.633; 95% CI (0.429-0.934); p = 0.021]. Females [AOR =1.586; 95% CI (1.104-2.279); p = 0.013] and middle-aged adults (AOR = 1.750; 95% CI (1.075-2.848);p = 0.024] were more likely to adhere to the convenience DP, whereas, the odds of adhering to the convenience pattern was lower among adults residing in rural areas [AOR =0.3161.586; 95% CI (0.219-0.456); p = 0.001].

Conclusion

Socio-economic variables (age, gender, household size and place of residence) were associated with dietary patterns among community dwellers in Nigeria.

Funding

None declared.

Associations between sugar-sweetened beverages before and during pregnancy and offspring overweight/obesity in Japanese women: the TMM BirThree Cohort Study

OBJECTIVE

The association between high sugar-sweetened beverages (SSB) intake during pregnancy and offspring overweight/obesity has been reported only from Western countries. The objective of this study was to examine the association between SSB intake before and during pregnancy and offspring overweight/obesity among Japanese women.

DESIGN

Japanese prospective birth cohort study.

SETTING

We analysed mother-offspring pairs who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study from 2013 to 2017. SSB intake during pregnancy was evaluated using the FFQ and classified into three groups: none (0 g/d), medium (<195 g/d) and high (>195 g/d). Overweight or obesity at 1 year of age in offspring was defined as having a BMI Z-score greater than 2 sd, calculated based on the BMI reference data for Japanese children. Multiple logistic regression analyses were performed to examine the associations between SSB intake before and during pregnancy and offspring overweight/obesity, after adjusting for covariates.

PARTICIPANTS

Japanese mother-offspring pairs (n 7114).

RESULTS

The overweight/obesity rate of the offspring was 8·8 %. Pregnant women with a high intake of SSB in early to mid-pregnancy had a higher risk of overweight/obesity in their offspring compared with those who did not; the OR was 1·52 (95 % CI (1·09, 2·12)).

CONCLUSIONS

High SSB intake in early to mid-pregnancy was associated with an increased risk of offspring overweight/obesity at 1 year of age.

Differences in the Association Between Alcoholic Beverage Type and Serum Urate Levels Using Standardized Ethanol Content

IMPORTANCE

Differences have been observed in the association of serum urate levels with consumption of different types of alcoholic beverages. However, previous studies have not standardized the unit of intake for ethanol content, and only limited types of alcoholic beverages have been evaluated.

OBJECTIVE

To examine differences in the association of serum urate levels with various types of alcoholic beverages when their intakes are standardized for ethanol content.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cross-sectional study was conducted using data from participants aged 20 years or older who completed a medical checkup at St Luke's International University in Japan between October 1, 2012, and October 31, 2021. Participant demographics, blood test results, and lifestyle questionnaire data were used as covariates. Analysis was performed in December 2021.

EXPOSURES

Consumption of alcoholic beverages, including beer, sake (rice wine), shochu (Japanese spirit), wine, and whiskey.

MAIN OUTCOMES AND MEASURES

Serum urate levels were measured during the medical checkup. The beverage unit was standardized to 1 standard drink, which contained 20 g of ethanol. Multivariable linear regression including interaction terms of alcohol consumption and dominant alcoholic beverage was performed.

RESULTS

This study included 78 153 participants. Their mean (SD) age was 47.6 (12.8) years; 36 463 (46.7%) were men and 41 690 were women (53.3%). A total of 45 755 participants (58.5%) were regular alcohol drinkers. Consistent associations of serum urate levels with alcohol consumption were observed in the beer-dominant group, with β coefficients (for 1 standard drink per day) of 0.14 mg/dL (95% CI, 0.11-0.17 mg/dL; P < .001) for men and 0.23 mg/dL (95% CI, 0.20-0.26 mg/dL; P < .001) for women. A moderate increase in serum urate levels was observed in the wine-dominant group compared with a modest and nonsignificant increase in the sake-dominant group, with β coefficients (for 1 standard drink per day) for the latter group of 0.05 mg/dL (95% CI, -0.01 to 0.10; P = .10) for men and 0.04 mg/dL (95% CI, -0.05 to 0.14 mg/dL; P = .38) for women. Restricted cubic splines showed different patterns in associations of serum urate levels with ethanol intake by dominant alcoholic beverages.

CONCLUSIONS AND RELEVANCE

The results of this study suggest that the extent of the association of serum urate levels with alcohol intake was different for alcoholic beverages even after ethanol content was standardized. Higher beer consumption among men and women was consistently associated with higher serum urate levels, whereas sake was not associated with changes in serum urate levels. Therefore, alcoholic beverage type, in addition to ethanol content, should be considered as a factor contributing to hyperuricemia.

Vegetable and fruit intake and colorectal cancer risk by smoking status in adults: The Japan Public Health Center-based Prospective Study

BACKGROUND

Cigarette smoke contains many oxidants and free radicals which may affect the association between vegetable and fruit intake and colorectal cancer (CRC) risk. However, this relationship remains unclear.

OBJECTIVE

This study aimed to investigate the associations between vegetable and fruit intake and CRC risk by smoking status.

METHODS

The Japan Public Health Center-based Prospective Study is a population-based prospective cohort study. Participants completed a self-administered questionnaire in 1995-1999 (baseline survey) and were followed through to 2013. At the baseline survey, 89,283 residents (41,797 men and 47,486 women) aged 45-74 years were included. Participants were asked about their lifestyle and dietary habits. To investigate the association of vegetable and fruit intake with risk of CRC, Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). We analyzed the relationship between vegetable and fruit intake and CRC risk stratified by sex and smoking status.

RESULTS

During follow-up, 2261 participants were diagnosed with CRC. Overall, vegetable and fruit intake were not associated with CRC risk in either sex. When stratified by sex and smoking status, CRC risk among male never smokers was inversely associated with intake of vegetables and fruit combined (HR: 0.72; 95% CI: 0.53, 0.98; highest vs lowest quartile p trend = 0.01) and fruit alone (HR: 0.62; 95% CI: 0.45, 0.86; p trend < 0.01).

CONCLUSIONS

Cigarette smoking may affect the association between vegetable and fruit intake and CRC risk among men.

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 (β =  - 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.

Dietary sodium sources according to four 3-d weighed food records and their association with multiple 24-h urinary excretions among middle-aged and elderly Japanese participants in rural areas

Reducing Na intake is an urgent global challenge, especially in East Asia and high-income Asia-Pacific regions. However, the sources of Na and their effects on urinary Na excretion have not been fully studied. We sought to clarify these sources and their association with urinary Na excretion. We examined four 3-d weighed food records and five 24-h urinary collections from each of 253 participants in Japan, aged 35-80 years, between 2012 and 2013. We compared the levels of Na according to four categories: foods contributing to discretionary or non-discretionary Na intake, the situation in which dishes were cooked and consumed, food groups and types of cuisine. We also conducted regression analysis in which 24-h urinary Na excretion was a dependent variable and the amounts of food intake in the four categories were independent variables. Levels of Na were the highest in discretionary intake (60·6 %) and in home-prepared dishes (84·0 %). Of the food groups, miso soup showed the highest percentage contribution to Na intake (13·3 %) after seasonings such as soya sauce. In the regression analysis, the standardised coefficient for foods of non-discretionary Na sources was larger than that for discretionary sources, whereas that for home-prepared dishes was consistent with the levels of Na in those foods. Pickled products, followed by fresh fish and shellfish, miso soup and rice, were associated with high urinary Na excretion. Thus, discretionary foods (such as miso soup) contribute the most to Na consumption, although non-discretionary intake (such as pickled vegetables) may influence urinary Na excretion.

The Reproducibility and Relative Validity of a Food Frequency Questionnaire for Identifying Iron-Related Dietary Patterns in Pregnant Women

Analyzing pregnant women’s iron intake using dietary patterns would provide information that considers dietary relationships with other nutrients and their sources. The objective of this study was to evaluate the reproducibility and relative validity of a Qualitative Food Frequency Questionnaire to identify iron-related dietary patterns (FeP-FFQ) among Mexican pregnant women. A convenience sample of pregnant women (n = 110) completed two FeP-FFQ (FeP-FFQ1 and FeP-FFQ2) and a 3-day diet record (3DDR). Foods appearing in the 3DDR were classified into the same food groupings as the FeP-FFQ, and most consumed foods were identified. Exploratory factor analysis was used to determine dietary patterns. Scores were compared (FeP-FFQ for reproducibility and FeP-FFQ1 vs. 3DDR for validity) through intraclass correlation coefficients (ICC), cross-classification, Bland−Altman analysis, and weighed Cohen kappa (κw), using dietary patterns scores tertiles. Two dietary patterns were identified: “healthy” and “processed foods and dairy”. ICCs (p < 0.01) for “healthy” pattern and “processed foods and dairy” pattern were 0.76 for and 0.71 for reproducibility, and 0.36 and 0.37 for validity, respectively. Cross-classification and Bland−Altman analysis showed good agreement for reproducibility and validity; κw values showed moderate agreement for reproducibility and low agreement for validity. In conclusion, the FeP-FFQ showed good indicators of reproducibility and validity to identify dietary patterns related to iron intake among pregnant women.

Japanese Diet and Mortality, Disability, and Dementia: Evidence from the Ohsaki Cohort Study

The Japanese dietary pattern has long been discussed as one of the factors behind the longevity of Japanese people. However, the health benefits of the Japanese dietary pattern have not been fully elucidated. We published the first report in the world regarding the relation between the Japanese dietary pattern and cardiovascular disease mortality in 2007 using cohort studies including Japanese residents of Ohsaki City, Miyagi Prefecture, Japan. Since then, we have developed the Japanese Diet Index (JDI) that was based on previous findings to assess the degree of the Japanese dietary pattern and to advance the evidence on the health effects of the Japanese dietary pattern. So far, we have explored the associations between the JDI score (in quartiles) and various outcomes. For all-cause mortality, in comparison to Q1 (the lowest), the multivariable hazard ratios (HRs) and 95% confidence intervals (95%CIs) were 0.92 (0.85–1.00) for Q2, 0.91 (0.83–0.99) for Q3, and 0.91 (0.83–0.99) for Q4 (the highest). For functional disability, the multivariable HRs (95%CIs) were 0.94 (0.81–1.09) for Q2, 0.90 (0.77–1.05) for Q3, and 0.79 (0.68–0.92) for Q4. For dementia, the multivariable HRs (95%CIs) were 0.88 (0.74–1.05) for Q2, 0.87 (0.73–1.04) for Q3, 0.79 (0.66–0.95) for Q4. In addition, people with higher adherence to the Japanese dietary pattern also showed decreases in disability and dementia risks. The purpose of this article was to review all six papers, summarize the health effects of the Japanese dietary pattern, and discuss implications for future research.

Dietary patterns in association with the expression of pro-metastatic genes in primary breast cancer

PURPOSE

Metastasis is a major leading cause of mortality in female breast cancer (BrCa). Cellular motility is a pathological process of metastasis remarked by the overexpression of cortactin (CTTN), Ras homolog family member-A (RhoA), and Rho-associated kinase (ROCK) genes. Their balance is responsible for upholding the integrity of healthy epithelial cell junctions. This study aimed to explore the associations between a posteriori dietary patterns and the expression levels of pro-metastatic genes in primary BrCa.

METHODS

In this consecutive case series, 215 eligible women, newly diagnosed with histologically confirmed non-metastatic BrCa (stage I-IIIA), were recruited from Hospitals in Tabriz, Northwestern Iran (2015-2017). The tumoral expression levels of genes were quantified using real-time reverse transcription-polymerase chain reaction. Dietary data assessment was carried out using a validated food frequency questionnaire.

RESULTS

Three dietary patterns were identified using principal component analysis (KMO = 0.699). Adherence to the "vegan" pattern (vegetables, fruits, legumes, nuts, seeds, and whole grains) was inversely associated with the expression levels of RhoA (OR_Adj.T3vs.T1 = 0.24, 95%CI 0.07-0.79) and ROCK (OR_Adj.T3vs.T1 = 0.26, 95%CI 0.08-0.87). In addition, the highest adherence to the "prudent" pattern (spices, seafood, dairy, and vegetable oils) decreased the odds of overexpressions at RhoA (OR_Adj.T3vs.T1 = 0.26, 95%CI 0.08-0.84) and ROCK genes (OR_Adj.T3vs.T1 = 0.29, 95%CI 0.09-0.95). The highest adherence to "Western" pattern (meat, processed meat, hydrogenated fat, fast food, refined cereals, sweets, and soft drinks) was a risk factor associated with the overexpression of RhoA (OR_Adj.T3vs.T1 = 3.15, 95%CI 1.12-8.85).

CONCLUSION

Adherence to healthy dietary patterns was significantly associated with the downregulation of pro-metastatic genes. Findings provided new implications to advance the nutrigenomic knowledge to prevent the odds of over-regulations in pro-metastatic genes of the primary BrCa.

Cross-sectional associations between the types/amounts of beverages consumed and the glycemia status: The Japan public health center-based Prospective Diabetes study

Background

The associations between the types/amounts of beverages consumed in daily life and measures of the glycemia status were investigated in a Japanese population-based cohort.

Methods

Data from the baseline survey of the Japan Public Health Center-based Prospective Diabetes cohort were used. A cross-sectional analysis was performed in 3852 men and 6003 women who were evaluated under the fasting condition. The daily consumptions of coffee, green tea, oolong tea, black tea, soft drinks, fruit juices, or plain water were assessed using a self-reported questionnaire. Multivariable-adjusted linear regression analyses were performed using measures of the glycemia status (fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) ) as dependent variables and the types/amounts of beverages consumed as the independent variables, to calculate the differences according to the types/amounts of beverages consumed.

Results

In the multivariable-adjusted models, coffee consumption of ≥240 mL/day was significantly associated with a change of the FPG level by −1.9 mg/dL in men (p = 0.013) and −1.4 mg/dL in women (p = 0.015), as compared to coffee consumption of 0 mL/day. No significant association of the FPG level was observed with any of the other types/amounts of beverages consumed. On the other hand, significant associations were found between the HbA1c levels and consumption of several types of beverages.

Conclusions

High coffee consumption was associated with lower FPG levels in this Japanese population. Some unexpected associations of the HbA1c levels with the consumption of some types of beverages were observed, which need to be further investigated.

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.

A review of harmonization methods for studying dietary patterns

Data harmonization is the process by which each of the variables from different research studies are standardized to similar units resulting in comparable datasets. These data may be integrated for more powerful and accurate examination and prediction of outcomes for use in the intelligent and smart electronic health software programs and systems. Prospective harmonization is performed when researchers create guidelines for gathering and managing the data before data collection begins. In contrast, retrospective harmonization is performed by pooling previously collected data from various studies using expert domain knowledge to identify and translate variables. In nutritional epidemiology, dietary data harmonization is often necessary to construct the nutrient and food databases necessary to answer complex research questions and develop effective public health policy. In this paper, we review methods for effective data harmonization, including developing a harmonization plan, which common standards already exist for harmonization, and defining variables needed to harmonize datasets. Currently, several large-scale studies maintain harmonized nutrient databases, especially in Europe, and steps have been proposed to inform the retrospective harmonization process. As an example, data harmonization methods are applied to several U.S longitudinal diet datasets. Based on our review, considerations for future dietary data harmonization include user agreements for sharing private data among participating studies, defining variables and data dictionaries that accurately map variables among studies, and the use of secure data storage servers to maintain privacy. These considerations establish necessary components of harmonized data for smart health applications which can promote healthier eating and provide greater insights into the effect of dietary patterns on health.

Consumption of flavonoid-rich fruits, flavonoids from fruits and stroke risk: a prospective cohort study

We sought to examine the prospective associations of specific fruit consumption, in particular flavonoid-rich fruit (FRF) consumption, with the risk of stroke and subtypes of stroke in a Japanese population. A study followed a total of 39 843 men and 47 334 women aged 44-76 years, and free of CVD, diabetes and cancer at baseline since 1995 and 1998 to the end of 2009 and 2012, respectively. Data on total and specific FRF consumption for each participant were obtained using a self-administrated FFQ. The hazard ratios (HR) of stroke in relation to total and specific FRF consumption were estimated through Cox proportional hazards regression models. During a median follow-up of 13·1 years, 4091 incident stroke cases (2557 cerebral infarctions and 1516 haemorrhagic strokes) were documented. After adjustment for age, BMI, study area, lifestyles, dietary factors and other risk factors, it was found that total FRF consumption was associated with a significantly lower risk of stroke in women (HR = 0·70; 95 % CI 0·58, 0·84), while the association in men was not significant (HR = 0·93; 95 % CI 0·79, 1·09). As for specific FRF, consumptions of citrus fruits, strawberries and grapes were found associated with a lower stroke risk in women. Higher consumptions of FRF, in particular citrus fruits, strawberries and grapes, were associated with a lower risk of developing stroke in Japanese women.

Seaweed Intake and Risk of Cardiovascular Disease: The Circulatory Risk in Communities Study (CIRCS)

AIM

Seaweed contains soluble dietary fibers, potassium, and flavonoids and was recently reported to be inversely associated with the risk of coronary heart disease and mortality from stroke. However, epidemiological evidence on this issue has remained scarce.

METHODS

At the baseline survey of four Japanese communities between 1984 and 2000, we enrolled 6,169 men and women aged 40-79 years who had no history of cardiovascular disease. We assessed their seaweed intake using the data from a 24 h dietary recall survey and categorized the intake into four groups (0, 1-5.5, 5.5-15, and ≥ 15 g/day). We used sex-specific Cox proportional hazards models to examine the association between seaweed intake and risk of cardiovascular disease (stroke, stroke subtypes, and coronary heart disease).

RESULTS

During the 130,248 person-year follow-up, 523 cases of cardiovascular disease occurred: 369 cases of stroke and 154 cases of coronary heart disease. Seaweed intake levels were inversely associated with the risk of total stroke and cerebral infarction among men but not among women. Adjustment for cardiovascular risk factors did not change the associations: the hazard ratios (95% confidence intervals; P for trend) for the highest versus lowest categories of seaweed intake were 0.63 (0.42-0.94; 0.01) for total stroke and 0.59 (0.36-0.97; 0.03) for cerebral infarction. No associations were observed between seaweed intake and risks of intraparenchymal hemorrhage, subarachnoid hemorrhage, or coronary heart disease among men or women.

CONCLUSIONS

We found an inverse association between seaweed intake and risk of total stroke, especially that from cerebral infarction, among Japanese men.

Elevated mycobacterium avium subsp. paratuberculosis (MAP) antibody titer in Japanese multiple sclerosis

To investigate whether antibody production against mycobacterium avium subsp. paratuberculosis (MAP) is related to clinical characteristics of multiple sclerosis (MS) and human leukocyte antigen (HLA) alleles, IgG antibody against three MAP peptides and two human peptides homologous to MAP were measured in sera from 103 MS patients and 50 healthy controls (HCs). MS patients had higher IgG levels against MAP2694_295-303 (MAP2694-IgG) than HCs, while the other antibodies were comparable. Multivariate analysis demonstrated that higher MAP2694-IgG titers were associated with higher EDSS scores, but not with HLA alleles or dairy product consumption. Immune response against MAP may worsen MS disability.

Peanut Consumption and Risk of Stroke and Ischemic Heart Disease in Japanese Men and Women: The JPHC Study

[Figure: see text].

Identification of Salty Dietary Patterns of the Japanese Macroregion

Objective

The traditional Japanese dietary pattern, “Washoku,” is considered to provide an ideal nutritional balance. However, it tends to have a high salt intake. To reduce population-level salt intake, it is important to review the overall dietary patterns over a wide area.

Methods

To identify dietary patterns with high salt intake, partial least squares regression analysis was conducted using population-based household survey data from 52 cities. Annual salt consumption was set as the target variable, and the annual purchase weight of 109 foods was set as the explanatory variable.

Result

At least three dietary patterns (traditional, urban, and local) accounted for more than 90% of the variation in salt consumption and 29% of the explanatory variables (food purchases). Traditional patterns explained the salt consumption and regional differences in energy and protein consumption; however, their relationship to fat consumption was weak. The results reconfirmed that “Washoku” has an ideal nutritional balance but has high salt intake. The distribution of scores for traditional Japanese food patterns was high in northeast Japan and low in southwest Japan, with a geographical gradient. This pattern is thought to have formed over a long period of time because of the influence of environmental factors, such as local climate.

Reproducibility and validity of food group intake in a short food frequency questionnaire for the middle-aged Japanese population

Purpose

The purpose of this study was to evaluate the reproducibility and validity of a short food frequency questionnaire (FFQ) for food group intake in Japan, the reproducibility and partial validity of which were previously confirmed for nutrients.

Methods

A total of 288 middle-aged healthy volunteers from 11 different areas of Japan provided nonconsecutive 3-day weighed dietary records (DRs) at 3-month intervals over four seasons. We evaluated reproducibility based on the first (FFQ1) and second (FFQ2) questionnaires and their validity against the DRs by comparing the intake of 20 food groups. Spearman’s rank correlation coefficients (SRs) were calculated between energy-adjusted intake from the FFQs and that from the DRs.

Results

The intake of 20 food groups estimated from the two FFQs was mostly equivalent. The median energy-adjusted SRs between the FFQ1 and FFQ2 were 0.61 (range 0.38–0.86) for men and 0.66 (0.45–0.84) for women. For validity, the median de-attenuated SRs between DRs and the FFQ1 were 0.51 (0.17–0.76) for men and 0.47 (0.23–0.77) for women. Compared with the DRs, the proportion of cross-classification into exact plus adjacent quintiles with the FFQ1 ranged from 58 to 86% in men and from 57 to 86% in women. According to the robust Z scores and the Bland–Altman plot graphs, the underestimation errors in the FFQ1 tended to be greater in individuals with high mean levels of consumption for meat for men and for other vegetables for both men and women.

Conclusion

The FFQ demonstrated high reproducibility and reasonable validity for food group intake. This questionnaire is short and remains appropriate for identifying associations between diet and health/disease among adults in Japan.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12199-021-00951-3.

Association Between Dietary Fish and PUFA Intake in Midlife and Dementia in Later Life: The JPHC Saku Mental Health Study

BACKGROUND

The relationship between midlife dietary habits and risk of dementia remains unclear.

OBJECTIVE

To investigate the association between dietary fish and n-3 polyunsaturated fatty acid (PUFA) consumption in midlife and risk of dementia in later life.

METHODS

This population-based cohort study assessed food frequency (average intake in 1995 and 2000) and cognition (2014-2015) in 1,127 participants (aged 45-64 in 1995). We used logistic regression analyses to calculate odds ratios (ORs) for dementia and mild cognitive impairment (MCI) diagnoses for consumption quartiles of fish, PUFA-rich fish, total n-3 PUFAs, total n-6 PUFAs, types of PUFAs, and n-3/n-6 PUFA ratio. Estimated ORs were adjusted for age; sex; education; smoking status; alcohol consumption frequency; physical activity; histories of cancer, myocardial infarction, and diabetes mellitus; and depression.

RESULTS

Significantly reduced risks of dementia over non-dementia (MCI plus cognitively normal) were observed in the second (OR = 0.43 (95% CI = 0.20-0.93)), third (OR = 0.22 (95% CI = 0.09-0.54)), and highest quartiles (OR = 0.39 (95% CI = 0.18-0.86)) for fish; the third (OR = 0.39 (95% CI = 0.16-0.92)) and highest quartiles (OR = 0.44 (95% CI = 0.19-0.98)) for eicosapentaenoic acid (EPA); the second (OR = 0.39 (95% CI = 0.18-0.84)), third (OR = 0.30 (95% CI = 0.13-0.70)), and highest quartiles (OR = 0.28 (95% CI = 0.12-0.66)) for docosahexaenoic acid (DHA); and the third (OR = 0.36 (95% CI = 0.16-0.85)) and highest quartiles (OR = 0.42 (95% CI = 0.19-0.95)) for docosapentaenoic acid (DPA).

CONCLUSION

High intake of fish in midlife might aid in preventing dementia.

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.

Association between meat intake and mortality due to all-cause and major causes of death in a Japanese population

PURPOSE

We examined the association between meat intake and mortality due to all-cause and major causes of death using a population-based cohort study in Japan.

METHODS

87,507 Japanese aged between 45 and 74 years old at 5-year follow-up study were followed for 14.0 years on average. Associations between meat intake and mortality risk were assessed using a Cox proportional hazards model.

RESULTS

A heavy intake of total meat was associated with a higher risk of all-cause mortality relative to the lowest quartile intake in men (Q4: HR,1.18; 95%CIs, 1.06-1.31). A higher intake of total meat was associated with a lower risk of stroke mortality in women (Q2: HR, 0.70; 95%CIs, 0.51-0.94, Q3: HR, 0.68; 95%CIs, 0.50-0.95, Q4: HR, 0.66; 95%CIs, 0.44-0.99). A heavy intake of red meat was also associated with all-cause mortality (Q4: HR, 1.13; 95%CIs, 1.02-1.26) and heart disease mortality (Q4: HR, 1.51; 95%CIs, 1.11-2.06) in men but not in women. Heavy intake of chicken was inversely associated with cancer mortality in men.

CONCLUSIONS

Heavy intakes of total and red meat were associated with an increase in all-cause and heart disease mortality in men, while total meat intake was associated with a lower risk of stroke mortality in women.

Association between meat and saturated fatty acid intake and lung cancer risk: The Japan Public Health Center-based prospective study

Red meat or saturated fatty acid (SFA) intake has been reported to increase lung cancer (LC) risk in several western countries. However, in Asia, studies on the relationship between meat and SFA intake with LC incidence are still relatively insufficient, and their conclusions are inconsistent. We investigated the association of meat and SFA intake with LC incidence in a population-based prospective cohort study in Japan. Cox regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for LC risk according to meat intake and SFA intake. A total of 73 187 participants (32 934 men and 40 253 women) aged 45 to 74 years participated in our study. During the follow-up period of 1 151 839 person-years (median, 16.0 year) from 1995 to 2013 for Cohort I and from 1998 to 2013 for Cohort II, 1315 (901 men and 414 women) newly diagnosed cases of LC were identified. In men, we found an adverse association between total red meat intake (HR and 95% CI: 1.25 [1.02-1.53]; P_trend = .008) and LC risk. Additionally, borderline statistically significant elevated risks of LC were seen with high intake of unprocessed red meat and processed red meat. However, no positive association between total red meat intake and LC risk was observed in women. In contrast, poultry and fish intake were not associated with LC risk in either men or women. We concluded that a high total intake of total red meat was associated with moderately elevated LC risk in men.

Data-Driven Dietary Patterns and Diet Quality Scores: Reproducibility and Consistency in Sex and Age Subgroups of Poles Aged 15-65 Years

This study aimed to assess: (i) the test–retest reproducibility of identification of data-driven dietary patterns (DPs) derived using a Principal Component Analysis (PCA) and hypothesis-driven DPs (diet quality scores); (ii) the consistency of data-driven DPs with diet quality scores in sex and age subgroups of Poles aged 15–65 years. The study involved 504 subjects (55.6% of females). Data on food consumption frequency (33 food items) were collected twice with a two-week interval using the Dietary Habits and Nutrition Beliefs Questionnaire (KomPAN^®) in a self-administered version (test and retest). Two major data-driven DPs (‘Prudent’ and ‘Western’) were identified in the total sample, sex groups and four age groups separately from test and retest data. Two diet quality scores were analysed: Pro-Healthy-Diet-Index-10 (pHDI-10) and Non-Healthy-Diet-Index-14 (nHDI-14). Tucker’s congruence coefficient indicated fair-to-good similarity of data-driven DPs between test and retest for all study subgroups, except for males. Across study subgroups, the intraclass correlation coefficient (ICC) between the test and retest ranged from 0.56 to 0.86 for ‘Prudent’ DP and 0.57 to 0.82 for ‘Western’ DP, with the lowest values in males. The ICC (test vs. retest) ranged from 0.84 to 0.88 for pHDI-10 and 0.75 to 0.88 for nHDI-14. Comparing the data-driven DPs and diet quality scores, the Spearman’s correlations ranged from 0.63 to 0.93 between ‘Prudent’ DP and pHDI-10, and from 0.60 to 0.81 between ‘Western’ DP and nHDI-14. The test–retest reproducibility of data-driven DPs and diet quality scores and their consistency were acceptable in most of the study subgroups, with a tendency to be higher for pro-health than unhealthy DPs. Data-driven DPs were more reproducible in females than males. The reproducibility of diet quality scores tended to be better in males than females and was the highest in 25–44-year-olds. The KomPAN^® questionnaire can be recommended to use data-driven DPs and diet quality scores to describe the habitual diet in people aged 15–65 years.

Soy and isoflavone consumption and subsequent risk of prostate cancer mortality: the Japan Public Health Center-based Prospective Study

BACKGROUND

Although many epidemiological studies have reported the preventive effects of soy products and isoflavones on prostate cancer, our previous studies reported that the association between soy and isoflavones and prostate cancer incidence differed according to stage. It is more important to identify modifiable risk factors related to lethal prostate cancer. Here, we investigated the association between soy, soy products and isoflavones intake and prostate cancer mortality, in a prospective study in Japan.

METHODS

We conducted a population-based prospective study in 43 580 Japanese men with no history of cancer or cardiovascular disease (aged 45-74 years). Participants completed a validated questionnaire which included 138 food items. We followed participants from 1995 to 2016. Hazard ratios (HRs) and 95% confidence intervals (CIs) of prostate cancer mortality were calculated according to quintiles of soy products and isoflavones intake, using Cox hazard proportional hazards regression.

RESULTS

During 16.9 years follow-up, we registered 221 deaths from prostate cancer. Isoflavones and soy products intake was associated with an increased risk of prostate cancer death, with multivariate HRQ5 vs. Q1=1.39, 95% CI = 0.87-2.20, p for trend = 0.04 for isoflavones and multivariate HRQ5 vs. Q1=1.76, 95% CI = 1.10-2.82, p for trend = 0.04 for soy food.

CONCLUSIONS

Our study suggested that high intake of soy and isoflavones might increase the risk of prostate cancer mortality.

Impact of seaweed intake on health

Seaweeds contain minerals, vitamins, soluble dietary fibers, and flavonoids, which are regarded as preventive agents against lifestyle-related diseases. Seaweeds are consumed commonly in East Asian countries including Japan. Thus, intake of seaweeds might contribute to Japanese longevity via prevention of lifestyle-related diseases. Recently, two large Japanese cohort studies have reported the association of seaweed intake with reduced risk of cardiovascular diseases. On the other hand, seaweeds also contain iodine and heavy metals such as arsenic species, which are considered to have adverse effects on health. We here reviewed studies of the association between seaweed intake and mortality from or incidence of cancer and cardiovascular diseases, and their risk factors such as blood pressure or serum lipids. We also summarized the adverse effects of iodine and arsenic species in seaweeds. Although seaweeds have not been widely consumed in Western countries, dietary diversification and an increased proportion of immigrants from East Asia may increase seaweed consumption in those countries. Further epidemiological studies including observational and interventional studies are necessary to clarify the effects of seaweeds on disease and health.

The reliability and relative validity of predefined dietary patterns were higher than that of exploratory dietary patterns in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam population

The aim of this study was to assess the ability of the FFQ to describe reliable and valid dietary pattern (DP) scores. In a total of 134 participants of the European Prospective Investigation into Cancer and Nutrition-Potsdam study aged 35–67 years, the FFQ was applied twice (baseline and after 1 year) to assess its reliability. Between November 1995 and March 1997, twelve 24-h dietary recalls (24HDR) as reference instrument were applied to assess the validity of the FFQ. Exploratory DP were derived by principal component analyses. Investigated predefined DP were the Alternative Healthy Eating Index (AHEI) and two Mediterranean diet indices. From dietary data of each FFQ, two exploratory DP were retained, but differed in highly loading food groups, resulting in moderate correlations (r 0·45–0·58). The predefined indices showed higher correlations between the FFQ (r(AHEI) 0·62, r(Mediterranean Diet Pyramid Index (MedPyr)) 0·62 and r(traditional Mediterranean Diet Score (tMDS)) 0·51). From 24HDR dietary data, one exploratory DP retained differed in composition to the first FFQ-based DP, but showed similarities to the second DP, reflected by a good correlation (r 0·70). The predefined DP correlated moderately (r 0·40–0·60). To conclude, long-term analyses on exploratory DP should be interpreted with caution, due to only moderate reliability. The validity differed extensively for the two exploratory DP. The investigated predefined DP showed a better reliability and a moderate validity, comparable to other studies. Within the two Mediterranean diet indices, the MedPyr performed better than the tMDs in this middle-aged, semi-urban German study population.

Adherence to a Mediterranean diet is associated with a lower risk of later-onset Crohn's disease: results from two large prospective cohort studies

OBJECTIVE

To examine the relationship between Mediterranean diet and risk of later-onset Crohn's disease (CD) or ulcerative colitis (UC).

DESIGN

We conducted a prospective cohort study of 83 147 participants (age range: 45-79 years) enrolled in the Cohort of Swedish Men and Swedish Mammography Cohort. A validated food frequency questionnaire was used to calculate an adherence score to a modified Mediterranean diet (mMED) at baseline in 1997. Incident diagnoses of CD and UC were ascertained from the Swedish Patient Register. We used Cox proportional hazards modelling to calculate HRs and 95% CI.

RESULTS

Through December of 2017, we confirmed 164 incident cases of CD and 395 incident cases of UC with an average follow-up of 17 years. Higher mMED score was associated with a lower risk of CD (P_trend=0.03) but not UC (P_trend=0.61). Compared with participants in the lowest category of mMED score (0-2), there was a statistically significant lower risk of CD (HR=0.42, 95% CI 0.22 to 0.80) but not UC (HR=1.08, 95% CI 0.74 to 1.58). These associations were not modified by age, sex, education level, body mass index or smoking (all P_interaction >0.30). The prevalence of poor adherence to a Mediterranean diet (mMED score=0-2) was 27% in our cohorts, conferring a population attributable risk of 12% for later-onset CD.

CONCLUSION

In two prospective studies, greater adherence to a Mediterranean diet was associated with a significantly lower risk of later-onset CD.

Co-consumption of Vegetables and Fruit, Whole Grains, and Fiber Reduces the Cancer Risk of Red and Processed Meat in a Large Prospective Cohort of Adults from Alberta's Tomorrow Project

We examined whether co-consumption of red and processed meat with key foods items and food constituents recommended for cancer prevention (vegetables and fruit, whole grains, and fiber) mitigates cancer incidence. In a prospective cohort of 26,218 adults aged 35–69 years at baseline, dietary intake was collected through 124-item past-year food frequency questionnaire. Incidence of all-cause and 15 cancers previously linked to red and processed meat intake was obtained through data linkage with a cancer registry (average follow-up 13.5 years). Competing risk Cox Proportional Hazard models estimated cancer risk and Accelerated Failure Time models estimated time-to-cancer occurrence for different combinations of intake levels while considering mortality from vital statistics and established confounders. Co-consumption of low vegetables and fruit intake with high processed meat was associated with higher incidence of all-cause and 15 cancers (men: HR = 1.85, 1.91; women: HR = 1.44, 1.49) and accelerated time-to-cancer occurrence (men: 6.5 and 7.1 years and women: 5.6 and 6.3 years, respectively), compared to high vegetables and fruit with low processed meat intake. Less pronounced and less consistent associations were observed for whole grains and fiber and for red meat. The findings provide initial evidence toward refining existing cancer prevention recommendations to optimize the intake and combination of foods in the general adult population.

Skipping breakfast before and during early pregnancy and incidence of gestational diabetes mellitus: the Japan Environment and Children's Study

BACKGROUND

There is little evidence linking breakfast skipping to the incidence of gestational diabetes mellitus (GDM).

OBJECTIVES

We aimed to evaluate the prospective association of breakfast consumption with the incidence of GDM.

METHODS

A total of 103,099 pregnancies were registered during study enrollment (January 2011 to March 2014), involving 97,454 pregnant women from 15 areas across Japan. Singleton pregnant women free of GDM, stroke, heart disease, cancer, and type 1 or type 2 diabetes at the study enrollment were eligible for analysis. We used a self-administered questionnaire to obtain data on demographic information, socioeconomic status, self-rated health status, disease history, lifestyle, and dietary habits of each woman at study enrollment. A semiquantitative FFQ was used for dietary assessment. We used logistic regression to obtain the OR of GDM in relation to breakfast consumption.

RESULTS

Among 84,669 pregnant women for analysis, 1935 cases of GDM were documented. After adjustment for potential confounding factors including prepregnancy BMI, the multivariable-adjusted ORs of GDM for women who consumed breakfast 5-6 times/wk, 3-4 times/wk, and 0-2 times/wk were 1.09 (95% CI: 0.93, 1.27), 1.14 (95% CI: 0.96, 1.34), and 1.21 (95% CI: 1.05, 1.41), respectively, compared with daily breakfast eaters. The association appeared to be dose dependent (P-trend = 0.006) and was not significantly modified by prepregnancy BMI.

CONCLUSIONS

Breakfast consumption <3 times/wk before and during early pregnancy, compared with daily consumption, was associated with an increased odds of developing GDM.

Reproducibility and Validity of A Posteriori Dietary Patterns: A Systematic Review

The effective use of dietary patterns (DPs) remains limited. There is a need to assess their consistency over multiple administrations of the same dietary source, different dietary sources, or across different studies. Similarly, their generalizability should be based on a previous assessment of DP construct validity. However, to date, no systematic reviews of reproducibility and validity of a posteriori DPs have been carried out. In addition, several methodological questions related to their identification are still open and prevent a fair comparison of epidemiological results on DPs and disease. A systematic review of the literature on the PubMed database was conducted. We identified 218 articles, 64 of which met the inclusion criteria. Of these, the 38 articles dealing with reproducibility and relative and construct validity of DPs were included. These articles (published in 1999-2017, 53% from 2010 onwards) were based on observational studies conducted worldwide. The 14 articles that assessed DP reproducibility across different statistical solutions examined different research questions. Included were: the number of food groups or subjects; input variable format (as well as adjustment for energy intake); algorithms and the number of DPs to retain in cluster analysis; rotation method; and score calculation in factor analysis. However, we identified at most 3 articles per research question on DP reproducibility across statistical solutions. From another 15 articles, reproducibility of DPs over shorter (≤1 y) time periods was generally good and higher than DP relative validity (as measured across different dietary sources). Confirmatory factor analysis was used in 15 of the included articles. It provided reassuring results in identifying valid dietary constructs characterizing the populations under consideration. Based on the available evidence, only suggestive conclusions can be derived on reproducibility across different statistical solutions. Nevertheless, most identified DPs showed good reproducibility, fair relative validity, and good construct validity.

Dietary patterns of adults and their associations with Sami ethnicity, sociodemographic factors, and lifestyle factors in a rural multiethnic population of northern Norway - the SAMINOR 2 clinical survey

Background

Few population-based studies have assessed dietary behaviors in the rural multiethnic population of Northern Norway. The present study determined dietary patterns and investigated their association with Sami ethnicity, sociodemographic factors, and lifestyle factors in a multiethnic population in rural Northern Norway.

Methods

This cross-sectional study included 4504 participants of the SAMINOR 2 Clinical Survey (2012–2014) aged 40–69 years. All participants completed a lifestyle and food frequency questionnaire. Dietary patterns were determined using principal component analysis. Associations between food patterns and ethnicity, sociodemographic factors, and lifestyle factors were examined by multiple linear regression.

Results

Six dietary patterns were identified that accounted for 28% of the variability in food intake in the study sample: ‘processed meat/westernized’, ‘fish/traditional’, ‘fruit/vegetables’, ‘reindeer/traditional’, ‘bread and sandwich spreads’, and ‘sweets and bakery goods’. The ‘reindeer/traditional’ pattern was most common among the inland Sami population. The ‘fish/traditional’ pattern was most common among costal multiethnic Sami and least common among inland Sami and among women independent of ethnicity. The ‘fish/traditional’ pattern was also positively associated with older age, high education level, small household size, and smoking. Adherence to the ‘processed meat/westernized’ pattern was lower among inland Sami than inland/coastal non-Sami; no ethnic differences in adherence to this pattern were found between costal multiethnic Sami and inland/coastal non-Sami. Unhealthy lifestyle factors, like low physical activity level and smoking, and younger age were mainly associated with the ‘processed meat/westernized’ pattern, whereas socioeconomic factors like low education, low gross annual household income, and large household size were related to the ‘sweets and bakery goods’ pattern. Male gender, low education level, and smoking were associated with the ‘bread and sandwich spreads’ pattern. The ‘fruit/vegetables’ pattern was characterized by healthy dietary choices and a health-conscious lifestyle, and was more common in women with a high education level and income.

Conclusions

Adherence to the six identified dietary patterns was characterized by different sociodemographic and lifestyle factors. Ethnicity, in combination with geographical region of residence, was associated with dietary behaviors. This study provides knowledge that will be useful in future studies on dietary patterns related to chronic diseases in the rural population of Northern Norway.

Seaweed intake and risk of cardiovascular disease: the Japan Public Health Center-based Prospective (JPHC) Study

BACKGROUND

The minerals, vitamins, soluble dietary fibers, and flavonoids of seaweed are protective for preventing cardiovascular diseases. However, the association between seaweed intake and risk of cardiovascular disease has not been established.

OBJECTIVES

We examined the dietary intake of seaweed and its impact upon stroke and ischemic heart disease risk among a Japanese study population.

METHODS

We surveyed 40,707 men and 45,406 women from 2 large cohorts (age range: 40-69 y). Seaweed intake was determined by FFQ at baseline (1990-1994). Incidences of stroke and ischemic heart disease were ascertained until the end of 2009 (Cohort I) or 2012 (Cohort II). Sex-specific cardiovascular disease HRs (95% CIs) were estimated using Cox proportional hazard models after stratification by area and adjustment for cardiovascular disease risk and dietary factors.

RESULTS

During 1,493,232 person-years of follow-up, 4777 strokes (2863 ischemic stroke, 1361 intraparenchymal hemorrhages, and 531 subarachnoid hemorrhages) and 1204 ischemic heart disease cases were identified. Among men, significant multivariable HRs (95% CIs) for almost daily consumption compared with almost no consumption of seaweed were seen in ischemic heart disease [0.76 (0.58, 0.99); P-trend = 0.04] and total cardiovascular diseases [0.88 (0.78, 1.00); P-trend = 0.08]. Among women, such inverse associations were 0.56 (0.36, 0.85; P-trend = 0.006) for ischemic heart disease and 0.89 (0.76, 1.05; P-trend = 0.10) for total cardiovascular diseases. No significant associations were observed between seaweed intake and risk of total stroke or stroke types among either men or women.

CONCLUSIONS

Seaweed intake was inversely associated with risk of ischemic heart disease.

Environmental risk factors for multiple sclerosis in Japanese people

BACKGROUND

The prevalence of multiple sclerosis (MS) has been increasing worldwide in recent years, especially among females. The same increasing trends are even observed in East Asian countries, where the prevalence of MS is relatively low compared with Northern European ancestries. Whether the environmental risk factors for MS are shared between Asian and North European ancestries, and the types of environmental factors that contribute to the low and recent increase in MS prevalence in Asian countries remain unknown. This study provides the first comprehensive survey of environmental risks for MS in East Asia.

METHODS

Patients with MS were recruited from the Department of Neurology at Kyushu University Hospital, Japan between 01 April 2017 and 31 March 2018. Healthy controls (HCs) were recruited by public notification. All participants were residents of Kyushu Island and were required to complete medical history and lifestyle questionnaires. Dietary data were collected using a Food Frequency Questionnaire comprising intake of approximately 140 food and beverage items in the past 1 year. One hundred and three patients with MS and 124 healthy controls (HCs) completed the questionnaires. Age at onset and disability score measured by the Kurtzke Expanded Disability Status Scale (EDSS) were obtained from medical records.

RESULTS

Frequency of obesity (body mass index ≥25 kg/m²) at present time was higher in MS patients than in HCs (19.4% vs. 7.4%, p = 0.009), while body mass index at age 18-20 years did not differ between the two groups. Frequency of current or ex-smokers was higher in MS patients than in HCs (50.5% vs. 22.8%, p < 0.0001) and disability measured by the EDSS was more severe in MS patients with active smoking history than in patients without such history (p = 0.006 after adjusting for sex). Passive smoking after age 16 years was also a risk factor for MS (odds ratio: 1.31, 95% confidence interval: 1.05-1.63, p = 0.015). Longer sunlight exposure in early childhood was a protective factor for MS (odds ratio: 0.65 during summer and 0.71 during winter at age 6-10 years; 0.71 during summer and 0.72 during winter at age 11-15 years). MS patients had earlier age of menarche than HCs (mean: 12.4 years vs. 12.9 years, p = 0.031). Intake of grains was lower in MS patients than in HCs, with intake of rice in particular being significantly lower in MS patients than in HCs (mean: 235.2 g/day vs. 280.6 g/day, p = 0.006). Previously reported foods associated with MS in Northern European ancestries were not replicated in Japanese people.

CONCLUSION

Smoking and earlier age of menarche are positively associated and sunlight exposure in early childhood is negatively associated with MS in Japanese people as shown in Caucasians. Intake of steamed short-grain white rice, a staple food in Japan, is newly found to be negatively associated with MS in Japanese people. Although the causality is unclear because the participants were prevalent cases, these environmental factors may be involved in the rising prevalence of MS in Japanese females.

Meat subtypes and colorectal cancer risk: A pooled analysis of 6 cohort studies in Japan

Red meat and processed meat have been suggested to increase risk of colorectal cancer (CRC), especially colon cancer. However, it remains unclear whether these associations differ according to meat subtypes or colon subsites. The present study addressed this issue by undertaking a pooled analysis of large population-based cohort studies in Japan: 5 studies comprising 232 403 participants (5694 CRC cases) for analysis based on frequency of meat intake, and 2 studies comprising 123 635 participants (3550 CRC cases) for analysis based on intake quantity. Study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using the Cox proportional hazards model and then pooled using the random effect model. Comparing the highest vs lowest quartile, beef intake was associated with an increased risk of colon cancer in women (pooled HR 1.20; 95% CI, 1.01-1.44) and distal colon cancer (DCC) risk in men (pooled HR 1.30; 95% CI, 1.05-1.61). Frequent intake of pork was associated with an increased risk of distal colon cancer in women (pooled HR 1.44; 95% CI, 1.10-1.87) for "3 times/wk or more" vs "less than 1 time/wk". Frequent intake of processed red meat was associated with an increased risk of colon cancer in women (pooled HR 1.39; 95% CI, 0.97-2.00; P trend = .04) for "almost every day" vs "less than 1 time/wk". No association was observed for chicken consumption. The present findings support that intake of beef, pork (women only), and processed red meat (women only) might be associated with a higher risk of colon (distal colon) cancer in Japanese.

A cross-sectional study of the associations between the traditional Japanese diet and nutrient intakes: the NILS-LSA project

Background

Although our previous study using a food frequency questionnaire simulated nutritional characteristics of the traditional Japanese diet, this issue has not been sufficiently evaluated. This study was conducted to examine the relationship between the traditional Japanese diet and nutrient density (ND).

Methods

A cross-sectional study employing the dietary record method was conducted among 2221 community-dwelling Japanese adults (40–88 years) living in Aichi Prefecture, Japan, in 2006–2008. Based on previous studies, a 9-component Japanese Diet Index (JDI) and a 12-component modified JDI (mJDI₁₂) were defined. To develop a new weighted index, a multiple linear regression model was used to select food components which were significantly associated with an ND score (integrated by 11 nutrient components) from the mJDI₁₂ and weight them. Correlation analyses were performed between JDI, mJDI₁₂, the new weighted JDI score and the ND score and its 11 nutrient components. The findings were validated with data from 2008 to 2010 by assessing the associations between the JDIs scores and the ND score.

Results

Scores of the JDI and mJDI₁₂ were positively correlated with the ND score (corresponding Spearman’s ρ [95% confidence interval; CI], 0.34 [0.31, 0.38] and 0.44 [0.41, 0.48], respectively; P < 0.05 for both). Among the mJDI₁₂, 9 food components (rice, fish and shellfish, green and yellow vegetables, seaweed, green tea, beef and pork, soybeans and soybean foods, fruit, and mushrooms) significantly associated with the ND score. All of these 9 components were weighted and a new weighted JDI (wJDI₉) was developed. The wJDI₉ score was also positively correlated with the ND score (Spearman’s ρ [95% CI] = 0.61 [0.58, 0.64]; P < 0.05). However, scores for all 3 indices were positively correlated with sodium intake. The wJDI₉ score obtained using dietary record data from 2008 to 2010 was also positively correlated with the ND score (Spearman’s ρ [95% CI] = 0.61 [0.58, 0.64]; P < 0.05).

Conclusions-

Adhering to a traditional Japanese diet as defined by the JDI was associated with good ND. Furthermore, the modified indices (mJDI₁₂ and wJDI₉) had a higher performance for ND. However, all of the indices were correlated with high sodium intake.

Electronic supplementary material

The online version of this article (10.1186/s12937-019-0468-9) contains supplementary material, which is available to authorized users.

Diet quality and depression risk in a Japanese population: the Japan Public Health Center (JPHC)-based Prospective Study

The association of overall diet quality based on the Japanese Food Guide Spinning Top with risk of depression is not known. This prospective cohort study aimed to determine whether higher adherence to the Japanese food guide reduced the risk of depression. Of 12,219 residents enrolled at baseline, we extracted 1,112 participants who completed a 5-year follow-up (1995) and participated in a mental health screening (2014–2015). Diet quality was scored based on adherence to the Japanese food guide and the ratio of white to red meat according to the Alternative Healthy Index and ranged from 0 (worst) to 80 (best). We calculated odds ratios and 95% confidence intervals for current psychiatrist-diagnosed depression per quartile of total score and of eight component scores with the lowest quartile as reference. Mean age of the participants was 73 years and 59% were women. Total diet quality score was not significantly associated with risk of depression 20 years after the baseline assessment. Among the eight components on the diet quality score, there was a significantly reduced risk for the highest quartile of the white to red meat ratio score. In conclusion, our results do not indicate that higher adherence to the Japanese food guide prevents depression.

A Systematic Review of Principal Component Analysis-Derived Dietary Patterns in Japanese Adults: Are Major Dietary Patterns Reproducible Within a Country?

Principal component analysis (PCA) has been widely used in nutritional epidemiology to derive dietary patterns. However, although PCA-derived dietary patterns are population-dependent, their reproducibility in different populations is largely unexplored. We aimed to investigate whether major dietary patterns are consistently identified among different populations within a country and, if so, how similar these dietary patterns are. We conducted a systematic review of PCA-derived dietary patterns in Japanese adults using PubMed and Web of Science for English articles and Ichushi-Web and CiNii databases for Japanese articles. We assessed the reproducibility of major dietary patterns using congruence coefficients (CCs), with values ≥0.80 considered to represent fair similarity. From 65 articles (80 studies) included in this review, 285 different dietary patterns were identified. Based on the names of these patterns, major dietary patterns were Western (n = 34), Japanese (n = 12), traditional (n = 10), traditional Japanese (n = 9), healthy (n = 18), and prudent (n = 9) patterns. When assessment was limited to high-quality data (i.e., studies based on a sample size ≥200 and use of a validated dietary assessment questionnaire or multiple-day dietary record), the median CC was low for Western (0.44), traditional (0.59), and traditional Japanese (0.31) patterns. Conversely, the median CC was 0.89 for healthy, 0.86 for prudent, and 0.80 for Japanese patterns; and the proportion of pairs with a CC ≥0.80 was 87.3%, 64.3%, and 50.0%, respectively. Characteristics shared among these 3 dietary patterns included higher intakes of mushrooms, seaweeds, vegetables, potatoes, fruits, pulses, and pickles. In conclusion, this systematic review showed that some of the major dietary patterns are relatively reproducible in different populations within a country, whereas others are not. This highlights the importance of careful interpretation of PCA-derived dietary patterns. Our findings in Japan should be confirmed in different countries and globally. This study was registered at https://www.crd.york.ac.uk/prospero/ as CRD42018087669.

Parents' Reports of Preschoolers' Diets: Relative Validity of a Food Frequency Questionnaire and Dietary Patterns

The accurate assessment of food consumption is crucial in nutritional studies. Since modern nutrition science has become more interested in diet as a whole, studies validating food frequency questionnaires (FFQs) and exploratory dietary patterns are needed. We aimed at examining the relative validity of a 47-item FFQ against three-day food records among three- to six-year-old Finnish children, as well as investigating the consistency of the dietary patterns derived using the principal component analysis (PCA), with food record and FFQ data as inputs. We conducted the PCA without forcing the food record data to match the FFQ items. Altogether, 75% or more of the participants were classified into the same or adjacent quarter of vegetables and fruits as well as sugary food consumption. Furthermore, the intake of folate and vitamin C increased linearly in the quarters of vegetable and fruit consumption, as did the intake of sucrose in quarters of sugary food consumption. Three fairly similar dietary patterns were identified from food records and FFQ data. Concerning the patterns, more than 70% of the participants were classified into the same or adjacent quarter. However, the Spearman correlation coefficients between the respective pattern scores were low (0.25–0.33). The FFQ showed acceptable validity when ranking food group consumption compared to food records. Additionally, the FFQ-derived dietary patterns were consistent with those derived using food record data.

Dietary Patterns and Their Sociodemographic and Lifestyle Determinants in Switzerland: Results from the National Nutrition Survey menuCH

From a public health perspective, determinants of diets are crucial to identify, but they remain unclear in Switzerland. Hence, we sought to define current dietary patterns and their sociodemographic and lifestyle determinants using the national nutrition survey menuCH (2014⁻2015, n = 2057). First, we applied multiple factorial analysis and hierarchical clustering on the energy-standardised daily consumption of 17 food categories. Four dietary patterns were identified ("Swiss traditional": high intakes of dairy products and chocolate, n = 744; "Western 1": soft drinks and meat, n = 383; "Western 2": alcohol, meat and starchy, n = 444; and "Prudent": n = 486). Second, we used multinomial logistic regression to examine the determinants of the four dietary patterns: ten sociodemographic or lifestyle factors (sex, age, body mass index, language region, nationality, marital status, income, physical activity, smoking status, and being on a weight-loss diet) were significantly associated with the dietary patterns. Notably, belonging to the French- and Italian-speaking regions of Switzerland increased the odds of following a "Prudent" diet (Odds ratio [95% confidence interval]: 1.92 [1.45⁻2.53] and 1.68 [0.98⁻2.90], respectively) compared to the German-speaking regions. Our findings highlight the influence of sociodemographic and lifestyle parameters on diet and the particularities of the language regions of Switzerland. These results provide the basis for public health interventions targeted for population subgroups.

Exploratory dietary patterns: a systematic review of methods applied in pan-European studies and of validation studies

Besides a priori approaches, using previous knowledge about food characteristics, exploratory dietary pattern (DP) methods, using data at hand, are commonly applied. This systematic literature review aimed to identify exploratory methods on DP in pan-European studies and to inform the development of the DEterminants of DIet and Physical ACtivity (DEDIPAC) toolbox of methods suitable for use in future European studies. The search was conducted in three databases on prospective studies in healthy, free-living people across the whole life span. To identify validated DP methods, an additional search without regional restrictions was conducted. Studies including at least two European countries were retained. The search resulted in six pan-European studies applying principal component/factor analysis (PC/FA) (n 5) or cluster analysis (n 2). The criteria to retain PC/factors ranged from the application of the eigenvalue>1 criterion, the scree plot and/or the interpretability criterion. Furthermore, seven validation studies were identified: DP, derived by PC/FA (n 6) or reduced rank regression (RRR) (n 1) were compared using dietary information from FFQ (n 6) or dietary history (n 1) as study instrument and dietary records (n 6) or 24-h dietary recalls (n 1) as reference. The correlation coefficients for the derived DP ranged from modest to high. To conclude, PC/FA was predominantly applied using the eigenvalue criterion and scree plot to retain DP, but a better description of the applied criteria is highly recommended to enable a standardised application of the method. Research gaps were identified for the methods cluster analysis and RRR, as well as for validation studies on DP.

The Validity and Reproducibility of Dietary Non-enzymatic Antioxidant Capacity Estimated by Self-administered Food Frequency Questionnaires

Background

High dietary non-enzymatic antioxidant capacity (NEAC) has been inversely related to the incidence of degenerative diseases. However, few studies have investigated the validity and reproducibility of dietary NEAC estimated from a food frequency questionnaire (FFQ). We assessed the validity and reproducibility of FFQ-based dietary NEAC against a dietary record (DR).

Methods

Participants were 244 men and 253 women who completed a 28-day DR and FFQs. NEAC for each food item was estimated according to available databases of antioxidant capacity, as measured by ferric reducing-antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and total radical-trapping antioxidant parameter (TRAP). Using Spearman’s rank correlation coefficients (CCs), we assessed the validity for dietary NEACs from a 28-day DR and a FFQ, and the reproducibility for them from two FFQs administered at a 1-year interval. Additionally, joint classification and the Bland-Altman method were applied to assess agreement between the two methods.

Results

Regarding validation, deattenuated CCs for the energy-adjusted overall dietary NEACs between FFQ and DR for FRAP, ORAC, and TRAP were 0.52, 0.54, and 0.52, respectively, for all subjects. Extreme miscategorization rates by joint classification analysis were 2% for FRAP and ORAC and 1% for TRAP. Regarding reproducibility, CCs between the energy-adjusted dietary NEACs from two FFQs were 0.64 for FRAP and 0.65 for ORAC and TRAP.

Conclusion

The validity and reproducibility of dietary NEAC of total food from the FFQ were moderate. Estimations of dietary NEAC using FFQ would be useful in studying disease relationships by categorizing habitual dietary NEAC.

Variation in Men's Dietary Intake Between Occupations, Based on Data From the Japan Environment and Children's Study

There has been increasing interest in dietary health promotion in the workplace. Although many previous studies have focused on dietary habits in specific occupations, variation between occupational groups requires clarification. The present study aimed to examine differences in food and nutrient intake between occupational groups, using detailed classification. A cross-sectional study was conducted using data from the Japan Environment and Children’s Study. The study included 38,721 employed Japanese expectant fathers aged between 20 and 65 years. Dietary intake was assessed using a food frequency questionnaire. Occupations were categorized into 11 categories according to the Japan Standard Occupational Classification. Analysis of variance and analysis of covariance were performed to compare dietary intake of occupational groups. Logistic regression analysis was performed to examine the differences in adherence to dietary recommendations across occupations. Dietary intake differed significantly between occupations. Specific dietary intake was observed in security and agricultural workers, who tended to exhibit higher consumption levels for numerous foods and nutrients. In addition, relative to other workers, security workers showed higher intake of dairy products and calcium, and agricultural workers consumed larger amounts of pickles and salt. The study categorized occupations into detailed categories using the Japan Standard Occupational Classification, which facilitated the clarification of overall dietary trends across occupations and identification of specific dietary characteristics in individual occupations. The findings could aid in workplace health promotion.

Dietary patterns and prostate cancer risk in Japanese: the Japan Public Health Center-based Prospective Study (JPHC Study)

PURPOSE

The development of prostate cancer may be impacted by environmental factors, including diet. The aim of this study was to evaluate the association between dietary patterns and risk of prostate cancer in a large prospective cohort study among Japanese men.

METHODS

A total of 43,469 men who participated in the Japan Public Health Center-based Prospective Study were followed from 1995 to 1998 to the end of 2012, during which 1,156 cases of prostate cancer were newly identified. Dietary intake was assessed using a validated food frequency questionnaire in the 5-year follow-up survey.

RESULTS

Three major dietary patterns were derived using exploratory factors analysis: prudent, westernized, and traditional dietary patterns. The westernized dietary pattern was associated with a higher risk of total prostate cancer (HR: 1.22; 95% CI 1.00-1.49; p trend = 0.021), localized cancer (HR: 1.24; 95% CI 0.97-1.57; p trend = 0.045), and advanced cancer (HR: 1.23; 95% CI 0.82-1.84; p trend = 0.233). The prudent dietary pattern was associated with a lower risk of total and localized prostate cancer, with respective multivariable HRs for the highest and lowest quintiles of 0.71 (95% CI 0.50-1.02; p trend = 0.037) and 0.63 (95% CI 0.38-1.03; p trend = 0.048) among subjects detected by subjective symptoms. No association was found between the traditional dietary pattern and prostate cancer risk among our subjects.

CONCLUSION

Our results suggest that a western-style diet may lead to a higher risk of prostate cancer in the total population, whereas the prudent diet contributes to a lower risk among subjects detected by subjective symptoms.

Dietary Patterns Are Associated with Cardiovascular and Cancer Mortality among Swiss Adults in a Census-Linked Cohort

Defining dietary guidelines requires a quantitative assessment of the influence of diet on the development of diseases. The aim of the study was to investigate how dietary patterns were associated with mortality in a general population sample of Switzerland. We included 15,936 participants from two population-based studies (National Research Program 1A (NRP1A) and Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA)—1977 to 1993) who fully answered a simplified 24-h dietary recall. Mortality data were available through anonymous record linkage with the Swiss National Cohort (follow-up of up to 37.9 years). Multiple correspondence analysis and hierarchical clustering were used to define data-driven qualitative dietary patterns. Mortality hazard ratios were calculated for all-cause, cancer and cardiovascular mortality using Cox regression. Two patterns were characterized by a low dietary variety (“Sausage and Vegetables”, “Meat and Salad”), two by a higher variety (“Traditional”, “High-fiber foods”) and one by a high fish intake (“Fish”). Males with unhealthy lifestyle (smokers, low physical activity and high alcohol intake) were overrepresented in the low-variety patterns and underrepresented in the high-variety and “Fish” patterns. In multivariable-adjusted models, the “Fish” (hazard ratio = 0.82, 95% CI (0.68–0.99)) and “High-fiber foods” (0.85 (0.72–1.00)) patterns were associated with lower cancer mortality. In men, the “Fish” (0.73 (0.55–0.97)) and “Traditional” (0.76 (0.59–0.98)) patterns were associated with lower cardiovascular mortality. In summary, our results support the notion that dietary patterns affect mortality and that these patterns strongly cluster with other health determinants.

Impact of Alcohol Intake and Drinking Patterns on Mortality From All Causes and Major Causes of Death in a Japanese Population

BACKGROUND

We examined the associations of alcohol consumption and liver holidays with all-cause mortality and with mortality due to cancer, heart disease, cerebrovascular disease, respiratory disease, and injury using a large-scale prospective study in Japan.

METHODS

We followed 102,849 Japanese who were aged between 40 and 69 years at baseline for 18.2 years on average, during which 15,203 deaths were reported. Associations between alcohol intake and mortality risk were assessed using a Cox proportional hazards model, with analysis by the number of liver holidays (in which a person abstains from drinking for several days a week).

RESULTS

A J-shaped association was observed between alcohol intake and total mortality in men (nondrinkers: reference; occasional drinkers: hazard ratio [HR] 0.74; 95% confidence interval [CI], 0.68-0.80; 1-149 g/week: HR 0.76; 95% CI, 0.71-0.81; 150-299 g/week: HR 0.75; 95% CI, 0.70-0.80; 300-449 g/week: HR 0.84; 95% CI, 0.78-0.91; 450-599 g/week: HR 0.92; 95% CI, 0.83-1.01; and ≥600 g/week: HR 1.19; 95% CI, 1.07-1.32) and in women (nondrinkers: reference; occasional: HR 0.75; 95% CI, 0.70-0.82; 1-149 g/week: HR 0.80; 95% CI, 0.73-0.88; 150-299 g/week: HR 0.91; 95% CI, 0.74-1.13; 300-449 g/week: HR 1.04; 95% CI, 0.73-1.48; and ≥450 g/week: HR 1.59; 95% CI, 1.07-2.38). In current drinkers, alcohol consumption was associated with a linear, positive increase in mortality risk from all causes, cancer, and cerebrovascular disease in both men and women, but not heart disease in men. Taking of liver holidays was associated with a lower risk of cancer and cerebrovascular disease mortality in men.

CONCLUSIONS

Alcohol intake showed J-shaped associations with the risk of total mortality and three leading causes of death. However, heavy drinking increases the risk of mortality, which highlights the necessity of drinking in moderation coupled with liver holidays.