Sleep duration, its change, and risk of dementia among Japanese: The Japan Public Health Center-based Prospective Study

OBJECTIVE

Previous findings on the association between sleep duration, changes in sleep duration, and long-term dementia risk were mixed. Thus, we aimed to investigate the association between midlife sleep duration, its change, and dementia.

METHODS

We recruited 41,731 Japanese (40-71 years) and documented their habitual sleep duration at baseline (1990-1994) and a 5-year follow-up survey. Changes in sleep duration were calculated as differences between baseline and 5-year measurements. We identified dementia using the Long-Term Care Insurance system (2007-2016). Hazard ratios (HRs) and 95% confidence intervals (CIs) of dementia were calculated using the area-stratified Cox model.

RESULTS

During 360,389 person-years, 4621 participants exhibited dementia. The multivariable HRs of dementia compared with 7 h of sleep were 1.13 (95% CI: 0.98-1.30) for 3-5 h, 0.93 (0.85-1.02) for 6 h, 1.06 (0.99-1.14) for 8 h, 1.13 (1.01-1.27) for 9 h, and 1.40 (1.21-1.63) for 10-12 h with a J-shaped fashion (p for linear < 0.001 and quadratic < 0.001). For its change, the HRs compared with no change were 1.02 (0.90-1.16) for decreased ≥2 h, 0.95 (0.88-1.03) for decreased 1 h, 1.00 (0.91-1.09) for increased 1 h, and 1.37 (1.20-1.58) for increased ≥2 h. The positive association for decreased sleep duration was observed in individuals with an initial sleep duration of ≤7 h, but not in those with ≥8 h (p for interaction = 0.007).

CONCLUSIONS

Long and increased sleep duration was associated with a higher risk of dementia.

Dietary Macronutrient Intake and Cardiovascular Disease Risk and Mortality: A Systematic Review and Dose-Response Meta-Analysis of Prospective Cohort Studies

Many epidemiological studies have evaluated the intake of macronutrients and the risk of mortality and cardiovascular disease (CVD). However, current evidence is conflicting and warrants further investigation. Therefore, we carried out an umbrella review to examine and quantify the potential dose-response association of dietary macronutrient intake with CVD morbidity and mortality. Prospective cohort studies from PubMed, Embase, and CENTRAL were reviewed, which reported associations of macronutrients (protein, fat, and carbohydrate) with all-cause, CVD, cancer mortality, or CVD events. Multivariable relative risks (RR) were pooled, and heterogeneity was assessed. The results of 124 prospective cohort studies were included in the systematic review and 101 in the meta-analysis. During the follow-up period from 2.2 to 30 years, 506,086 deaths and 79,585 CVD events occurred among 5,107,821 participants. High total protein intake was associated with low CVD morbidity (RR 0.88, 95% confidence interval 0.82-0.94), while high total carbohydrate intake was associated with high CVD morbidity (1.08, 1.02-1.13). For fats, a high intake of total fat was associated with a decreased all-cause mortality risk (0.92, 0.85-0.99). Saturated fatty acid intake was only associated with cancer mortality (1.10, 1.06-1.14); Both monounsaturated fatty acid (MUFA) and polyunsaturated fatty acids (PUFA) intake was associated with all-cause mortality (MUFA: 0.92, 0.86-0.98; PUFA: 0.91, 0.86-0.96). This meta-analysis supports that protein intake is associated with a decreased risk of CVD morbidity, while carbohydrate intake is associated with an increased risk of CVD morbidity. High total fat intake is associated with a low risk of all-cause mortality, and this effect was different in an analysis stratified by the type of fat.

Body mass index, weight change in midlife, and dementia incidence: the Japan Public Health Center-based Prospective Study

INTRODUCTION

Insufficient evidence exists on the sex-specific associations of body mass index (BMI) and weight change through midlife with dementia incidence, especially in Asian populations.

METHODS

For 37,414 Japanese residents aged 40 to 59 years, BMIs at baseline (year 1990 or 1993) and 10-year follow-ups were obtained. Weight changes between baseline and 10-year follow-ups were determined. Disabling dementia incidence from 2006 to 2016 was ascertained using long-term care insurance (LTCI) certifications. Hazard ratios (HRs) were computed.

RESULTS

Increased dementia risk was observed with obesity at baseline and with underweight at 10-year follow-ups. Weight loss after baseline was at greater risk than weight gain. No sex difference was observed.

DISCUSSION

In both sexes, obesity in midlife increased the risk of developing dementia with increasing impacts of weight loss after midlife. A healthy body weight throughout adulthood is beneficial for dementia prevention.

Highlights

Obesity in midlife is a risk factor for incident dementia.Weight loss is a bigger risk factor than weight gain in later midlife.Association of BMI and weight change in midlife with dementia does not vary by sex.

Hobby Engagement and Risk of Disabling Dementia

BACKGROUND

The association between hobby engagement and risk of dementia reported from a short-term follow-up study for individuals aged ≥65 years may be susceptible to reverse causation. We examined the association between hobby engagement in age of 40-69 years and risk of dementia in a long-term follow-up study among Japanese, including individuals in mid-life, when the majority of individuals have normal cognitive function.

METHODS

A total of 22,377 individuals aged 40-69 years completed a self-administered questionnaire in 1993-1994. The participants answered whether they had hobbies according to the three following responses: having no hobbies, having a hobby, and having many hobbies. Follow-up for incident disabling dementia was conducted with long-term care insurance data from 2006 to 2016.

RESULTS

During a median of 11.0 years of follow-up, 3,095 participants developed disabling dementia. Adjusting for the demographic, behavioral, and psychosocial factors, the multivariable hazard ratios of incident disabling dementia compared with "having no hobbies" were 0.82 (95% confidence interval [CI], 0.75-0.89) for "having a hobby" and 0.78 (95% CI, 0.67-0.91) for "having many hobbies". The inverse association was similarly observed in both middle (40-64 years) and older ages (65-69 years). For disabling dementia subtypes, hobby engagement was inversely associated with the risk of dementia without a history of stroke (probably non-vascular type dementia), but not with that of post-stroke dementia (probably vascular type dementia).

CONCLUSION

Hobby engagement in both mid-life and late life was associated with a lower risk of disabling dementia without a history of stroke.

Dietary intake, biomarkers and supplementation of fatty acids and risk of coronary events: a systematic review and dose-response meta-analysis of randomized controlled trials and prospective observational studies

We aimed to review the association of dietary fats and risk of coronary events in adults. We searched PubMed, Embase, CENTRAL, Scopus, and Web of Sciences to April 2022 for prospective cohorts and randomized trials investigating the association of dietary intake and biomarkers of fats and fatty acid interventions and the risk of coronary events. We performed random-effects meta-analyses to estimate relative risk (RR) for the top versus bottom tertiles of exposures. One-hundered sixty-five prospective cohorts and randomized trials were included. Dietary intake and biomarkers of total fat and saturated, monounsaturated, and polyunsaturated fatty acids were not associated with the risk of coronary events. Dietary intake of trans fatty acids, palmitic acid, stearic acid, and saturated fatty acids from meat and unprocessed meat was modestly associated with a higher risk and, in contrast, intake of alpha-linolenic acid, long-chain omega-3 fatty acids, and linoleic acid was modestly associated with a lower risk. Supplementation with long-chain omega-3 fatty acids and increasing the consumption of alpha-linolenic and linoleic acids in place of saturated fats reduced the risk of coronary events. Existing evidence, in its totality, provides a modest support in favor of current recommendations suggesting replacement of saturated fats with polyunsaturated fats.

Bowel movement frequency, stool consistency, and risk of disabling dementia: a population-based cohort study in Japan

OBJECTIVES

This population-based study aimed to evaluate the association between bowel habits from midlife and dementia.

STUDY DESIGN

This was a cohort study using certification records for national long-term care insurance in Japan.

METHODS

Participants aged 50 to 79 years who reported bowel habits from eight districts within the Japan Public Health Center-based Prospective Study (JPHC Study) were followed from 2006 to 2016 for incident dementia. Hazard ratio (HR) and 95% confidence interval (CI) were estimated for men and women separately using Cox proportional hazards models accounting for various lifestyle factors and medical histories.

RESULTS

Among 19,396 men and 22,859 women, 1889 men and 2685 women were diagnosed with dementia. In men, the multivariable-adjusted HRs compared with bowel movement frequency (BMF) of once/day were 1.00 (95% CI: 0.87-1.14) for twice/day or more, 1.38 (1.16-1.65) for 5-6 times/week, 1.46 (1.18-1.80) for 3-4 times/week, and 1.79 (1.34-2.39) for <3 times/week (P for trend <0.001). In women, the corresponding HRs were 1.14 (0.998-1.31), 1.03 (0.91-1.17), 1.16 (1.01-1.33), and 1.29 (1.08-1.55) (P for trend = 0.043). Harder stool was associated with higher risk (P for trend: 0.0030 for men and 0.024 for women), with adjusted HRs compared to normal stool of 1.30 (1.08-1.57) for hard stool and 2.18 (1.23-3.85) for very hard stool in men, and 1.15 (1.002-1.32) and 1.84 (1.29-2.63) in women.

CONCLUSIONS

Lower BMF and harder stool were each associated with higher risk of dementia.

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

BACKGROUND

Some studies have investigated the relation between dairy products and mortality, but with inconsistent results.

OBJECTIVE

We examined the association between the consumption of dairy products and the risk of all-cause, cancer-related, and cardiovascular disease (CVD)-related mortality.

METHODS

From the Japan Public Health Center-based Prospective (JPHC) study, 43,117 males and 50,193 females with no history of cancer or CVD finished the food frequency questionnaire (FFQ) and were included in the study. Intake of dairy products was assessed using the FFQ and adjusted for total energy by using the residual method. We used multivariate Cox proportional hazard models to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for mortality risk in males and females.

RESULTS

14,211 deaths in males and 9547 deaths in females from all causes were identified during an average follow-up of 19.3 years. For males, total dairy consumption was nonlinearly and significantly associated with lower risk of mortality from all causes [the third quartile, HR = 0.87 (0.83, 0.91), the fourth quartile, HR = 0.89 (0.85, 0.94), P for nonlinearity < 0.001] and CVD [the third quartile, HR = 0.77 (0.70, 0.85), the fourth quartile, HR = 0.78 (0.70, 0.86), P for nonlinearity < 0.001]. Milk and fermented milk intake were inversely associated with all-cause and CVD-related mortality in males. Cheese consumption was inversely associated with CVD-related mortality among males. There was no association between total dairy intake and mortality risk among females.

CONCLUSION

For Japanese people, consumption of dairy products was associated with a decreased risk of mortality from all-cause and cardiovascular diseases among males.

Alcohol consumption from midlife and risk of disabling dementia in a large population-based cohort study in Japan

OBJECTIVES

The association between alcohol consumption and dementia in Japanese is poorly understood, and use of single-point alcohol assessment may cause measurement error. We explored this association in Japanese using repeated alcohol assessments.

METHODS

Participants in the Japan Public Health Center-based Prospective Study (JPHC Study) since 1990 and who were alive in 2006 were followed from 2006 until 2016 for dementia ascertainment. Disabling dementia was identified through long-term care insurance records. Alcohol consumption was assessed at the 5-year questionnaire survey (1995-1999) and drinking patterns were assessed on repeated follow-up (2000-2003). We performed Cox proportional hazards models with age as the time-scale with adjustment for various lifestyle factors and medical history using light consumption (<75 g ethanol/week, hereinafter "g") as reference. Analysis considering death as a competing risk was also conducted.

RESULTS

Among 42,870 participants aged 54-84 years, 4802 cases of disabling dementia were newly diagnosed. Average years from alcohol assessment until dementia incidence was 14.9 years. Non-drinkers and regular drinkers with ≥450 g at 5 years had adjusted HRs (95% CI) of 1.29 (1.12-1.47) and 1.34 (1.12-1.60). Patterns of long-term abstinence, former drinking, and regular heavy weekly consumption of ≥450 g showed increased adjusted HRs of 1.61 (1.28-2.03), 2.54 (1.93-3.35), and 1.96 (1.49-2.59), respectively. Competing risk analysis yielded similar results.

CONCLUSIONS

In Japanese, non-drinking and regular weekly consumption of ≥450 g from midlife were associated with high risk of disabling dementia compared with light drinking.

Association Between Fatty Acid Intakes and Age-Related Macular Degeneration in a Japanese Population: JPHC-NEXT Eye Study

Purpose

To determine the associations between fatty acid intakes and the prevalence of age-related macular degeneration (AMD) under a population-based cross-sectional study.

Methods

Residents of Chikusei City aged ≥40 years underwent systemic and eye screening. AMD was graded according to a modified version of the Age-Related Eye Disease Study classification. Dietary intake was assessed using a food frequency questionnaire and was adjusted for total energy intake.

Results

Altogether, 10,788 eyes of 5394 participants, 2116 men (mean [standard deviation (SD)] age, 62.4 [9.4] years) and 3278 women (60.6 [9.5] years), were included. The mean daily total fat intakes were 52.8 g and 59.0 g in men and women, respectively. After adjustments for potential confounders, saturated fatty acid (SFA) intake was inversely associated with the prevalence of any AMD in men (for each energy-adjusted 1-SD increase: odds ratio [OR], 0.86; 95% confidence interval [CI], 0.74-1.00). Significant trends were found for decreasing odds ratios of AMD with increasing SFA, monounsaturated fatty acid (MUFA), and polyunsaturated fatty acid (PUFA) intake (P for trend = 0.02, 0.04, and 0.04, respectively). In women, only a significant association was observed between the second quartile of linolenic acid intake and the prevalence of any AMD (OR, 0.78; 95% CI, 0.62-0.99).

Conclusions

We found an inverse association of SFA intake and a weak inverse association of MUFA and PUFA intakes with the prevalence of any AMD in a Japanese population.

Translational Relevance

Adequate fatty acid intake may be necessary to prevent or decelerate AMD.

Signaling pathways of chronic kidney diseases, implications for therapeutics

Chronic kidney disease (CKD) is a chronic renal dysfunction syndrome that is characterized by nephron loss, inflammation, myofibroblasts activation, and extracellular matrix (ECM) deposition. Lipotoxicity and oxidative stress are the driving force for the loss of nephron including tubules, glomerulus, and endothelium. NLRP3 inflammasome signaling, MAPK signaling, PI3K/Akt signaling, and RAAS signaling involves in lipotoxicity. The upregulated Nox expression and the decreased Nrf2 expression result in oxidative stress directly. The injured renal resident cells release proinflammatory cytokines and chemokines to recruit immune cells such as macrophages from bone marrow. NF-κB signaling, NLRP3 inflammasome signaling, JAK-STAT signaling, Toll-like receptor signaling, and cGAS-STING signaling are major signaling pathways that mediate inflammation in inflammatory cells including immune cells and injured renal resident cells. The inflammatory cells produce and secret a great number of profibrotic cytokines such as TGF-β1, Wnt ligands, and angiotensin II. TGF-β signaling, Wnt signaling, RAAS signaling, and Notch signaling evoke the activation of myofibroblasts and promote the generation of ECM. The potential therapies targeted to these signaling pathways are also introduced here. In this review, we update the key signaling pathways of lipotoxicity, oxidative stress, inflammation, and myofibroblasts activation in kidneys with chronic injury, and the targeted drugs based on the latest studies. Unifying these pathways and the targeted therapies will be instrumental to advance further basic and clinical investigation in CKD.

Cardiovascular disease, a major global burden: Epidemiology of stroke and ischemic heart disease in Japan

Japan ranks the highest globally, in terms of longevity. The average life expectancy was 81.4 years for men and 87.5 years for women in 2019. Such success in health is attributable to the substantial reduction in age-standardized mortality from cardiovascular diseases, especially stroke (136 per 10⁵ in 1980 and 24 per 10⁵ in 2015), when stroke mortality was the highest in the world between the 1960s and the 1990s. On the other hand, ischemic heart disease mortality was the lowest in the world between the 1960s and the 1980s and has continued to decline (40 per 10⁵ in 1980 and 17 per 10⁵ in 2015). Such a disease profile (larger burden of stroke compared to ischemic heart disease) was observed not only in Japan but also in some countries in central Asia and Africa, where small vessel disease (arteriolosclerosis) is assumed to be more common than large vessel disease (atherosclerosis). Between 1970 and 2015, a large decline in the population with high blood pressure levels was observed for both men and women. Meanwhile, there was a moderate decline in the smoking rate among men, and an increasing trend in serum cholesterol levels in both men and women. The sharp and extensive socioeconomic development between the 1960s and 1990s contributed to these health outcomes, while preventive measures and improved emergency medical care also contributed to the reduction of risk factors, disease incidence, case-fatality, and mortality. However, there is a threat of increasing incidence of ischemic heart disease in urban male employees and middle-aged male residents. Japan, with a super-aging society, needs to develop a new model for the prevention and control of cardiovascular disease and related health issues, with emphasis on efforts towards the early (primordial) prevention of cardiovascular disease as well as the attenuation of their progress towards chronic heart failure, chronic kidney disease, and vascular dementia.

Association of serum levels of antibodies against ALDOA and FH4 with transient ischemic attack and cerebral infarction

Background

Ischemic stroke, including transient ischemic attack (TIA) and acute-phase cerebral infarction (aCI), is a serious health problem in the aging society. Thus, this study aimed to identify TIA and aCI biomarkers.

Methods

In 19 patients with TIA, candidate antigens recognized by serum IgG autoantibodies were screened using a human aortic endothelial cell cDNA library. Through amplified luminescent proximity homogeneous assay-linked immunosorbent assay (AlphaLISA), serum antibody levels against the candidate antigens were examined in healthy donor (HD), TIA, and aCI cohorts (n = 285, 92, and 529). The plasma antibody levels in the Japan Public Health Center-based Prospective Cohort Study (1991–1993) were also examined.

Results

The candidate antigens were aldolase A (ALDOA) and fumarate hydratase (FH). In AlphaLISA, patients with TIA or aCI had higher anti-ALDOA antibody (ALDOA-Ab) and anti-FH antibody (FH-Ab) levels than the HDs (P < 0.05). In a multivariate logistic regression analysis, the ALDOA-Ab (odds ratio [OR]: 2.46, P = 0.0050) and FH-Ab (OR: 2.49, P = 0.0037) levels were independent predictors of TIA. According to the case–control study, the ALDOA-Ab (OR: 2.50, P < 0.01) and FH-Ab (OR: 2.60, P < 0.01) levels were associated with aCI risk. In a correlation analysis, both ALDOA-Abs and FH-Abs were well associated with hypertension, coronary heart disease, and habitual smoking. These antibody levels also correlated well with maximum intima–media thickness, which reflects atherosclerotic stenosis.

Conclusions

ALDOA-Abs and FH-Abs can be novel potential biomarkers for predicting atherosclerotic TIA and aCI.

Nutritional Viewpoints on Eggs and Cholesterol

Although most current epidemiologic studies indicate no significant association between consuming one egg daily and blood cholesterol levels and cardiovascular risk, arguments still persist with a positive association. Since the diet is one of the most influential factors for this association, we illustrate characteristic features in Japanese people whose dietary pattern is distinct from that, for example, the US (United States) population. Available epidemiologic studies in healthy Japanese people show no association between consumption of one egg daily and blood cholesterol level, consistent with those observed in the US population. However, when consumption of major nutrients and food sources of cholesterol are compared to the US population, Japanese people may have an extra-reserve against the influence of eggs on cardiovascular risk markers, despite consuming relatively more eggs. Further discussion on the influence of nutrients contained in the egg and dietary pattern, including interaction with gut microbes, is necessary. In addition, special consideration at the personalized level is needed for judgment regarding dietary cholesterol not only for hypercholesterolemic patients but for hyper-responsive healthy persons. Although randomized controlled trials with long-term follow-up are required to evaluate the association between consumption of eggs and human health, available information, at least from the nutritional viewpoint, suggests that egg is a healthy and cost-efficient food worldwide.

Lower intake of saturated fatty acids is associated with persistently higher arterial stiffness in patients with type 2 diabetes

AIMS/INTRODUCTION

There are few studies to investigate the relationship between macronutrients and longitudinal changes in arterial stiffness in patients with type 2 diabetes mellitus. This exploratory study sought to determine whether macronutrients were correlated with increased arterial stiffness independently of conventional atherosclerotic risk factors.

MATERIALS AND METHODS

The study participants comprised 733 type 2 diabetes outpatients who had no apparent history of cardiovascular diseases. The dietary schedule was assessed with a validated, brief, self-administered diet history questionnaire. At baseline and at years 2 and 5, brachial-ankle pulse wave velocity was measured. A multivariable linear mixed-effects model was used to determine the predictive values of macronutrients and atherosclerotic risk factors for longitudinal changes in brachial-ankle pulse wave velocity.

RESULTS

There was a significant increase in brachial-ankle pulse wave velocity values over the 5-year follow-up period. In a multivariable linear mixed-effects model that adjusted for age and sex, lower saturated fatty acid intake was significantly correlated with persistently higher brachial-ankle pulse wave velocity, independently of other atherosclerotic risk factors. Lower intake of dairy products in particular showed this correlation.

CONCLUSIONS

Our data showed that lower saturated fatty acids intake was correlated with persistently higher brachial-ankle pulse wave velocity in type 2 diabetes patients. Among food sources of saturated fatty acids, lower dairy products specifically were correlated with elevated brachial-ankle pulse wave velocity. This might be because the consumption of dairy products in Japan is much lower than in Western countries.

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 of Serum Fatty Acids at Admission with the Age of Onset of Intracerebral Hemorrhage

Dietary triglycerides influence the serum concentrations of fatty acids (FA) and their weight percentages (wt%), which might be associated with the age of onset of intracerebral hemorrhage (ICH). We investigated the correlation between serum FA levels and proportions at admission, and the age at onset of ICH. We included patients admitted between 2016 and 2019 within 24 h of the onset of ICH, and calculated the correlation coefficients between their age, serum FA concentration, and FA wt%. We performed multiple linear regression analysis to identify individual FAs related to the age at onset of ICH. Furthermore, we estimated the threshold values of FAs that were independently associated with the age at onset of ICH <65 years, using receiver operating characteristic curves by logistic regression. Our inclusion criteria were met by 141 patients (mean age, 67 years). The concentration of dihomo-gamma-linolenic acid (DGLA) and the wt% of eicosapentaenoic acid (EPA) were significant independent variables for the age at onset of ICH. The ROC curves for the age of onset <65 years were ≥108.6 µmol/L for DGLA and ≤1.7% for EPA. Increased DGLA concentration and decreased EPA wt% were significantly associated with young-onset ICH.

Why has Japan become the world's most long-lived country: insights from a food and nutrition perspective

In an international comparison of recent mortality statistics among G7 countries, Japan had the longest average life expectancy, primarily due to remarkably low mortality rates from ischemic heart disease and cancer (particularly breast and prostate). As recently as the 1960s, life expectancy in Japan was the shortest among the G7 countries, owing to relatively high mortality from cerebrovascular disease—particularly intracerebral hemorrhage—and stomach cancer. Mortality rates for these diseases subsequently decreased significantly while the already low rates for ischemic heart disease and cancer also decreased, resulting in Japanese life expectancy becoming the longest. The low mortality rates from ischemic heart disease and cancer are thought to reflect the low prevalence of obesity in Japan; low intake of red meat, specifically saturated fatty acids; and high intakes of fish, specifically n-3 polyunsaturated fatty acids, plant foods such as soybeans, and nonsugar-sweetened beverages such as green tea. The decreasing mortality rates from cerebrovascular disease are thought to reflect the increases in animal foods, milk, and dairy products and consequently in saturated fatty acids and calcium, together with a decrease in salt intake which may have led to a decrease in blood pressure. This decrease in salt and highly salted foods also seems to account for the decrease in stomach cancer. The typical Japanese diet as characterized by plant food and fish as well as modest Westernized diet such as meat, milk and dairy products might be associated with longevity in Japan.

Frequency of Seaweed Intake and Its Association with Cardiovascular Disease Mortality: The JACC Study

AIM

Seaweed is a popular traditional foodstuff in Asian countries. To our knowledge, few studies have examined the association of seaweed intake with mortality from cardiovascular disease. We examined the association of frequency of seaweed intake with total and specific cardiovascular disease mortality.

METHODS

We examined the association of seaweed intake with mortality from cardiovascular disease among 40,234 men and 55,981 women who participated in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk. Sex-specific hazard ratios for mortality from cardiovascular disease (stroke, stroke subtypes, and coronary heart disease) according to the frequency of seaweed intake were calculated stratified by study area and adjusted for potential cardiovascular risk factors and dietary factors.

RESULTS

During the 1,580,996 person-year follow-up, 6,525 cardiovascular deaths occurred, of which 2,820 were due to stroke, and 1,378, to coronary heart disease. Among men, the multivariable analysis showed that participants who ate seaweed almost every day compared with those who never ate seaweed had hazard ratios (95% confidence interval; P for trend) of 0.79 (0.62-1.01; 0.72) for total cardiovascular disease, 0.70 (0.49-0.99; 0.47) for total stroke, 0.69 (0.41-1.16; 0.11) for cerebral infarction. Among women, the multivariable-adjusted hazard ratios were 0.72 (0.55-0.95; 0.001) for total cardiovascular disease, 0.70 (0.46-1.06; 0.01) for total stroke, and 0.49 (0.27-0.90; 0.22) for cerebral infarction. No associations were observed between seaweed intake and risk of intraparenchymal hemorrhage and coronary heart disease among either men or women.

CONCLUSIONS

We found an inverse association between seaweed intake and cardiovascular mortality among Japanese men and women, especially that from cerebral infarction.

Dietary saturated fat intake and risk of stroke: Systematic review and dose-response meta-analysis of prospective cohort studies

BACKGROUND AND AIMS

Because of the conflicting research results, the association between saturated fatty acid (SFA) consumption and the risk of stroke remains controversial. We conducted a meta-analysis to evaluate potential dose-response relation between SFA intake and stroke.

METHODS AND RESULTS

PubMed, Embase, the Cochrane Library Central Register of Controlled Trials, and Web of Science were searched. Summary relative risks (RRs) of the highest vs. the lowest category of SFA intake and their 95% confidence intervals (CIs) were pooled by random-effects models. Linear or nonlinear dose-response trend estimations were evaluated with data from categories of SFA consumption in each study. Fourteen studies involving a total of 598,435 participants were eligible for high vs. low meta-analysis, and 12 studies involving a total of 462,268 participants were eligible for the dose-response relation assessment. Higher dietary SFA intake was associated with a decreased overall risk for stroke (RR, 0.87; 95% CI, 0.78-0.96; I² = 37.8%). A linear relation between SFA and stroke was explored (P = 0.01), the pooled RR of stroke per 10 g/day increase in SFA intake was 0.94 (95% CI, 0.89-0.98; P = 0.01).

CONCLUSION

This meta-analysis further demonstrated that a higher consumption of dietary SFA is associated with a lower risk of stroke, and every 10 g/day increase in SFA intake is associated with a 6% relative risk reduction in the rate of stroke. Further research is needed to explore the influence of specific SFA types and different macronutrient replacement models of SFA on the stroke risk.

SCD rs41290540 single-nucleotide polymorphism modifies miR-498 binding and is associated with a decreased risk of coronary artery disease

Background

Atherosclerosis is the primary cause of coronary artery disease (CAD), and stearoyl‐CoA desaturase (SCD) is associated with atherosclerosis. However, the associations between variants of SCD and CAD have not yet been decided.

Methods

This study analyzed SCD rs41290540 single‐nucleotide polymorphism (SNP) in the 3′‐untranslated region for an association with a risk of CAD among the Chinese Han population. CAD patients and controls were genotyped for SNP rs41290540 in SCD by SNaPshot. The binding affinity of miR‐498 to rs41290540 was determined by a luciferase assay, and SCD expression was assessed using Western blot.

Results

A total of 969 CAD patients and 1,095 control subjects were involved in this study. The SCD rs41290540CC genotype is associated with a decreased risk of CAD compared with the AA genotype. Furthermore, the CC genotype is associated with lower serum total cholesterol (TC). Western blot analysis demonstrated that miR‐498 suppressed the expression of SCD. A luciferase assay confirmed that rs41290540 A>C variation in the SCD 3′UTR inhibits miR‐498 binding.

Conclusion

This study demonstrates that the SCD rs41290540 may be associated with a decreased risk of CAD, lower serum TC, and decreased miR‐498 binding.

Plasma Phospholipid Fatty Acids, FADS1 and Risk of 15 Cardiovascular Diseases: A Mendelian Randomisation Study

Whether circulating fatty acids (FAs) play a causal role in the development of cardiovascular disease (CVD) remains unclear. We conducted a Mendelian randomisation study to explore the associations between plasma phospholipid FA levels and 15 CVDs. Summary-level data from the CARDIoGRAMplusC4D, MEGASTROKE, and Atrial Fibrillation consortia and UK Biobank were used. Sixteen single-nucleotide polymorphisms (SNPs) associated with ten plasma FAs were used as instrumental variables. SNPs in or close to the FADS1 gene were associated with most FAs. We performed a secondary analysis of the association between a functional variant (rs174547) in FADS1, which encodes ?5-desaturase (a key enzyme in the endogenous FA synthesis), and CVD. Genetic predisposition to higher plasma α-linolenic, linoleic, and oleic acid levels was associated with lower odds of large-artery stroke and venous thromboembolism, whereas higher arachidonic and stearic acid levels were associated with higher odds of these two CVDs. The associations were driven by SNPs in or close to FADS1. In the secondary analysis, the minor allele of rs174547 in FADS1 was associated with significantly lower odds of any ischemic stroke, large-artery stroke, and venous thromboembolism and showed suggestive evidence of inverse association with coronary artery disease, abdominal aortic aneurysm and aortic valve stenosis. Genetically higher plasma α-linolenic, linoleic, and oleic acid levels are inversely associated with large-artery stroke and venous thromboembolism, whereas arachidonic and stearic acid levels are positively associated with these CVDs. The associations were driven by FADS1, which was also associated with other CVDs.

Non-High-Density Lipoprotein Cholesterol and Risk of Stroke Subtypes and Coronary Heart Disease: The Japan Public Health Center-Based Prospective (JPHC) Study

Aim: A positive association between non-high-density lipoprotein cholesterol (non-HDL-C) and coronary heart disease (CHD) has been established; however, associations between non-HDL-C and stroke subtypes have not been determined.

Methods: We conducted a prospective study of 30,554 individuals aged 40–69 yrs with no history of cardiovascular disease (CVD) in Japan. Sex-specific hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of stroke subtypes and CHD were estimated according to quintiles of non-HDL-C, using Cox proportional hazard models adjusted for other established risk factors.

Results: We identified 1,705 stroke and 296 CHD events over a median 15 yrs of follow-up. The fractional polynomials analysis revealed a U-shaped association between non-HDL-C and stroke risk in men. When analyzed for stroke subtypes, the data revealed an inverse relationship between non-HDL-C and intracerebral hemorrhage (ICH), primarily with lobar ICH, and a positive association between non-HDL-C and large-artery occlusive infarction in men [adjusted HR 0.55 (95% CI, 0.35–0.87) and 2.05 (95% CI, 1.07–3.93) for the highest and lowest quintile of non-HDL-C, respectively]. The lowest risk of ICH in women was observed in the fourth quintile, and the lowest risk of embolic infarction was observed in the third quintile. In contrast, non-HDL-C was positively associated with CHD in both sexes.

Conclusions: In Japanese men, lower non-HDL-C levels were associated with a decreased risk of large-artery occlusive infarction and an increased risk of ICH, particularly lobar ICH.

Overall nutrient and total fat intake among Japanese people: The INTERLIPID Study Japan

BACKGROUND AND OBJECTIVES

Total fat intake is linked to the intake of other nutrients. Little data are available on the extent to which total fat affects diet quality in Japanese people. We investigated the relationship between total fat intake and other nutrient intake using INTERLIPID/ INTERMAP data on Japanese people living in Japan.

METHODS AND STUDY DESIGN

The participants included 371 men and 401 women with a healthy body mass index and between the ages of 40 and 59 from 4 population samples in Japan. Nutrient intake data were based on four in-depth 24-hour dietary recalls per person.

RESULTS

Analysis of covariance adjusted for age revealed that total fat intake was positively related to intakes of calcium, thiamine, riboflavin, meat, eggs, and milks and dairy products for both sexes. Total fat intake was inversely associated with carbohydrate and cereals intake for both sexes. On average, men with total fat intake between 25.0 and 27.4% of total energy had saturated fatty acids above 7%, which is the upper limit recommended for preventing lifestyle-related diseases. Men with total fat intake less than 20% of total energy had a higher risk of not meeting the Dietary Reference Intakes for Japanese (2015) for some nutrients.

CONCLUSIONS

Total fat intake was positively associated with calcium, thiamine, and riboflavin intakes and inversely associated with carbohydrate intake. Our results suggest that in 40-59-year-old men with a healthy body mass index, total fat intake between 20 and 27% of total energy may best support adequate intake of other nutrients.

A Low ω-6/ω-3 Ratio High-Fat Diet Improves Rat Metabolism via Purine and Tryptophan Metabolism in the Intestinal Tract, While Reversed by Inulin

A high-fat diet (HFD) is the main cause of metabolic diseases. However, HFD in previous studies consists of much lard, which contains a large amount of omega-6 (ω-6) polyunsaturated fatty acid (PUFA) and little omega-3 (ω-3) PUFA. The role of ω-6/ω-3 ratio of HFD in the development of metabolic diseases remains incompletely discussed. In this study, rats were fed with either a low or a high ω-6/ω-3 ratio HFD singly or combined with inulin. Metabolism state was valued and metabolomics of cecal content were detected. Results show that HFD with low ω-6/ω-3 ratio promotes the glucose utilization in rats. However, inulin had different effects on metabolism with different diets. Xanthosine and kynurenic acid in cecum were positively related to epididymal white adipose tissues (eWAT) mass. The present study indicates the beneficial effects of low ω-6/ω-3 ratio HFD (LRD) on the metabolic state of rats. Moreover, xanthosine and kynurenic acid were closely related to the development of metabolic diseases.

Dietary total fat, fatty acids intake, and risk of cardiovascular disease: a dose-response meta-analysis of cohort studies

Background

Several epidemiological studies have investigated the association between dietary fat intake and cardiovascular disease. However, dietary recommendations based on systematic review and meta-analysis might be more credible.

Methods and results

Pubmed, Embase and Cochrane library were searched up to July 1st 2018 for cohort studies reporting associations of dietary fat intake and risk of CVDs. By comparing the highest vs. the lowest categories of fat or fatty acids intake, we found that higher dietary trans fatty acids (TFA) intake was associated with increased risk of CVDs [RR:1.14(1.08–1.21)]. However, no association was observed between total fat, monounsaturated fatty acids (MUFA), saturated fatty acids (SFA), and polyunsaturated fatty acids (PUFA), and risk of CVDs. Subgroup analysis found a cardio-protective effect of PUFA in the studies that has been followed up more than 10 years [0.95(0.91–0.99), I² = 62.4%]. Dose-response analysis suggested that the risk of CVDs increased 16% [1.16 (1.07–1.25), P_linearity = 0.033] for an increment of 2% energy/day of TFA intake.

Conclusions

This current meta-analysis of cohort studies suggested that total fat, SFA, MUFA, and PUFA intake were not associated with the risk of cardiovascular disease. However, we found that higher TFA intake is associated with greater risk of CVDs in a dose-response fashion. Furthermore, the subgroup analysis found a cardio-protective effect of PUFA in studies followed up for more than 10 years.

Electronic supplementary material

The online version of this article (10.1186/s12944-019-1035-2) contains supplementary material, which is available to authorized users.

Dietary Intake of Energy and Nutrients from Breakfast and Risk of Stroke in The Japanese Population: The Circulatory Risk in Communities Study (CIRCS)

Aims: The frequency of breakfast intake has been reported to be inversely associated with the risk of cardiovascular events; however, it is uncertain what the impact of the energy and nutrient intakes from breakfast are. We assessed the association between these intakes from breakfast and the risk of stroke prospectively.

Methods: In a baseline survey of four Japanese communities between 1981 and 1990, we enrolled 3 248 residents (1 662 men and 1 586 women) aged 40–59 years who were free from stroke and heart disease and who responded to the 24-hour dietary recall survey. We assessed the dietary intake at breakfast, lunch, dinner, and other times separately.

Results: During the median 25-year follow-up, 230 individuals (147 men and 83 women) developed stroke. After adjustment for age, community, other dietary intakes, and lifestyle and physiological factors, the multivariable-adjusted hazard ratios (95% confidence intervals) of intracerebral hemorrhage for the highest versus lowest quartiles of energy intake from breakfast were 0.38 (0.15–0.99) in men and 1.36 (0.36–5.10) in women. For the major nutrients, a higher saturated or monounsaturated fat intake at breakfast was associated with a reduced risk of intracerebral hemorrhage in men, and remained statistically significant after further adjustment for intake of other major nutrients from breakfast.

Conclusions: A higher intake of energy from breakfast, primarily saturated or monounsaturated fat, was associated with a reduced risk of intracerebral hemorrhage in Japanese men.

Serial measures of circulating biomarkers of dairy fat and total and cause-specific mortality in older adults: the Cardiovascular Health Study

Background

Controversy has emerged about the benefits compared with harms of dairy fat, including concerns over long-term effects. Previous observational studies have assessed self-reported estimates of consumption or a single biomarker measure at baseline, which may lead to suboptimal estimation of true risk.

Objective

The aim of this study was to investigate prospective associations of serial measures of plasma phospholipid fatty acids pentadecanoic (15:0), heptadecanoic (17:0), and trans-palmitoleic (trans-16:1n-7) acids with total mortality, cause-specific mortality, and cardiovascular disease (CVD) risk among older adults.

Design

Among 2907 US adults aged ≥65 y and free of CVD at baseline, circulating fatty acid concentrations were measured serially at baseline, 6 y, and 13 y. Deaths and CVD events were assessed and adjudicated centrally. Prospective associations were assessed by multivariate-adjusted Cox models incorporating time-dependent exposures and covariates.

Results

During 22 y of follow-up, 2428 deaths occurred, including 833 from CVD, 1595 from non-CVD causes, and 1301 incident CVD events. In multivariable models, circulating pentadecanoic, heptadecanoic, and trans-palmitoleic acids were not significantly associated with total mortality, with extreme-quintile HRs of 1.05 for pentadecanoic (95% CI: 0.91, 1.22), 1.07 for heptadecanoic (95% CI: 0.93, 1.23), and 1.05 for trans-palmitoleic (95% CI: 0.91, 1.20) acids. Circulating heptadecanoic acid was associated with lower CVD mortality (extreme-quintile HR: 0.77; 95% CI: 0.61, 0.98), especially stroke mortality, with a 42% lower risk when comparing extreme quintiles of heptadecanoic acid concentrations (HR: 0.58; 95% CI: 0.35, 0.97). In contrast, heptadecanoic acid was associated with a higher risk of non-CVD mortality (HR: 1.27; 95% CI: 1.07, 1.52), which was not clearly related to any single subtype of non-CVD death. No significant associations of pentadecanoic, heptadecanoic, or trans-palmitoleic acids were seen for total incident CVD, coronary heart disease, or stroke.

Conclusions

Long-term exposure to circulating phospholipid pentadecanoic, heptadecanoic, or trans-palmitoleic acids was not significantly associated with total mortality or incident CVD among older adults. High circulating heptadecanoic acid was inversely associated with CVD and stroke mortality and potentially associated with higher risk of non-CVD death.

High Dietary Saturated Fat is Associated with a Low Risk of Intracerebral Hemorrhage and Ischemic Stroke in Japanese but not in Non-Japanese: A Review and Meta-Analysis of Prospective Cohort Studies

AIM

The associations between dietary saturated fatty acids and the risks of stroke subtypes in cohort studies were examined by a meta-analysis of separate ethnic Japanese and non-Japanese cohorts, and causes of their difference were elucidated.

METHOD

Log hazard ratio (HR) with 95% confidence interval (CI) of the highest versus the lowest saturated fat intake from cohort studies were weighed by an inverse variance method to combine HRs.

RESULTS

Five studies of intracerebral hemorrhage and 11 studies/comparisons of ischemic stroke were selected. A meta-analysis of intracerebral hemorrhage excluding subarachnoid hemorrhage showed a strong inverse association in Japanese (n=3, HR=0.55, 95% CI 0.32-0.94) but not in non-Japanese (n=2, HR=0.98, 95% CI 0.62-1.53). A meta-analysis of ischemic stroke showed a mild inverse association in Japanese (n=4, HR=0.82, 95% CI 0.71-0.93) but not in non-Japanese (n=7, HR= 0.93, 95% CI 0.84-1.03). The effect size of saturated fat in reducing the risk of stroke in Japanese was stronger for intracerebral hemorrhage (45% reduction) than for ischemic stroke (18% reduction).

CONCLUSIONS

In Japanese but not in non-Japanese, a diet high in saturated fat is associated with a low risk of intracerebral hemorrhage and ischemic stroke. This may be due to differences in the range of intake of saturated fat, genetic susceptibility, incidence of lacunar infarction, and/or confounding factors such as dietary proteins. An intervention study targeting Japanese will be required to verify the causality.

Associations of fats and carbohydrate intake with cardiovascular disease and mortality in 18 countries from five continents (PURE): a prospective cohort study

BACKGROUND

The relationship between macronutrients and cardiovascular disease and mortality is controversial. Most available data are from European and North American populations where nutrition excess is more likely, so their applicability to other populations is unclear.

METHODS

The Prospective Urban Rural Epidemiology (PURE) study is a large, epidemiological cohort study of individuals aged 35-70 years (enrolled between Jan 1, 2003, and March 31, 2013) in 18 countries with a median follow-up of 7·4 years (IQR 5·3-9·3). Dietary intake of 135 335 individuals was recorded using validated food frequency questionnaires. The primary outcomes were total mortality and major cardiovascular events (fatal cardiovascular disease, non-fatal myocardial infarction, stroke, and heart failure). Secondary outcomes were all myocardial infarctions, stroke, cardiovascular disease mortality, and non-cardiovascular disease mortality. Participants were categorised into quintiles of nutrient intake (carbohydrate, fats, and protein) based on percentage of energy provided by nutrients. We assessed the associations between consumption of carbohydrate, total fat, and each type of fat with cardiovascular disease and total mortality. We calculated hazard ratios (HRs) using a multivariable Cox frailty model with random intercepts to account for centre clustering.

FINDINGS

During follow-up, we documented 5796 deaths and 4784 major cardiovascular disease events. Higher carbohydrate intake was associated with an increased risk of total mortality (highest [quintile 5] vs lowest quintile [quintile 1] category, HR 1·28 [95% CI 1·12-1·46], p_trend=0·0001) but not with the risk of cardiovascular disease or cardiovascular disease mortality. Intake of total fat and each type of fat was associated with lower risk of total mortality (quintile 5 vs quintile 1, total fat: HR 0·77 [95% CI 0·67-0·87], p_trend<0·0001; saturated fat, HR 0·86 [0·76-0·99], p_trend=0·0088; monounsaturated fat: HR 0·81 [0·71-0·92], p_trend<0·0001; and polyunsaturated fat: HR 0·80 [0·71-0·89], p_trend<0·0001). Higher saturated fat intake was associated with lower risk of stroke (quintile 5 vs quintile 1, HR 0·79 [95% CI 0·64-0·98], p_trend=0·0498). Total fat and saturated and unsaturated fats were not significantly associated with risk of myocardial infarction or cardiovascular disease mortality.

INTERPRETATION

High carbohydrate intake was associated with higher risk of total mortality, whereas total fat and individual types of fat were related to lower total mortality. Total fat and types of fat were not associated with cardiovascular disease, myocardial infarction, or cardiovascular disease mortality, whereas saturated fat had an inverse association with stroke. Global dietary guidelines should be reconsidered in light of these findings.

FUNDING

Full funding sources listed at the end of the paper (see Acknowledgments).

SFA intake among Japanese schoolchildren: current status and possible intervention to prevent excess intake

Objective

Although a high intake of fat, particularly SFA, is a well-known risk factor for CVD, fat intake in Japan has attracted relatively little attention from health professionals to date due to the low intake in the Japanese population. However, recent surveys have shown an increase in fat intake in younger Japanese populations. Here, we described the fat intake and dietary sources of SFA in Japanese schoolchildren. Also, we experimentally exchanged a high-SFA food with a low-SFA substitute in the data, and calculated the resulting changes in nutrient intakes.

Design

The study was conducted nationwide under a cross-sectional design. A non-consecutive, three-day diet record was performed on two school days and a non-school day.

Setting

Fourteen elementary and thirteen junior high schools.

Subjects

Elementary-school children (n 629) and junior high-school children (n 281).

Results

Prevalence of excess fat intake was 35·4 % in boys and 45·0 % in girls. Excess SFA intake was suspected in 97·7 % of boys and 99·4 % of girls when the dietary reference intake values for adults were applied. Major dietary sources of SFA were meat (26·4 % of total SFA intake), dairy products (25·7 %) and confectioneries (11·3 %).

Conclusions

Since one-third to nearly one-half of our Japanese schoolchildren consumed excess fat, careful monitoring of fat intake in the Japanese population should be continued. Adoption of low-fat milk and/or lean meat in daily meals might be a suitable means of reducing fat, particularly SFA intake, in schoolchildren.

Association of high-density lipoprotein cholesterol concentration with different types of stroke and coronary heart disease: The Japan Public Health Center-based prospective (JPHC) study

BACKGROUND AND AIMS

Although low high-density lipoprotein (HDL) cholesterol concentration is an established risk factor for coronary heart disease (CHD), information regarding subtypes of stroke is very limited, especially in Asian populations.

METHODS

A prospective study was conducted among 30,736 individuals aged 40-69 years, who lived in nine communities in Japan and did not have a history of cardiovascular disease (CVD). CHD and stroke, including its subtypes, were assessed, and sex-specific hazard ratios (HRs) and 95% confidence intervals (CIs) for outcomes were estimated according to quintiles of HDL cholesterol using Cox proportional models adjusted for other CVD risk factors.

RESULTS

We identified 296 CHD and 1712 stroke events over a median 15 yr of follow-up. HDL cholesterol concentration showed an inverse association with CHD in men and women. A low HDL cholesterol concentration slightly raised the risk for total strokes in men, but not in women. When analyzed by subtypes, we observed an inverse relationship between HDL cholesterol concentration and the incidence of lacunar infarction, with an adjusted HR for the lowest quintile of HDL cholesterol concentration compared with the highest quintile of 1.63 (95% CI, 1.00-2.66) in men and 1.97 (95% CI, 1.19-3.26) in women. HDL cholesterol concentration was positively associated with the risk of intracerebral hemorrhage (ICH) in a linear manner in women (p for trend = 0.028), but not in men.

CONCLUSIONS

The associations of HDL cholesterol concentration with lacunar infarction and ICH may be related to different functional properties of HDL rather than to its protective function against lipid-rich atherosclerosis.

Quality of diet plans for weight loss featured in women's magazines. A cross-sectional descriptive study

CONTEXT AND OBJECTIVE:

Brazil has the fifth largest population of obese individuals in the world. Women's magazines publish a large number of diet plans, and therefore the objective of this study was to assess the quality of these plans.

DESIGN:

Cross-sectional descriptive study.

METHODS:

We included the Brazilian women's magazines of highest circulation published between January and June 2014 that advertised diets for weight loss on their covers. We extracted the quantities of macro and micronutrients from each of these diet plans and compared these quantities with the World Health Organization nutritional guidelines for adult women. We also checked the total energy quantities of these plans, and any recommendations about water intake and physical activity.

RESULTS:

We identified 136 potentially eligible magazine issues; 41 were excluded and 95 issues of 6 different magazines were included in the study. We found that 83.1 % of the plans had carbohydrate and fiber levels below the recommendations. On the other hand, the protein and saturated fatty acid levels were above the recommendations in 97.8% and 95.7% of the plans, respectively; 75.7% of the diets had inadequate calcium levels and 70.5% had low iron levels. Only 30 plans specified the total daily quantity of dietary energy and in 53.3% of these, the information was inconsistent with our estimates; 20% of the plans had no recommendations on daily water intake and 37.5% did not give recommendations regarding physical activity practices.

CONCLUSION:

The diet plans for weight loss featured in Brazilian women's magazines are of low quality.

Dietary patterns and all-cause, cancer, and cardiovascular disease mortality in Japanese men and women: The Japan public health center-based prospective study

OBJECTIVE

A meta-analysis showed an inverse association of a prudent/healthy dietary pattern with all-cause mortality and no association of a western/unhealthy dietary pattern. However, the association of distinctive dietary patterns of Japanese population with mortality remains unclear. We prospectively investigated the association between dietary patterns and all-cause, cancer, and cardiovascular disease mortality among Japanese adults.

METHODS

Participants were 36,737 men and 44,983 women aged 45-74 years who participated in the second survey of the Japan Public Health Center-based Prospective Study (1995-1998) and who had no history of serious disease. Dietary patterns were derived from principal component analysis of the consumption of 134 food and beverage items ascertained by a food frequency questionnaire. Hazard ratios of death from the second survey to December 2012 were estimated using cox proportional hazard regression analysis.

RESULTS

A prudent dietary pattern, which was characterized by high intake of vegetables, fruit, soy products, potatoes, seaweed, mushrooms, and fish, was significantly associated with decreased risk of all-cause and cardiovascular disease mortality. The multivariable-adjusted hazard ratios (95% confidence intervals) of all-cause and cardiovascular disease mortality for the highest versus lowest quartile of the prudent dietary pattern score were 0.82 (0.77 to 0.86) and 0.72 (0.64 to 0.79), respectively (P for trend <0.001 in both). A Westernized dietary pattern, characterized by high intake of meat, processed meat, bread, and dairy products, was also inversely associated with risk of all-cause, cancer, and cardiovascular disease mortality. A traditional Japanese dietary pattern was not associated with these risks.

CONCLUSIONS

The prudent and Westernized dietary patterns were associated with a decreased risk of all-cause and cardiovascular disease mortality in Japanese adults.

Dietary carbohydrate and fat intakes are differentially associated with lipid abnormalities in Korean adults

BACKGROUND

A high prevalence of metabolic syndrome along with increasing rates of low high-density lipoprotein cholesterol (HDL-C) and elevated triglycerides (TGs) is shown in Korean adults. Little is known about the associations between macronutrient intake and lipid abnormalities in the Asian population, whose major energy source is carbohydrates.

OBJECTIVE

We examined the associations of dietary carbohydrate and fat intakes with lipid abnormalities in Korean adults.

METHODS

A total of 14,301 adults (5715 men and 8586 women) aged ≥30 years with no diagnosis and treatment for diabetes, hypertension, or dyslipidemia were selected from the 2008 to 2012 Korea National Health and Nutrition Examination Survey data. From the 24-hour recall data, dietary carbohydrate and fat intakes were estimated. Multivariate logistic regression was used to estimate odds ratios for lipid abnormalities, that is, elevated total cholesterol (TC), low HDL-C, high TC to HDL-C ratio, elevated non-HDL-C, elevated LDL cholesterol (LDL-C), and elevated TG across quintiles of dietary carbohydrate and fat intakes.

RESULTS

Percentage of energy from carbohydrate was positively associated with elevated TG and low HDL-C but inversely associated with elevated TC and elevated LDL-C in both men and women. Energy-adjusted carbohydrate intake also showed a positive association with low HDL-C. Dietary fat intakes had the opposite associations with lipid abnormalities than results for carbohydrate.

CONCLUSION

High carbohydrate diet is undesirable with regard to increased TG and reduced HDL-C despite the benefit for LDL-C. Dietary strategies emphasizing appropriate macronutrient intakes by the type of lipid abnormalities are recommended for the prevention of cardiovascular disease in Korean adults.

Quality of diet and mortality among Japanese men and women: Japan Public Health Center based prospective study

OBJECTIVE

To examine the association between adherence to the Japanese Food Guide Spinning Top and total and cause specific mortality.

DESIGN

Large scale population based prospective cohort study in Japan with follow-up for a median of 15 years.

SETTING

11 public health centre areas across Japan.

PARTICIPANTS

36,624 men and 42,970 women aged 45-75 who had no history of cancer, stroke, ischaemic heart disease, or chronic liver disease.

MAIN OUTCOME MEASURES

Deaths and causes of death identified with the residential registry and death certificates.

RESULTS

Higher scores on the food guide (better adherence) were associated with lower total mortality; the multivariable adjusted hazard ratios (95% confidence interval) of total mortality for the lowest through highest scores were 1.00, 0.92 (0.87 to 0.97), 0.88 (0.83 to 0.93), and 0.85 (0.79 to 0.91) (P<0.001 for trend) and the multivariable adjusted hazard ratio associated with a 10 point increase in food guide scores was 0.93 (0.91 to 0.95; P<0.001 for trend). This score was inversely associated with mortality from cardiovascular disease (hazard ratio associated with a 10 point increase 0.93, 0.89 to 0.98; P=0.005 for trend) and particularly from cerebrovascular disease (0.89, 0.82 to 0.95; P=0.002 for trend). There was some evidence, though not significant, of an inverse association for cancer mortality (0.96, 0.93 to 1.00; P=0.053 for trend).

CONCLUSION

Closer adherence to Japanese dietary guidelines was associated with a lower risk of total mortality and mortality from cardiovascular disease, particularly from cerebrovascular disease, in Japanese adults.

Dietary intake of fats and fatty acids in the Korean population: Korea National Health and Nutrition Examination Survey, 2013

BACKGROUND/OBJECTIVES

The aim of this study was to estimate average total fat and fatty acid intakes as well as identify major food sources using data from the Korea National Health and Nutrition Examination Survey (KNHANES) VI-1 (2013).

SUBJECTS/METHODS

Total fat and fatty acid intakes were estimated using 24-hour dietary recall data on 7,048 participants aged ≥ 3 years from the KNHANES VI-1 (2013). Data included total fat, saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), polyunsaturated fatty acid (PUFA), n-3 fatty acid (n-3 FA), and n-6 fatty acid (n-6 FA) levels. Population means and standard errors of the mean were weighted in order to produce national estimates and separated based on sex, age, income, as well as residential region. Major food sources of fat, SFA, MUFA, PUFA, n-3 FA, and n-6 FA were identified based on mean consumption amounts of fat and fatty acids in each food.

RESULTS

The mean intake of total fat was 48.0 g while mean intakes of SFA, MUFA, PUFA, n-3 FA, and n-6 FA were 14.4 g, 15.3 g, 11.6 g, 1.6 g, and 10.1 g, respectively. Intakes of MUFA and SFA were each higher than that of PUFA in all age groups. Pork was the major source of total fat, SFA, and MUFA, and soybean oil was the major source of PUFA. Milk and pork were major sources of SFA in subjects aged 3-11 years and ≥ 12 years, respectively. Perilla seed oil and soybean oil were main sources of n-3 FA in subjects aged ≥ 50 years and aged < 50 years, respectively.

CONCLUSIONS

Estimation of mean fatty acid intakes of this study using nationally represented samples of the Korean population could be useful for developing and evaluating national nutritional policies.

Intake of saturated and trans unsaturated fatty acids and risk of all cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies

OBJECTIVE

To systematically review associations between intake of saturated fat and trans unsaturated fat and all cause mortality, cardiovascular disease (CVD) and associated mortality, coronary heart disease (CHD) and associated mortality, ischemic stroke, and type 2 diabetes.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, Embase, Cochrane Central Registry of Controlled Trials, Evidence-Based Medicine Reviews, and CINAHL from inception to 1 May 2015, supplemented by bibliographies of retrieved articles and previous reviews.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Observational studies reporting associations of saturated fat and/or trans unsaturated fat (total, industrially manufactured, or from ruminant animals) with all cause mortality, CHD/CVD mortality, total CHD, ischemic stroke, or type 2 diabetes.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted data and assessed study risks of bias. Multivariable relative risks were pooled. Heterogeneity was assessed and quantified. Potential publication bias was assessed and subgroup analyses were undertaken. The GRADE approach was used to evaluate quality of evidence and certainty of conclusions.

RESULTS

For saturated fat, three to 12 prospective cohort studies for each association were pooled (five to 17 comparisons with 90,501-339,090 participants). Saturated fat intake was not associated with all cause mortality (relative risk 0.99, 95% confidence interval 0.91 to 1.09), CVD mortality (0.97, 0.84 to 1.12), total CHD (1.06, 0.95 to 1.17), ischemic stroke (1.02, 0.90 to 1.15), or type 2 diabetes (0.95, 0.88 to 1.03). There was no convincing lack of association between saturated fat and CHD mortality (1.15, 0.97 to 1.36; P=0.10). For trans fats, one to six prospective cohort studies for each association were pooled (two to seven comparisons with 12,942-230,135 participants). Total trans fat intake was associated with all cause mortality (1.34, 1.16 to 1.56), CHD mortality (1.28, 1.09 to 1.50), and total CHD (1.21, 1.10 to 1.33) but not ischemic stroke (1.07, 0.88 to 1.28) or type 2 diabetes (1.10, 0.95 to 1.27). Industrial, but not ruminant, trans fats were associated with CHD mortality (1.18 (1.04 to 1.33) v 1.01 (0.71 to 1.43)) and CHD (1.42 (1.05 to 1.92) v 0.93 (0.73 to 1.18)). Ruminant trans-palmitoleic acid was inversely associated with type 2 diabetes (0.58, 0.46 to 0.74). The certainty of associations between saturated fat and all outcomes was "very low." The certainty of associations of trans fat with CHD outcomes was "moderate" and "very low" to "low" for other associations.

CONCLUSIONS

Saturated fats are not associated with all cause mortality, CVD, CHD, ischemic stroke, or type 2 diabetes, but the evidence is heterogeneous with methodological limitations. Trans fats are associated with all cause mortality, total CHD, and CHD mortality, probably because of higher levels of intake of industrial trans fats than ruminant trans fats. Dietary guidelines must carefully consider the health effects of recommendations for alternative macronutrients to replace trans fats and saturated fats.

Hemoglobin a1c levels and the risk of cardiovascular disease in people without known diabetes: a population-based cohort study in Japan

High hemoglobin A1c (HbA1c) levels are strongly associated with an increased risk of cardiovascular disease (CVD) in people with and without diabetes. However, information regarding the relationship between low HbA1c levels and the risk of CVD among people without known diabetes is limited. The aim of this large-scale, prospective, population-based cohort study was to clarify the association between HbA1c levels and CVD risk among people without known diabetes.We followed-up 10,980 men and 18,079 women (46-80 years old and free of CVD and cancer at baseline) in the Japan Public Health Center-based Prospective Study. Using Cox models, we estimated the hazard ratios for CVD risk with adjustments for age, sex, geographic areas, body mass index, smoking status, sports and physical exercise, alcohol intake, systolic blood pressure, non-high-density lipoprotein cholesterol, and high-density lipoprotein cholesterol.During the median follow-up of 9.4 years, 935 CVD events (770 strokes and 165 coronary heart diseases) occurred. We observed a nonlinear association between HbA1c levels and CVD risk in participants without known diabetes. Compared with HbA1c levels of 5.0 to 5.4% (31-36 mmol/mol), the hazard ratios for CVD in participants without known diabetes were 1.50 (95% confidence interval: 1.15-1.95), 1.01 (0.85-1.20), 1.04 (0.82-1.32), and 1.77 (1.32-2.38) for HbA1c levels of <5.0% (<31 mmol/mol), 5.5 to 5.9% (37-41 mmol/mol), 6.0 to 6.4% (42-47 mmol/mol), and ≥6.5% (≥48 mmol/mol), respectively (P value for nonlinear trend: <0.001). In addition, the hazard ratio for CVD was 1.81 (1.43-2.29) in patients with known diabetes compared with participants with HbA1c levels of 5.0 to 5.4% and without known diabetes. This nonlinear relation persisted after excluding people with kidney dysfunction, liver dysfunction, anemia, body mass index <18.5 kg/m, or early events within 3 years of follow-up (P value for nonlinear trend: <0.01 for all tests).In conclusion, both low and high levels of HbA1c were associated with a higher risk of CVD in a Japanese general population without known diabetes.

Saturated fat intake and cardiovascular disease in Japanese population

The evidence for the impact of saturated fat intake on cardiovascular disease remains inconsistent. One reason for this inconsistency may be the large difference in the distribution of saturated fat intake between the East and West. In this review, we focus on the published literature on this topic among Japanese population. Three studies have examined the link between saturated fat intake and intraparenchymal hemorrhage, consistently showing an inverse association. However, the association for ischemic stroke is less clear, although it is generally inverse. As for myocardial infarction, the findings in Japanese studies are inconsistent, as are those of Western studies. The JPHC study, however, found a positive association, the first report in Asia. Taken together with the results of the JPHC and Western studies, a saturated fat intake of around 20 g/day (approximately 10% of total energy) may be optimal, which corresponds to 200 g of milk a day and 150 g of meat every other day.

Saturated Fats Versus Polyunsaturated Fats Versus Carbohydrates for Cardiovascular Disease Prevention and Treatment

The effects of saturated fatty acids (SFAs) on cardiovascular disease (CVD) risk are modulated by the nutrients that replace them and their food matrices. Replacement of SFAs with polyunsaturated fatty acids has been associated with reduced CVD risk, although there is heterogeneity in both fatty acid categories. In contrast, replacement of SFAs with carbohydrates, particularly sugar, has been associated with no improvement or even a worsening of CVD risk, at least in part through effects on atherogenic dyslipidemia, a cluster of traits including small, dense low-density lipoprotein particles. The effects of dietary SFAs on insulin sensitivity, inflammation, vascular function, and thrombosis are less clear. There is growing evidence that SFAs in the context of dairy foods, particularly fermented dairy products, have neutral or inverse associations with CVD. Overall dietary patterns emphasizing vegetables, fish, nuts, and whole versus processed grains form the basis of heart-healthy eating and should supersede a focus on macronutrient composition.

Circulating biomarkers of dairy fat and risk of incident stroke in U.S. men and women in 2 large prospective cohorts

BACKGROUND

Previous observational studies of self-reported dairy product consumption and stroke risk have reported mixed findings. Few studies have used circulating biomarkers that provide objective measures of dairy fat intake.

OBJECTIVES

We tested the hypothesis that the circulating biomarkers of dairy fat, pentadecanoic acid (15:0), heptadecanoic acid (17:0), and trans palmitoleate (trans 16:1n-7), were associated with lower incidence of stroke, especially ischemic stroke. Secondarily, we evaluated 14:0, which is obtained from dairy products and beef, and also endogenously synthesized.

DESIGN

In participants from 2 large US cohorts (the Health Professionals Follow-Up Study: 51,529 men; the Nurses' Health Study: 121,700 women) with stored blood samples in 1993-1994 (n = 18,225) and 1989-1990 (n = 32,826), respectively, we prospectively identified 594 incident stroke cases (median follow-up: 8.3 y) and matched them 1:1 to risk-set-sampled control subjects by age, sex, race, and smoking. Total plasma and red blood cell (RBC) fatty acids were measured by using gas-liquid chromatography. Covariates were assessed by using validated questionnaires. Stroke events and subtypes were adjudicated by using medical records or other supporting documentation. We used conditional logistic regression to estimate associations of fatty acids with incident stroke, and cohort-specific findings were combined by inverse-variance weights.

RESULTS

After adjustment for demographic characteristics, lifestyle, cardiovascular disease risk factors, diet, and other circulating fatty acids, no significant associations with total stroke were seen for plasma 15:0 (pooled HR for highest compared with lowest quartiles: 0.85; 95% CI: 0.54, 1.33), 17:0 (0.99; 0.67, 1.49), trans 16:1 n-7 (0.89; 0.55, 1.45), or 14:0 (1.05; 0.62, 1.78). Results were similar for ischemic and hemorrhagic stroke subtypes, for RBC fatty acids, and in several different sensitivity analyses.

CONCLUSION

In 2 large prospective cohorts, circulating biomarkers of dairy fat were not significantly associated with stroke.

Plasma fatty acid composition and incident ischemic stroke in middle-aged adults: the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

The association of individual fatty acids with ischemic stroke has not been thoroughly studied, and results have been inconsistent. Few prospective studies have systematically explored the association of biomarkers of fatty acid intake with stroke. The aim of this study was to explore which individual plasma fatty acids would be associated with higher risk of ischemic stroke among whites.

METHODS

We studied 3,870 white men and women from the Minneapolis field center of the Atherosclerosis Risk in Communities (ARIC) Study, aged 45-64 years at baseline (1987-1989), who had plasma cholesterol ester (CE) and phospholipid (PL) fatty acids measured. Participants were followed through 2008 for incident ischemic stroke. Hazard ratios (HRs) with 95% confidence intervals (CIs) across quartiles of each fatty acid, measured as the percentage of total fatty acids, were calculated using the Cox proportional hazards model.

RESULTS

During a maximum of 22 years of follow-up, we identified 168 cases of ischemic stroke. After adjustment for age and sex, plasma levels of saturated fatty acids were associated positively: HR (95% CI) of the highest versus the lowest quartile for CE fraction was 1.93 (1.23-3.04, p for trend = 0.01) and that for PL fraction was 1.64 (1.05-2.57, p for trend = 0.03). There was also a positive linear association with monounsaturated fatty acids, especially with palmitoleic acid: HR (95% CI) of the highest versus the lowest quartile for CE fraction was 1.86 (1.20-2.87, p for trend = 0.003) and that for PL fraction was 1.52 (0.99-2.34, p for trend = 0.005). No associations of ω-3 and ω-6 polyunsaturated fatty acids with ischemic stroke were observed, but linoleic acid was inversely and nonlinearly associated with ischemic stroke: HR (95% CI) of the highest versus the lowest quartile for CE fraction was 0.64 (0.43-0.97, p for trend = 0.13) and that for PL fraction was 0.69 (0.45-1.05, p for trend = 0.24). These associations were generally unchanged after adjustment for cardiovascular risk factors.

CONCLUSIONS

In this US cohort of whites, we found significant positive associations of plasma saturated and monounsaturated fatty acids, especially of palmitoleic acid, with ischemic stroke. We also found an inverse nonlinear association between linoleic acid and ischemic stroke.