Red meat consumption, risk of incidence of cardiovascular disease and cardiovascular mortality, and the dose-response effect: Protocol for a systematic review and meta-analysis of longitudinal cohort studies

Global Association between Traditional Japanese Diet Score and All-Cause, Cardiovascular Disease, and Total Cancer Mortality: A Cross-Sectional and Longitudinal Ecological Study

OBJECTIVE

Studies conducted on Japanese people have suggested that a traditional Japanese diet contributes to good health, longevity, and protection against several non-communicable diseases. However, it is unknown whether traditional Japanese dietary patterns are associated with all-cause mortality, cardiovascular disease, and cancer mortality globally. The purpose of this cross-sectional and longitudinal ecological study is to clarify the global association between the traditional Japanese diet score (TJDS) and all-cause, cardiovascular disease, and total cancer mortality.

METHODS

Data on food supply and all-cause mortality, cardiovascular disease mortality, total cancer mortality, and covariables by country were obtained from a relevant internationally available database. TJDS by country was calculated from eight food groups and the total score ranged from -8 to 8, with higher scores indicating greater adherence to a traditional Japanese diet. We evaluated the cross-sectional and 10-year longitudinal association between TJDS and all-cause, cardiovascular disease, and total cancer mortality using 2009 as the baseline in 142 countries with populations of more than one million. A cross-sectional analysis and a longitudinal analysis were performed using three general linear models or three linear mixed models with different covariables.

RESULTS

In cross-sectional models controlled for fully-adjusted covariables, TJDS was negatively associated with all-cause mortality (β ± standard error; -43.819 ± 11.741, p < 0.001), cardiovascular disease mortality (-22.395 ± 4.638, p < 0.001), and total cancer mortality (-3.893 ± 1.048, p < 0.001). In 10-year longitudinal models controlled for fully-adjusted covariables, TJDS was significantly negatively associated with all-cause mortality (-31.563 ± 7.695, p < 0.001), cardiovascular disease mortality (-16.249 ± 4.054, p < 0.001), and total cancer mortality (-3.499 ± 0.867, p < 0.001).

CONCLUSIONS

This cross-sectional and longitudinal ecological study suggests that the traditional Japanese diet is associated with lower all-cause mortality, cardiovascular disease mortality, and total cancer mortality, worldwide.

Population food intake clusters and cardiovascular disease incidence: a Bayesian quantifying of a prospective population-based cohort study in a low and middle-income country

Aims

This study was designed to explore the relationship between cardiovascular disease incidence and population clusters, which were established based on daily food intake.

Methods

The current study examined 5,396 Iranian adults (2,627 males and 2,769 females) aged 35 years and older, who participated in a 10-year longitudinal population-based study that began in 2001. The frequency of food group consumption over the preceding year (daily, weekly, or monthly) was assessed using a 49-item qualitative food frequency questionnaire (FFQ) administered via a face-to-face interview conducted by an expert dietitian. Participants were clustered based on their dietary intake by applying the semi-parametric Bayesian approach of the Dirichlet Process. In this approach, individuals with the same multivariate distribution based on dietary intake were assigned to the same cluster. The association between the extracted population clusters and the incidence of cardiovascular diseases was examined using Cox proportional hazard models.

Results

In the 10-year follow-up, 741 participants (401 men and 340 women) were diagnosed with cardiovascular diseases. Individuals were categorized into three primary dietary clusters: healthy, unhealthy, and mixed. After adjusting for potential confounders, subjects in the unhealthy cluster exhibited a higher risk for cardiovascular diseases [Hazard Ratio (HR): 2.059; 95% CI: 1.013, 4.184] compared to those in the healthy cluster. In the unadjusted model, individuals in the mixed cluster demonstrated a higher risk for cardiovascular disease than those in the healthy cluster (HR: 1.515; 95% CI: 1.097, 2.092). However, this association was attenuated after adjusting for potential confounders (HR: 1.145; 95% CI: 0.769, 1.706).

Conclusion

The results have shown that individuals within an unhealthy cluster have a risk that is twice as high for the incidence of cardiovascular diseases. However, these associations need to be confirmed through further prospective investigations.

Total meat (flesh) supply may be a significant risk factor for cardiovascular diseases worldwide

Consumption of red meat instead of white meat has typically been associated with cardiovascular diseases (CVDs). Reflecting actual diet patterns, this study explored the role of total meat (red + white) in predicting CVD incidence. Data from 217 countries were extracted from United Nations agencies for the analyses in five steps. Bivariate correlations were applied to examine the relationship between total meat and CVD incidence globally and regionally. Partial correlation was applied to identify that total meat was an independent predictor of CVD incidence while socioeconomic status, obesity, and urbanization were statistically constant. Stepwise linear regression was conducted for selecting the significant predictor of CVD incidence. SPSS 28 and Microsoft Excel were used for correlation analyses. Globally, total meat correlated to CVD incidence strongly and significantly in bivariate correlation models. This relationship remained significant in partial correlation when socioeconomic status, obesity, and urbanization were statistically kept constant. Stepwise multiple regression identified that, second to socioeconomic status, total meat was a significant predictor of CVD incidence. Total meat correlated to CVD incidence in different country groupings. However, the correlations between total meat and CVD incidence were significantly stronger in developing countries than in developed countries. Worldwide, total meat (flesh) consumption correlated to CVD incidence independently, but significantly stronger in developing countries than in developed countries. This correlation is worth exploring further in longitudinal cohort studies.

Saturated Fatty Acid Chain Length and Risk of Cardiovascular Disease: A Systematic Review

The purpose of this systematic review was to evaluate the impact of saturated fatty acid chain lengths on the development of cardiovascular disease (CVD). The importance of replacement macronutrients is also discussed. PubMed, CINAHL, and Cochrane library were searched for relevant prospective cohort studies that measured SFA chain length via diet analysis through October of 2020. A second updated PubMed search was conducted from October 2020 to 7 August 2022. Five prospective cohort studies were added. All studies used food frequency questionnaires to assess dietary intake. For all five added studies, the main sources of saturated fat were palmitic and steric acid from meat and cheese. Most studies discovered an association with increased risk of CVD and long-chain saturated fatty acid intake, as well as a neutral (potentially beneficial) association with short- and medium-chain saturated fatty acids. Isocaloric substitutions were associated with a higher risk for CVD when saturated fats were replaced with refined carbohydrates and protein from meat, but a reduced or neutral impact when relaced with plant-based protein, unsaturated fat, or complex carbohydrates. When examining the impact of diet on CVD risk, it is critical to consider the macronutrient replacing saturated fat as well as the saturated fat chain length, whole foods, and diet patterns on CVD risk. The studies included in this review suggest that LCSFA (C12-18) may increase the risk for CVD development, while SCFA and MCFA (C4--C10) may be more beneficial or neutral.

Associations between Cardiovascular Outcomes and Rheumatoid Arthritis: A Nationwide Population-Based Cohort Study

Despite a growing burden posed by cardiovascular disease (CVD) in rheumatoid arthritis (RA) patients, large-scale studies on the association between the characteristics of RA patients and CVD risks and studies adjusted for various confounding factors are lacking. In this large-scale nationwide cohort study, we aimed to investigate the association between CVD risk and RA and factors that may increase CVD risk using a dataset provided by the Korean National Health Insurance Service (NHIS). We enrolled 136,469 patients with RA who participated in national health examinations within two years of RA diagnosis between 2010 and 2017 and non-RA controls matched by age and sex (n = 682,345). The outcome was the occurrence of myocardial infarction (MI) or stroke. MI was defined as one hospitalization or two outpatient visits with ICD-10-CM codes I21 or I22. Stroke was defined as one hospitalization with ICD-10-CM codes I63 or I64 and a claim for brain imaging (CT or MRI). The Cox proportional hazard model and Kaplan-Meier curve were used for analysis. The mean follow-up duration was 4.7 years, and the incidence rate of CVD was higher in the RA group than the control group (MI: 3.20 vs. 2.08; stroke: 2.84 vs. 2.33 per 1000 person-years). The risk of MI and stroke was about 50% and 20% higher, respectively, in RA patients. The association between RA and CVD was prominent in females after adjusting for confounding variables. The association between RA and risk of MI was significant in individuals without DM. Therefore, appropriate screening for CVD is important in all RA patients including females and younger patients.

A Systematic Review and Meta-Analysis of Advanced Biomarkers for Predicting Incident Cardiovascular Disease among Asymptomatic Middle-Aged Adults

Cardiovascular disease (CVD) continues as the most important cause of mortality. Better risk screening and prediction are needed to reduce the cardiovascular disease burden. The aim of the study was to assess the role of serum biomarkers in the prediction of CVD among asymptomatic middle-aged adults with no prior CVD history. A systematic review and meta-analysis were carried out using literature from PubMed and following PRISMA reporting guidelines. Twenty-five studies met our inclusion criteria and were included in the systematic review. The most commonly studied biomarker was high-sensitivity C reactive protein (hs-CRP) (10 studies), which showed that higher hs-CRP levels are associated with an increased risk of subsequent CVD events and mortality. In addition, several less-studied biomarkers (N-terminal pro-brain natriuretic peptide (NT-proBNP), fibrinogen, gamma-glutamyl transferase (GGT), and others) also showed significant associations with greater future risk of CVD. A meta-analysis was possible to perform for hs-CRP and NT-proBNP, which showed statistically significant results for the ability of hs-CRP (hazard ratio (HR) 1.19, (95% CI: 1.09−1.30), p < 0.05) and NT-proBNP (HR 1.22, (1.13−1.32), p < 0.05) to predict incident CVD among middle-aged adults without a prior CVD history or symptoms. Several serum biomarkers, particularly hs-CRP and NT-proBNP, have the potential to improve primary CVD risk prevention among asymptomatic middle-aged adults.

Lowering n-6/n-3 Ratio as an Important Dietary Intervention to Prevent LPS-Inducible Dyslipidemia and Hepatic Abnormalities in ob/ob Mice

Obesity is closely associated with low-grade chronic and systemic inflammation and dyslipidemia, and the consumption of omega-3 polyunsaturated fatty acids (n-3 PUFAs) may modulate obesity-related disorders, such as inflammation and dyslipidemia. An emerging research question is to understand the dietary intervention strategy that is more important regarding n-3 PUFA consumption: (1) a lower ratio of n-6/n-3 PUFAs or (2) a higher amount of n-3 PUFAs consumption. To understand the desirable dietary intervention method of n-3 PUFAs consumption, we replaced lard from the experimental diets with either perilla oil (PO) or corn oil (CO) to have identical n-3 amounts in the experimental diets. PO had a lower n-6/n-3 ratio, whereas CO contained higher amounts of PUFAs; it inherently contained relatively lower n-3 but higher n-6 PUFAs than PO. After the 12-week dietary intervention in ob/ob mice, dyslipidemia was observed in the normal chow and CO-fed ob/ob mice; however, PO feeding increased the high density lipoprotein-cholesterol (HDL-C) level; further, not only did the HDL-C level increase, the low density lipoprotein-cholesterol (LDL-C) and triglyceride (TG) levels also decreased significantly after lipopolysaccharide (LPS) injection. Consequently, extra TG accumulated in the liver and white adipose tissue (WAT) of normal chow- or CO-fed ob/ob mice after LPS injection; however, PO consumption decreased serum TG accumulation in the liver and WAT. PUFAs replacement attenuated systemic inflammation induced by LPS injection by increasing anti-inflammatory cytokines but inhibiting pro-inflammatory cytokine production in the serum and WAT. PO further decreased hepatic inflammation and fibrosis in comparison with the ND and CO. Hepatic functional biomarkers (aspartate aminotransferase (AST) and alanine transaminase (ALT) levels) were also remarkably decreased in the PO group. In LPS-challenged ob/ob mice, PO and CO decreased adipocyte size and adipokine secretion, with a reduction in phosphorylation of MAPKs compared to the ND group. In addition, LPS-inducible endoplasmic reticulum (ER) and oxidative stress decreased with consumption of PUFAs. Taken together, PUFAs from PO and CO play a role in regulating obesity-related disorders. Moreover, PO, which possesses a lower ratio of n-6/n-3 PUFAs, remarkably alleviated metabolic dysfunction in LPS-induced ob/ob mice. Therefore, an interventional trial considering the ratio of n-6/n-3 PUFAs may be desirable for modulating metabolic complications, such as inflammatory responses and ER stress in the circulation, liver, and/or WAT.

Reconsidering Meat Intake and Human Health: A Review of Current Research

Meat consumption is gradually increasing and its impact on health has attracted widespread attention, resulting in epidemiological studies proposing a reduction in meat and processed meat intake. This review briefly summarizes recent advances in understanding the effects of meat or processed meat on human health, as well as the underlying mechanisms. Meat consumption varies widely among individuals, populations, and regions, with higher consumption in developed countries than in developing countries. However, increasing meat consumption may not be the main cause of increasing incidence of chronic disease, since the development of chronic disease is a complex physiological process that involves many factors, including excessive total energy intake and changes in food digestion processes, gut microbiota composition, and liver metabolism. In comparison, unhealthy dietary habits and a sedentary lifestyle with decreasing energy expenditure are factors more worthy of reflection. Meat and meat products provide high-value protein and many key essential micronutrients. In short, as long as excessive intake and overprocessing of meats are avoided, meat remains an indispensable source of nutrition for human health.

Associations of the consumption of unprocessed red meat and processed meat with the incidence of cardiovascular disease and mortality, and the dose-response relationship: A systematic review and meta-analysis of cohort studies

OBJECTIVES

The aim of this study was to examine the associations of unprocessed red meat and processed meat consumption with cardiovascular disease (CVD) incidence and mortality, and the dose-response relationship.

METHODS

Published literature was retrieved through a structured search of 10 electronic databases: MEDLINE/PubMed, Scopus, SciELO, LILACS, ScienceDirect, Web of Science, Cochrane (CENTRAL), WHOLIS, PAHO and Embase, without language or year of publication restrictions. In addition, we searched the references of published studies. This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes: The PRISMA Statement.

RESULTS

Twenty-one prospective cohort studies were included in the systematic review. The CVDs evaluated in the inserted studies were stroke, heart failure (HF) and coronary heart disease (CHD). Considering the heterogeneity found in the studies, for the meta-analysis, 9 articles were included. The results presented in the meta-analysis of the association of consumption of unprocessed red meat and CVD indicated that there was a significant association with total stroke incidence (RR 1.10; 95%; CI 1.01 to 1.19; p = 0.02). There was no association with Ischemic stroke incidence, nor CHD Mortality with consumption of unprocessed red meat. However, for Hemorrhagic Stroke Mortality the assessment in the consumption of unprocessed red meat showed an association of protection for women (RR 0.64; 95%; CI 0.45 to 0.91; p = 0.01). As for the results of the meta-analysis of the association between consumption of processed meat and CVD, they indicated that there was a significant association with total stroke incidence (RR 1.17; 95%; CI 1.08 to 1.26; p < 0.0001). There was no association with Ischemic stroke, nor with CHD Mortality with consumption of processed meat. Some studies that showed no association of risk, presented a significant linear trend dose response for the association of the consumption of unprocessed red meat (Bernstein et al. 2010; Nagao et al. 2012) or processed meat (Bernstein et al. 2012) and CVD.

CONCLUSION

According to the results found in the meta-analysis, the consumption of unprocessed red meat and processed meat are associated with the incidence of stroke, however, no positive association was observed in relation to mortality from CVD. This systematic review and meta-analysis protocol was registered on the PROSPERO (number: CRD42019100914).

Healthy Aging: Comparative Analysis of Local Perception and Diet in Two Health Districts of Côte d’Ivoire and Japan

Context: Good health and longevity depend on dynamic interactions between biological, social, psychological, and environmental factors. Aging is globally a big challenge, particularly with the demographic transition, including population growth, and an emerging burden to society. Knowledge, behavior, diet, and consumption of animal source food were related to aging and emerged as the key factors modulating healthy aging.

Objective: The study was designed to understand the main healthy aging factors, such as knowledge, social network, and diet of elders, and to derive mutual learning from it for healthy aging.

Methods: A qualitative approach has been applied to explore health-related knowledge, attitude, and diet of elders from Ebetsu (Japan) and Tiassalé (Côte d’Ivoire) health districts, using focus group discussions and comparative context analysis between high- and low-income countries.

Results: The study shows that living longer is a common feature of people in Japan compared to Côte d’Ivoire, where the life expectancy is still low. Both groups of elders have social networks that support them, and both offer their gained experience to society. While Japanese elders depend on pension and insurance for income and medical treatments, Ivorians depend mostly on their children and social network in old age. The worries of elders differ between the two regions. In Ebetsu, elder members of the community are concerned about the future burden they pose for the younger generation if they develop ill-health, making them more resilient to aging. In Taabo, elders are considered to be culturally and socially useful to the society. Elders in Ebetsu pointed out that for healthy aging, education on diet at a younger age, physical activities, and access to basic social services are the key aspects. This was not observed in Taabo’s context. Being inactive and dependent on others were described as the most worrying situations for elders in Ebetsu, as it is perceived to increase the risk of non-communicable diseases and anxiety. Elders in Ebetsu have good knowledge on what constitutes a healthy diet, and they believe that diversifying their diet, reducing portions, and substituting red meat with good animal and vegetable proteins are best eating practices to maintain good health. In Côte d’Ivoire, the diet is imbalanced and the whole family consumes the same meal made mainly with high-energy staples and little protein. However, it is observed in both societies that adopting a good diet is very expensive.

Conclusion: The consciousness of aging is universal, but healthy aging varies according to the social systems, education, and knowledge on diet transition. Physical activities, protein–energy balance in diet, and social networks are the key for healthy aging in both contexts. The challenge is to find ways to increase knowledge regarding healthy aging and to strengthen the support system so that healthy aging becomes affordable.

Obesity and the increased risk for COVID-19: mechanisms and nutritional management

The global COVID-19 (coronavirus disease 2019) pandemic has become a complex problem that overlaps with a growing public health problem, obesity. Obesity alters different components of the innate and adaptive immune responses, creating a chronic and low-grade state of inflammation. Nutritional status is closely related to a better or worse prognosis of viral infections. Excess weight has been recognised as a risk factor for COVID-19 complications. In addition to the direct risk, obesity triggers other diseases such as diabetes and hypertension, increasing the risk of severe COVID-19. The present review explains the diets that induce obesity and the importance of different foods in this process. We also review tissue disruption in obesity, leading to impaired immune responses and the possible mechanisms by which obesity and its co-morbidities increase COVID-19 morbidity and mortality. Nutritional strategies that support the immune system in patients with obesity and with COVID-19 are also discussed in light of the available data, considering the severity of the infection. The discussions held may contribute to combating this global emergency and planning specific public health policy.

Effects of Plant-Based Diets on Weight Status in Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

Excessive adiposity is a major risk factor for type 2 diabetes (T2D), and dietary patterns are important determinants of weight status. Plant-based dietary patterns (PBDs) are known for their therapeutic effects on T2D. The aim is to systematically review RCTs to investigate the effects of various PBDs compared to regular meat-eating diets (RMDs), in individuals who normally consume a RMD on body weight, BMI, and waist circumference in T2D. RCTs investigating PBDs and body weight, BMI, WC for ≥6 weeks in adults with T2D since 1980 were eligible for inclusion. Seven trials (n = 269) were included in the meta-analysis using random-effects models and expressed as MD (95%Cls). Compared to RMDs, PBDs significantly lowered body weight (-2.35 kg, 95% CI: -3.51, -1.19, p < 0.001), BMI (-0.90 kg/m2, 95% CI: -1.42, -0.38, p = 0.001) and WC (-2.41 cm, 95% CI: -3.72, -1.09, p < 0.001). PBDs alone significantly reduced body weight by 5.1% (-4.95 kg, 95% CI: -7.34, -2.55, p < 0.001), BMI by 5.4% (-1.87 kg/m2, 95% CI: -2.78, -0.95, p < 0.001) and WC by 4.3%(-4.23, 95% CI: -6.38, -2.07, p < 0.001). Interventions not limiting energy intake led to a significant reduction in body weight (-2.54 kg, 95% CI: -4.16, -0.92, p < 0.005) and BMI (-0.91 kg/m2, 95% CI: -1.56, -0.25, p < 0.005). Trials ≥16 weeks had a pronounced reduction in body weight (-2.93 kg, 95% CI: -5.00, -0.87, p = 0.005) and BMI (-1.13 kg/m2, 95% CI: -1.89, -0.38, p < 0.005). These findings provide evidence for the implementation of PBDs for better management of central adiposity in individuals with T2D.

Changes in plasma fatty acids and related biomarkers during transition to an exclusively plant- and fish-based diet in healthy adults

OBJECTIVE

The aim of this study was to examine the time scale of plasma fatty acid changes during transition to an exclusively plant- and fish-based diet in healthy individuals and determine whether there are associated alterations in arachidonic acid (ARA)-derived inflammatory mediators, estimated stearoyl coenzyme A desaturase (SCD) activity, and blood pressure.

METHODS

In pursuit of a religious fast, 36 adults abstained  from eating poultry, meat, dairy products, and eggs, while increasing fish intake for 6 wk. Participants were assessed 1 wk before (W0) and 1 (W1) and 6 (W6) weeks after the diet change.

RESULTS

By W6, fasting plasma long-chain ω-3 polyunsaturated fatty acids (ω-3 LC-PUFAs); docosahexaenoic (DHA) and eicosapentaenoic (EPA) had increased (+67% and +73%, respectively; P ≤ 0.001), with early rise of DHA (+22%), but not EPA at W1.The ω-3 index (sum of DHA and EPA as a percent of total fatty acids) increased from 2.1% to 3.4%. ARA decreased progressively (W1, -9%; W6, -16%; P < 0.001). ARA precursors γ-linolenic and dihomo-γ-linolenic acids also decreased, without changes in the ARA-derived mediators prostaglandin-E2 and leukotriene-B4. Myristic acid decreased at W1 (-37%) and W6 (-40%). There was no consistent change in SCD indices. At W6, systolic and diastolic blood pressure had declined by 8 and 5 mm Hg, respectively (P ≤ 0.013).

CONCLUSIONS

Shifting to a plant- and fish-based diet produces rapid and sustained increases in ω-3 LC-PUFAs and decreases the ω-6 PUFA ARA and its precursors, consistent with a cardio-protective profile. The rapid response suggests that these biomarkers may be useful for assessment of diet interventions.

Overview of Non-Alcoholic Fatty Liver Disease (NAFLD) and the Role of Sugary Food Consumption and Other Dietary Components in Its Development

NAFLD is the world's most common chronic liver disease, and its increasing prevalence parallels the global rise in diabetes and obesity. It is characterised by fat accumulation in the liver evolving to non-alcoholic steatohepatitis (NASH), an inflammatory subtype that can lead to liver fibrosis and cirrhosis. Currently, there is no effective pharmacotherapeutic treatment for NAFLD. Treatment is therefore based on lifestyle modifications including changes to diet and exercise, although it is unclear what the most effective form of intervention is. The aim of this review, then, is to discuss the role of specific nutrients and the effects of different dietary interventions on NAFLD. It is well established that an unhealthy diet rich in calories, sugars, and saturated fats and low in polyunsaturated fatty acids, fibre, and micronutrients plays a critical role in the development and progression of this disease. However, few clinical trials have evaluated the effects of nutrition interventions on NAFLD. We, therefore, summarise what is currently known about the effects of macronutrients, foods, and dietary patterns on NAFLD prevention and treatment. Most current guidelines recommend low-calorie, plant-based diets, such as the Mediterranean diet, as the most effective dietary pattern to treat NAFLD. More clinical trials are required, however, to identify the best evidence-based dietary treatment approach.