Association of vegetarian diet with inflammatory biomarkers: a systematic review and meta-analysis of observational studies

The Association Between Overall, Healthy, and Unhealthy Plant-Based Diet Index and Risk of Prediabetes and Type 2 Diabetes Mellitus: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies

CONTEXT

The global incidence of prediabetes and type 2 diabetes mellitus (T2DM) has increased substantially in recent years. Among the established, modifiable lifestyle factors associated with favorable prediabetes and T2DM risk, healthy dietary patterns have attracted considerable attention.

OBJECTIVE

The association between adherence to plant-based dietary pattern indices (PDIs), including the overall PDI (O-PDI), healthy PDI (H-PDI), and unhealthy PDI (U-PDI), and the risk of prediabetes and T2DM was investigated in this study.

DATA SOURCES

A literature search was conducted of the PubMed/Medline, Scopus, and Web of Sciences databases from their inception to February 2024. A systematic review and meta-analysis were conducted using random effects models and dose-response analyses. The Cochran Q test and the I2 statistic were used to evaluate heterogeneity between studies.

DATA EXTRACTION

A total of 16 publications, with data on a total of 721 012 participants, were identified for the meta-analysis.

DATA ANALYSIS

According to a pooled analysis, compared with the lowest category of O-PDI and H-PDI adherence, the highest category was associated with a 14% and 19% reduction in T2DM risk, respectively, for O-PDI (effect size [ES] = 0.86; 95%CI, 0.82-0.90; I2 = 57.7) and H-PDI (ES = 0.81; 95%CI, 0.75-0.88; I2 = 82.6). Greater adherence to U-PDI was significantly associated with an 10% increase in the risk of T2DM (ES = 1.10; 95%CI, 1.04-1.16). Consistent associations were found within the predetermined subgroups. As well, there was a nonlinear inverse association between O-PDI, H-PDI, and T2DM risk. No significant association was found between adherence to O-PDI (ES = 0.87; 95%CI, 0.75-1.01; I2 = 68%), H-PDI (ES = 0.99; 95%CI, 0.87-1.13; I2 = 0.0%), and U-PDI (ES = 1.09; 95%CI, 0.94-1.21; I2 = 22.9%) and risk of prediabetes.

CONCLUSION

These findings underscore the importance of dietary selections within the framework of a plant-based dietary pattern, particularly when incorporating healthful, plant-based foods, which may have potential benefits in reducing the T2DM risk.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023459851.

Cardiovascular health and cancer risk associated with plant based diets: An umbrella review

CONTEXT

Cardiovascular diseases (CVDs) and cancer are the two main leading causes of death and disability worldwide. Suboptimal diet, poor in vegetables, fruits, legumes and whole grain, and rich in processed and red meat, refined grains, and added sugars, is a primary modifiable risk factor. Based on health, economic and ethical concerns, plant-based diets have progressively widespread worldwide.

OBJECTIVE

This umbrella review aims at assessing the impact of animal-free and animal-products-free diets (A/APFDs) on the risk factors associated with the development of cardiometabolic diseases, cancer and their related mortalities.

DATA SOURCES

PubMed and Scopus were searched for reviews, systematic reviews, and meta-analyses published from 1st January 2000 to 31st June 2023, written in English and involving human subjects of all ages. Primary studies and reviews/meta-analyses based on interventional trials which used A/APFDs as a therapy for people with metabolic diseases were excluded.

DATA EXTRACTION

The umbrella review approach was applied for data extraction and analysis. The revised AMSTAR-R 11-item tool was applied to assess the quality of reviews/meta-analyses.

RESULTS

Overall, vegetarian and vegan diets are significantly associated with better lipid profile, glycemic control, body weight/BMI, inflammation, and lower risk of ischemic heart disease and cancer. Vegetarian diet is also associated with lower mortality from CVDs. On the other hand, no difference in the risk of developing gestational diabetes and hypertension were reported in pregnant women following vegetarian diets. Study quality was average. A key limitation is represented by the high heterogeneity of the study population in terms of sample size, demography, geographical origin, dietary patterns, and other lifestyle confounders.

CONCLUSIONS

Plant-based diets appear beneficial in reducing cardiometabolic risk factors, as well as CVDs, cancer risk and mortality. However, caution should be paid before broadly suggesting the adoption of A/AFPDs since the strength-of-evidence of study results is significantly limited by the large study heterogeneity alongside the potential risks associated with potentially restrictive regimens.

Plant-based and vegetarian diets are associated with reduced obstructive sleep apnoea risk

Introduction

Obstructive sleep apnoea (OSA) and obesity commonly coexist. Weight loss and exercise are recommended management options for OSA. However, most of the current evidence on diet and OSA is focused on calorie restriction rather than diet quality. The aim of the present study was to determine the association of plant-based dietary indices (PDI) with OSA risk.

Methods

Cross-sectional data from 14 210 participants of the National Health and Nutrition Examination Survey who provided dietary information using the 24-hour recall method were used. PDI - including healthy (hPDI), unhealthy (uPDI) and pro-vegetarian diet index (PVDI) - were determined. OSA risk was determined using the STOP-BANG questionnaire. Logistic regression was used to determine the relationship between dietary indices and OSA risk.

Results

Higher adherence to PDI (odds ratio (OR)Q5 versus Q1=0.81; 95% confidence interval (CI): 0.66-1.00), hPDI (OR=0.83; 95% CI: 0.69-1.01) and PVDI (OR=0.84; 95% CI: 0.68-1.05) was inversely associated with OSA risk, whereas higher consumption of an unhealthy plant-based diet (OR=1.22; 95% CI: 1.00-1.49) was positively associated with OSA. Sex differences in estimates were observed for PDI in males (OR=0.71; 95% CI: 0.56-0.90) versus females (OR=0.93; 95% CI: 0.68-1.28), hPDI in males (OR=0.90; 95% CI: 0.68-1.18) versus females (OR=0.77; 95% CI: 0.54-1.09) and uPDI in males (OR=1.13; 95% CI: 0.89-1.44) versus females (OR=1.42; 95% CI: 1.03-1.97) but not for PVDI.

Conclusions

Higher adherence to a healthy plant-based diet is associated with reduced OSA risk, while an unhealthy plant-based diet has a positive association. The magnitude of these associations differs by sex. Further longitudinal studies are warranted.

Dietary total, plant, and animal protein intake in relation to cardiovascular outcomes and inflammatory factors in elderly men: A cross-sectional study

The source and amount of protein intake may influence cardiovascular and inflammatory risk, especially in elders who are often more vulnerable. However, findings on elders have been contradictory. Therefore, we examined the association between dietary total, plant, and animal protein intake in relation to cardiovascular outcomes and inflammatory factors in elderly men. The present cross-sectional study included 357 elderly men. A validated and reliable food frequency questionnaire (FFQ) was used to assess dietary intake. All biochemical factors including triglycerides (TG), fasting blood sugar (FBS), high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL6), and tumor necrosis factor-α (TNF-α) were measured. Waist circumference (WC) and blood pressure (BP) were also assessed. A significant inverse association was found between animal protein intake and systolic blood pressure (SBP; OR: 0.62; 95% CI: 0.42, 0.91; ptrend = .014). There were significant inverse associations between plant protein intake and WC (OR: 0.34; 95% CI: 0.17, 0.68; ptrend < .001), FBS (OR: 0.51; 95% CI: 0.29, 0.89; ptrend = .018) and Hs-CRP (OR: 0.39; 95% CI: 0.21, 0.70; ptrend = .002). Moreover, significant inverse associations were also found between total protein intake and SBP (OR: 0.54; 95% CI: 0.33, 0.86; ptrend = .010) and total protein and Hs-CRP (OR: 0.50; 95% CI: 0.28, 0.88; ptrend = .015). In elderly men, a high dietary intake of plant protein was associated with lower odds of having high WC, FBS, and Hs-CRP. In addition, high dietary intake of animal protein was associated with higher odds of having a high SBP level, which was explained by higher intake of dairy products.

Regular nutrition consultations reduced risk factors for cardiovascular diseases in adults

OBJECTIVES

This study investigated the effects of regular nutrition consultations on reducing risk factors, including body mass index, body composition, blood pressure, blood lipid profile, blood glucose-related markers, and inflammatory factors for cardiovascular diseases.

METHODS

Data were collected from participants (n = 129) who completed eight dietary consultations and were divided into two groups according to the regularity of the consultations: an irregular group (with irregular consultation intervals; n = 39) and a regular group (accepted consultation once every 3 wk; n = 90).

RESULTS

Compared with the irregular group, the regular group had more significant reductions in cardiovascular disease risk factors, such as body mass index, body fat, triglycerides, total cholesterol, low-density lipoprotein cholesterol, and insulin levels. Moreover, participants with a body mass index ≥ 27 kg/m2 presented significantly obvious improvements in cardiovascular risk factors, such as body weight; body mass index; visceral fat weight; and triglyceride, total cholesterol, low-density lipoprotein cholesterol, glycated hemoglobin, and insulin levels.

CONCLUSION

There is a proven benefit to regular nutrition consultation for adults with risk factors of cardiovascular diseases, particularly those who are obese.

Immune checkpoint molecules B7-1 and B7-H1 as predictive markers of pre-eclampsia: A case-control study in a Ghana

BACKGROUND/AIM

Immune tolerance in the fetal-maternal junction is maintained by a balance in the Th1/Th2 system. Th1-type immunity is associated with pro-inflammatory cytokines and immune checkpoint molecules (ICMs) such as B7-H1, while Th2-type immunity is characterized by anti-inflammatory cytokines and ICMs such as B7-1. Any imbalance in the Th1/Th2 immune system may lead to adverse pregnancy outcomes such as pre-eclampsia (PE). Hitherto, the potential of serum B7-1 and B7-H1 proteins as early markers of PE has not been explored in the Ghanaian population.

MATERIALS AND METHODS

This was a case-control study from May 2020 to April 2022 at the War Memorial and the Upper East Regional Hospitals. The study involved 291 women, including 180 (61.9%) with normotensive pregnancy and 111 (38.1%) with PE. Venous blood samples were collected and assayed for blood cell count, serum interleukins (ILs)-4, -6, -12, -18, and TNF-α as well as serum B7-1 and B7-H1 proteins.

RESULTS

The monocyte count (p = .007), the serum levels of IL-18 (p = .035), TNF-α (p = .001), and B7-H1 (p = .006) were significantly higher in PE than in normotensive pregnancy. In addition, the monocyte count (p = .002), the serum levels of IL-12 (p = .029), TNF-α (p = .016), and B7-1 (p = .009) levels were significantly higher in the third trimester than the second trimester PE. In predicting PE, the area under the curve of cytokines and ICMs ranged from 0.51 for IL-6 to 0.62 for TNF-α.

CONCLUSION

PE may be characterized by a dominant Th1-type immunity with higher levels of pro-inflammatory cytokines and B7-H1 proteins, but these variables may not be suitable for predicting PE.

Diet and Lifestyle Modifications for Fibromyalgia

Fibromyalgia (FM) is a complex, widespread pain disorder characterized by symptoms such as fatigue, sleep deprivation, mental fog, mood swings, and headaches. Currently, there are only three FDA-approved medications for FM patients: duloxetine, milnacipran, and pregabalin, with outcomes frequently being inadequate. This research team aims to investigate the effects of diet and lifestyle modifications on FM, with emphasis on anti-inflammatory diet, antioxidants, and gluten-free diets, as well as supplementation with Magnesium, CQ10, and Vitamin D, microbiome, sleep, exercise, and cognitive behavioral therapy. We reviewed the pathophysiology of certain foods that can be proinflammatory with the release of cytokines leading to activation of pain, fatigue and aggravation of the majority of Fibromyalgia symptoms. A literature review was performed by identifying FM articles published between 1994 and 2022 via PubMed and EMBASE databases, with particular emphasis on randomized controlled trials, meta-analysis, and evidence-based treatment guidelines. This review article was completed by a comprehensive narrative review process, in which our team systematically examined relevant scientific literature to provide a comprehensive overview of the significant role that diet and other lifestyle modifications play in mediating symptoms of Fibromyalgia. We propose that diet modifications and lifestyle changes, such as sleep, exercise, and weight loss, can be important steps in managing FM.

Animal protein intake is directly associated with serum level of pentraxin 3 in hemodialysis patients

Inflammation plays an important role in Cardiovascular disease (CVD) pathogenesis as the main cause of mortality in hemodialysis (HD) patients. Despite the relevance of nutrition and dietary intakes for inflammation status, the role of dietary protein sources remains unclear. The aim of this study was to evaluate the association between the different types of dietary protein and pentraxin 3 (PTX3) levels in HD patients. In this multi-center cross-sectional study, 227 adult patients undergoing HD for a minimum 90 days were recruited. A validated 168-item food frequency questionnaire was used to assess dietary intakes. Also, 5 ml blood samples were collected from each patient to measure the concentration of serum PTX3. Overall, 227 patients, including 63 women and 164 men, with a mean age of 58 years, participated in this study. There was a greater intake of animal protein per kilogram dry weight among patients with higher levels of PTX3 (0.46 vs. 0.54 g/kg; P = 0.035). In contrast, consumption of total protein and plant protein per kilogram dry weight was not different across PTX3 levels. Moreover, the chance of increased PTX3 concentration was directly associated with a one-unit increase in animal protein intake per kilogram dry weight, after adjusting for confounders. We did not observe any association between one-unit increases in plant protein intake per kilogram dry weight and chance of increased PTX3. In conclusion, animal protein intake was directly associated with circulating PTX3.

[Platelet-rich plasma (PRP) : Compositional analysis with different dietary habits and timing of blood sampling]

The variability of PRP is a major contributor to the lack of evidence regarding the therapeutic effect of PRP in musculoskeletal diseases. In a large study, we are currently investigating factors that may influence PRP variability. Interim results showed that concentrations of IL‑6, but not IGF‑1 or cellular constituents, were significantly decreased in PRP samples from vegans compared with omnivores and tended to be decreased compared to samples from vegetarians. This suggests that diet may have a significant influence on therapeutically active PRP constituents. However, the constituents studied here did not appear to be significantly affected by the timing of the sampling. Identification of significant variables affecting PRP composition will be critical to provide sufficient medical evidence for the therapeutic effects of PRP in orthopedic conditions.

Health benefits of legume seeds

Pulses have been part of human nutrition for centuries. They are also used in folk medicine as products with multidirectional medicinal effects. They are annual plants representing the Fabaceae family. Their edible part is the fruit, i.e. the so-called pods. Whole pods or their parts can be eaten, depending on the species and fruit ripeness. Beans, peas, peanuts, chickpeas, lentils, broad beans and soybeans are edible legume species. Legume seeds are characterized by high nutritional value. Compared to seeds from other plants, they have high protein content ranging, on average, from 20% to 35%, depending on the type, growing conditions and maturity of the fruit. This review focuses on various health-promoting properties of legumes and presents their nutritional value and compounds exerting health-promoting effects. Many pulses have a low glycemic index, which is important for prevention and treatment of diabetes. In addition to their low glycemic index and high fiber content, pulses have α-amylase and α-glucosidase inhibitors, which reduce the absorption of glucose from the gastrointestinal tract. These compounds have antidiabetic and anti-inflammatory effects. Pulses have been shown to contain bioactive peptides with angiotensin-converting enzyme inhibitory properties; hence, they are useful in the treatment of cardiovascular diseases. Pulses used in the nutrition of obese individuals provide compounds with pancreatic lipase inhibitory properties, thus promoting weight reduction and control. © 2023 Society of Chemical Industry.

A comprehensive review of healthy effects of vegetarian diets

AIMS

A comprehensive review comparing the effect of vegetarian (V) and non-vegetarian (NV) diets on the major cardiometabolic diseases' outcomes was performed.

DATA SYNTHESIS

We performed literature research (up to December 31, 2022) of the evidence separately for vascular disease (VD), obesity (OB), dyslipidemia (Dysl), hypertension (HPT), type 2 diabetes (T2D), metabolic syndrome (MetS), analyzing only cohort studies and randomized controlled studies (RCTs) and comparing the effect of V and NV diets. Cohort studies showed advantages of V diets compared to NV diets on incidence and/or mortality risk for ischemic heart disease, overweight and OB risk. Most cohort studies showed V had lower risk of HPT and lower blood pressure (BP) than NV and V diets had positive effects on T2D risk or plasma parameters. The few cohort studies on the risk of MetS reported mixed results. In RCTs, V diets, mainly low-fat-vegan ones, led to greater weight loss and improved glycemic control than NV diets and in the only one RCT a partial regression of coronary atherosclerosis. In most RCTs, V diets significantly reduced LDL-C levels (but also decreased HDL-C levels) and BP.

CONCLUSIONS

In this comprehensive review of the association between V diets and cardiometabolic outcomes, we found that following this type of diet may help to prevent most of these diseases. However, the non-uniformity of the studies, due to ethnic, cultural, and methodological differences, does not allow for generalizing the present results and drawing definitive conclusions. Further, well-designed studies are warranted to confirm the consistency of our conclusions.

Racing Experiences of Recreational Distance Runners following Omnivorous, Vegetarian, and Vegan Diets (Part B)-Results from the NURMI Study (Step 2)

The potential running or endurance performance difference based on following different general types of diets, such as omnivorous, vegetarian, or vegan, remains questionable. Several underlying modifiable factors of long-distance running performance, especially runner training behaviors and experience, diminish the clarity of results when analyzing dietary subgroups. Based on the cross-sectional design (survey), the NURMI Study Step 2 aimed to investigate a plethora of training behaviors among recreational long-distance running athletes and the relationship of general diet types with best time race performance. The statistical analysis was based on Chi-squared and Wilcoxon tests. The final sample (n = 245) included fit recreational long-distance runners following an omnivorous diet (n = 109), a vegetarian diet (n = 45), or a vegan diet (n = 91). Significant differences were found between the dietary subgroups in body mass index (p = 0.001), sex (p = 0.004), marital status (p = 0.029), and running-related motivations for well-being (p < 0.05) but not in age (p = 0.054). No significant difference was found for best time half-marathon, marathon, and/or ultra-marathon race performance based on diet type (p > 0.05). Whether the vegan diet is associated with enhanced endurance performance remains unclear. Although, the present results are suggestive that 100% plant-based (vegan) nutrition is compatible with distance running performance at the least.

Healthy dietary indices and noncancer pain: a systematic review of cross-sectional and longitudinal studies

ABSTRACT

Pain is a global public health problem given its high prevalence and incidence, long duration, and social and economic impact. There is growing interest in nutrition as potential modifiable risk factor related to pain; however, the associations between healthy dietary patterns and pain have not yet been well established. Thus, we aimed to systematically review and synthesise current cross-sectional and longitudinal evidence on the relationship between a priori healthy dietary patterns and noncancer pain among adults aged ≥18 years. We identified relevant published cross-sectional and longitudinal studies by systematically searching several electronic databases from inception to September 2021. Risk of bias was assessed using the modified Newcastle-Ottawa scale for cohort studies. A total of 14 cross-sectional and 6 longitudinal studies were included in the review. These studies measured different dietary scores/indices, such as different measures of adherence to the Mediterranean diet and the dietary inflammatory index. Pain ascertainment methods and pain measurements used differed across studies. All 20 of the included studies had different study designs and statistical analysis. Of these studies, 10 reported an inverse association between adherence to a healthy dietary pattern and pain, 5 reported mixed results, and 5 reported no associations. Despite notable heterogeneity, 50% of included observational studies reported that adherence to a healthy diet, particularly the Mediterranean diet, is inversely associated with pain. Of note, the cross-sectional design of most studies precludes any causal interpretation. Moreover, limited and inconsistent evidence from longitudinal studies highlights the need for further studies.

Assessment of Oxidant and Antioxidant Status in Prepubertal Children following Vegetarian and Omnivorous Diets

Oxidant-antioxidant balance is crucial for maintaining one’s health, and the diet is possibly one of the most important factors affecting this balance. Therefore, the aim of this study was to determine the oxidant-antioxidant balance in children on a lacto-ovo-vegetarian diet. The study was conducted between January 2020 and December 2021. The concentrations of total oxidant capacity (TOC), total antioxidant capacity (TAC), reduced (GSH), and oxidized (GSSG) glutathione, as well as C-reactive protein (CRP) and calprotectin were measured in serum samples of 72 healthy prepubertal children (32 vegetarians and 40 omnivores). The oxidative stress index (OSI) and the GSH/GSSG ratio (R-index) were calculated. Children on a vegetarian diet had significantly lower median values of TOC, GSH, and GSSG, and higher TAC compared with the omnivores. OSI was significantly lower in vegetarians, while R-index, as well as median values of CRP and calprotectin did not differ between both groups of children. Significant negative correlations were observed between TOC and TAC levels in the whole group of children and in vegetarians. GSH and GSSG levels correlated positively in the groups of vegetarians, omnivores, and in all the children. There were significant positive correlations between TOC and GSH, as well as GSSG levels in all the studied groups of children. Our study results suggest that the vegetarian model of nutrition allows to maintain the oxidant-antioxidant balance in the serum of prepubertal children.

Influence of the vegan, vegetarian and omnivore diet on the oral health status in adults: a systematic review and meta-analysis

OBJECTIVE

This systematic review aimed to evaluate the influence of the nature of diet (vegan, vegetarian, and omnivore) on the oral health status in adults.

METHODS

This systematic review and meta-analysis was performed using the PRISMA guidelines. Electronic databases [PubMed, Embase, CENTRAL], online search engines (Google Scholar), research portals, and hand searches were performed systematically to identify studies. The last literature search was performed February 1st, 2021. Studies were included if they reported on the influence of the nature of diet on the oral health status (oral hygiene, periodontal health, dental status, and salivary function) in adults, by two investigators. Inter-investigator reliability was evaluated using Kappa (κ) statistics. PROSPERO registration number: CRD42020211567.

RESULTS

Twenty-two studies were included for data extraction and final analysis. The meta-analysis revealed that the bleeding on probing measure was higher in omnivores (Z = -4.057, p < 0.0001; 95% CI: -0.684, -0.238; I² = 0.0%) and the overall periodontal health was significantly better in vegan/vegetarians than omnivores (Z = -2.632, p = 0.008; 95% CI: -0.274, -0.073; I² = 29.7%). Vegan/vegetarians demonstrated more dental erosion (Z = 3.325, p = 0.001; 95% CI: 0.170, 0.659; I² = 0.0%). In adults over 60 years old, the prevalence of caries was higher in omnivores (Z = 3.244, p = 0.001; 95% CI: 0.092, 0.371; I² = 0.0%), while complete edentulism was more prevalent in vegetarians (Z = -4.147, p < 0.0001; 95% CI: -0.550, -0.197; I² = 0.0%).

CONCLUSIONS

This review reveals that adults on an omnivore diet may be associated with a higher risk for periodontal problems and dental caries, while vegetarians/vegans may be associated with a higher risk for dental erosion.

A Vegetarian Diet Significantly Changes Plasma Kynurenine Concentrations

Tryptophan is an essential amino acid and a precursor of a number of physiologically important metabolites, including serotonin, melatonin, tryptamine, and kynurenines. We assessed tryptophan, kynurenines, and vitamin B2 and B6, as well as biomarkers of liver function and inflammation, in a group of 158 female omnivores and vegetarians aged 18-40 years. The majority of women were omnivores, and 22% were vegetarians. Vegetarians had 25% lower serum ALT, significantly higher pyridoxal concentrations, and significantly lower plasma concentrations of most kynurenines, varying from 8% lower concentrations of median plasma kynurenine to 42% lower concentrations of plasma xanthurenic acid, compared to omnivores. No significant differences were observed in vitamin B2 status or in inflammation markers, C-reactive protein and neopterin between the groups. Vegetarians had lower levels of several plasma kynurenines compared to omnivores. The reason for this is unknown; however, lower ALT concentrations, suggesting a better liver status, and a more favourable vitamin B6 status might be contributing factors.

Plant-Based Diets and the Incidence of Asthma Symptoms among Elderly Women, and the Mediating Role of Body Mass Index

We aimed to test the hypothesis that adherence to a healthful plant-based diet (hPDI) is associated with a subsequent decrease in the incidence of asthma symptoms, with an opposite association with adherence to an unhealthful plant-based diet (uPDI). In addition, we evaluated a potential mediating role of body mass index (BMI) and the modifying effect of smoking. Among 5700 elderly women from the French Asthma-E3N study with dietary data in 1993 and 2005, we assessed the incidence of asthma symptoms in 2018 among women with no asthma symptoms in 2011. BMI was evaluated in 2008. Mediation analyses in the counterfactual framework were used to disentangle total, direct, and indirect effects mediated by BMI. We found that both healthful and unhealthful plant-based diets were associated with a lower incidence of asthma symptoms over time, mediated by BMI (OR (95%CI) for the indirect effect: 0.94 (0.89-1.00) for hPDI and 0.92 (0.70-1.00) for uPDI)). Associations with both healthful and unhealthful PDIs were mediated by changes in BMI by 33% and 89%, respectively. Plant-based diets (healthful and unhealthful) were associated with subsequently reduced incidences of asthma symptoms over time, partly or almost totally mediated by BMI according to their nutritional quality.

Investigating the Effectiveness of Very Low-Calorie Diets and Low-Fat Vegan Diets on Weight and Glycemic Markers in Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Caloric restriction and vegan diets have demonstrated protective effects for diabetes, however their role in improving clinically relevant outcomes has not been summarized. Our aim was to evaluate the evidence for low-calorie diets (VLCD) and vegan diets on weight and glycemic control in the management of patients with Type 2 Diabetes. Database searches were conducted using Cochrane Library, MEDLINE (Ovid) and Embase. Systematic Review Registration: CRD42022310299. Methodological quality of studies was assessed using Cochrane RoB Tool for RCTs, Cochrane ROBINS-I RoB Tool for non-RCTs and NIH Quality Assessment tool for other studies. Sixteen studies with a total of 834 individuals were included and assessed to have a moderate to high risk of bias. Statistically significant changes in weight, BMI, and HbA1c were not observed in vegan diet cohorts. However, LDL cholesterol was significantly decreased by vegan diet. VLCDs significantly improved glycaemic control, with reductions in fasting glucose, pooled mean difference (MD) -1.51 mmol/L (95% CI -2.89, -0.13; p = 0.03; 2 studies) and HbA1c, pooled MD -0.66% (95% CI -1.28, -0.03; p = 0.04; 3 studies) compared to non-dietary therapy. Both diets suggested a trend towards improved weight loss and anthropometric markers vs. control. VLCD diet intervention is associated with improvement in glycaemia control in patients with Type 2 Diabetes.

Assessing the effects of alternative plant-based meats v. animal meats on biomarkers of inflammation: a secondary analysis of the SWAP-MEAT randomized crossover trial

Alternative plant-based meats have grown in popularity with consumers recently and researchers are examining the potential health effects, or risks, from consuming these products. Because there have been no studies to date that have specifically assessed the health effects of plant-based meats on biomarkers of inflammation, the purpose of this work was to conduct a secondary analysis of the Study With Appetizing Plantfood - Meat Eating Alternatives Trial (SWAP-MEAT). SWAP-MEAT was a randomised crossover trial that involved generally healthy adults eating 2 or more servings of plant-based meats per day for 8 weeks (i.e. Plant phase) followed by 2 or more servings of animal meats per day for 8 weeks (i.e. Animal phase). Results of linear mixed-effects models indicated only 4 out of 92 biomarkers reached statistical significance. The results were contrary to our hypothesis, since we expected relative improvements in biomarkers of inflammation from the plant-based meats.

Nutritional Biomarkers and Factors Correlated with Poor Sleep Status among Young Females: A Case-Control Study

Poor sleep status is associated with several health problems. Nutritional biomarkers and factors related to poor sleep are understudied. This study aimed to identify nutrition biomarkers and factors related to sleep status in healthy young Saudi females. The study included 92 normal-weight and obese Saudi females aged 19−25. Fasting blood glucose, insulin, and lipid profiles were measured. Insulin resistance was calculated on the basis of the homeostasis model assessment of insulin resistance (HOMA-IR) method. Anthropometric, stress, physical activity, and dietary data were collected. Data on the polyphenol content in foods were retrieved from the Phenol-Explorer database. The sleep status was assessed using the Pittsburgh sleep quality index (PSQI). Associations between variables were assessed using the multiple logistic regression model. Around 76% of the participants had poor sleep status (PSQI > 5). Multiple logistic regression reported high polyphenol intake as a protective factor against poor sleep (OR 0.24; 95% CI 0.07−0.83; p = 0.03) and HOMA-IR as an independent risk for poor sleep (OR 4.97; 95% CI 1.11−22.31; p = 0.04). Other nutritional biomarkers and factors, such as BMI, lipid profile, and vitamins, revealed a trend but were not significant. In conclusion, poor sleep status is associated with insulin resistance and low polyphenol intake among women of reproductive age.

The Effects of Eggs in a Plant-Based Diet on Oxidative Stress and Inflammation in Metabolic Syndrome

We recently reported that the inclusion of whole eggs in plant-based diets (PBD) increased plasma choline, lutein, and zeaxanthin in individuals with metabolic syndrome (MetS). The objective of the current study was to evaluate whether this dietary pattern would protect against oxidative stress and low-grade inflammation, two common characteristics of MetS. We recruited 24 men and women with MetS, who, after following a PBD for 2 weeks (baseline), were randomly allocated to consume either two whole eggs with 70 g of spinach/day (EGG) or the equivalent amount of egg substitute with spinach (SUB) as breakfast for 4 weeks. After a 3-week washout, they were allocated to the alternate breakfast. We measured biomarkers of oxidation and inflammation at baseline and at the end of each intervention. Tumor necrosis factor-alpha, interleukin-6, monocyte protein attractant-1, liver enzymes, and C-reactive protein, as well as total antioxidant capacity, paraoxonase-1 (PON-1) activity, and other biomarkers of oxidation were not different at the end of EGG or SUB or when compared to baseline. However, plasma malondialdehyde (MDA) concentrations were lower (p < 0.05) during the EGG and baseline compared to SUB. In addition, the increases in dietary lutein and zeaxanthin previously observed had a strong positive correlation with PON-1 activity (r = 0.522, p < 0.01) only during the EGG period, whereas plasma zeaxanthin was negatively correlated with MDA (r = −0.437, p < 0.01). The number of participants with MetS was reduced from 24 during screening to 21, 13, and 17 during the BL, EGG, and SUB periods, respectively, indicating that eggs were more effective in reversing the characteristics of MetS. These data suggest that adding eggs to a PBD does not detrimentally affect inflammation or oxidative stress; on the contrary, eggs seem to provide additional protection against the biomarkers that define MetS.

Effect of vegetarian diets on renal function in patients with chronic kidney disease under non-dialysis treatment: A scoping review

ABSTRACT Vegetable protein diets (VPDs) in chronic kidney disease (CKD) patients may be related to beneficial biological actions and possibly clinical impact. This is a scoping review that merge studies that evaluated the effect of a vegetarian diet on kidney function in adults with CKD under non-dialysis treatment. The evaluated outcome was the impact in renal function assessed by eGFR or creatinine clearance. MEDLINE (accessed by PubMed) was searched up to September 8, 2020. Data were extracted by two independent reviewers, who also assessed the quality of the studies. Of 341 retrieved articles, 4 studies assessing 324 patients were included in the analysis. One study showed that a very low-protein ketoanalogue-supplemented vegetarian diet had benefits in relation to a conventional low-protein diet, while the other three studies demonstrated no difference in kidney function between the evaluated diets. Additional studies are needed to assess the benefits of vegetarian diets for further recommendations in CKD management.

Association between Plant-Based Dietary Patterns and Risk of Cardiovascular Disease: A Systematic Review and Meta-Analysis of Prospective Cohort Studies

Plant-based diets, characterized by a higher consumption of plant foods and a lower consumption of animal foods, are associated with a favorable cardiovascular disease (CVD) risk, but evidence regarding the association between plant-based diets and CVD (including coronary heart disease (CHD) and stroke) incidence remain inconclusive. A literature search was conducted using the PubMed, EMBASE and Web of Science databases through December 2020 to identify prospective observational studies that examined the associations between plant-based diets and CVD incidence among adults. A systematic review and a meta-analysis using random effects models and dose–response analyses were performed. Ten studies describing nine unique cohorts were identified with a total of 698,707 participants (including 137,968 CVD, 41,162 CHD and 13,370 stroke events). Compared with the lowest adherence, the highest adherence to plant-based diets was associated with a lower risk of CVD (RR 0.84; 95% CI 0.79–0.89) and CHD (RR 0.88; 95% CI 0.81–0.94), but not of stroke (RR 0.87; 95% CI 0.73–1.03). Higher overall plant-based diet index (PDI) and healthful PDI scores were associated with a reduced CVD risk. These results support the claim that diets lower in animal foods and unhealthy plant foods, and higher in healthy plant foods are beneficial for CVD prevention. Protocol was published in PROSPERO (No. CRD42021223188).

Effect of dietary interventions on inflammatory biomarkers of inflammatory bowel diseases: A systematic review of clinical trials

OBJECTIVES

In this review, we systematically assess whether dietary interventions are effective in attenuating inflammatory biomarkers in IBDs based on clinical trials available in the literature.

RESEARCH METHODS & PROCEDURES

This review was conducted in accordance with the guidelines of the PRISMA. We used the PubMed and SciVerse Scopus databases and the Cochrane collaboration tool to assess the risk of bias in clinical trials. The PICO (patient, intervention, comparison, and outcomes) strategy was used, with the descriptors: "Inflammatory bowel disease", "Crohn's disease", "cd", "ibd", "ulcerative colitis", "uc", "Diet", "Diet Habits", "Feeding", "Nutrients", "Food Intake", "Dietary patterns", "Inflammations", "Inflammation", "acute-phase proteins", "C-reactive protein", "interleukins", "tumor necrosis factor-alpha" and "inflammatory response". There is no conflict of interest.

DATA ANALYSIS

Fifteen studies were included, with a total of 627 participants. Of the total studies included, seven showed a reduction in some inflammatory markers in response to dietary interventions. This review was registered with the PROSPERO platform under number: CRD42021235150.

CONCLUSIONS

The results presented in this review reveal that dietary intervention with specific characteristics may be important during the treatment of the inflammatory process in patients with IBDs.

The Association of Anti-Inflammatory Diet Ingredients and Lifestyle Exercise with Inflammaging

One of the latest theories on ageing focuses on immune response, and considers the activation of subclinical and chronic inflammation. The study was designed to explain whether anti-inflammatory diet and lifestyle exercise affect an inflammatory profile in the Polish elderly population. Sixty individuals (80.2 ± 7.9 years) were allocated to a low-grade inflammation (LGI n = 33) or high-grade inflammation (HGI n = 27) group, based on C-reactive protein concentration (<3 or ≥3 mg/L) as a conventional marker of systemic inflammation. Diet analysis focused on vitamins D, C, E, A, β-carotene, n-3 and n-6 PUFA using single 24-h dietary recall. LGI demonstrated a lower n-6/n-3 PUFA but higher vitamin D intake than HGI. Physical performance based on 6-min walk test (6MWT) classified the elderly as physically inactive, whereby LGI demonstrated a significantly higher gait speed (1.09 ± 0.26 m/s) than HGI (0.72 ± 0.28 m/s). Circulating interleukins IL-1β, IL-6, IL-13, TNFα and cfDNA demonstrated high concentrations in the elderly with low 6MWT, confirming an impairment of physical performance by persistent systemic inflammation. These findings reveal that increased intake of anti-inflammatory diet ingredients and physical activity sustained throughout life attenuate progression of inflammaging in the elderly and indicate potential therapeutic strategies to counteract pathophysiological effects of ageing.

Inflammatory, oxidative and DNA damage status in vegetarians: is the future of human diet green?

The health benefit of a vegetarian diet is still under debate as it may result in a higher intake of some beneficial micronutrients, while others may be reduced, thus influencing various metabolic pathways and health-related biomarkers. This scoping review discusses inflammatory, oxidative and DNA damage status in vegetarians and vegans compared to omnivores. Most of the reviewed studies indicated favorable effects of a vegetarian diet on oxidative status compared to omnivores but did not clearly associate particular dietary habits to genome damage. The evidence on the effect of vegetarian diet on the inflammatory and immunological biomarkers is poor, which could at least partly be explained by methodological constraints such as small sample size, short duration of vegetarianism and inconsistent definitions of the omnivorous diet. The only inflammatory biomarker that seems to be associated with the vegetarian diet was inflammatory mediator C-reactive protein, which in several studies showed lower values in vegetarians as compared to omnivores. There were very few studies on immunological markers and the results on the difference between vegetarians and omnivores were inconclusive. Although several biomarkers involved in oxidative stress and inflammation showed a beneficial association with the vegetarian diet, further research in well-defined and sufficiently sized cohorts is needed to provide more evidence.

Dietary Interventions with or without Omega-3 Supplementation for the Management of Rheumatoid Arthritis: A Systematic Review

Rheumatoid Arthritis (RA) is a chronic autoimmune condition characterized by symptoms of inflammation and pain in the joints. RA is estimated to have a worldwide prevalence of 0.5–1%, with a predominance in females. Diet may play an important role in the symptoms of RA; however, little is known about the effects of various diets. The aim of this systematic review is to explore the effect of dietary interventions, with or without omega-3 supplementation for the management of RA. The electronic databases MEDLINE, EMBASE, CINAHL, and the Cochrane Library were systematically searched for clinical trials investigating dietary interventions, with or without omega-3 supplementation to retrieve papers from inception to April 2021. Randomized and non-randomized controlled trials of dietary interventions in adults with RA were eligible for inclusion. Twenty studies with a total of 1063 participants were included. The most frequently reported outcomes were pain, duration of morning stiffness, joint tenderness, grip strength and inflammatory markers. Dietary interventions with an anti-inflammatory basis may be an effective way for adults with RA seeking complementary treatments, potentially leading to improvements in certain parameters. However, there is a need for longer duration studies that are well-designed and sufficiently powered to investigate the influence of diet on RA.

Effects of Dietary Patterns on Biomarkers of Inflammation and Immune Responses: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Altered immune cell phenotype and chronic inflammation are key features shared by various chronic diseases. Evidence from nutritional interventions aimed at alleviating inflammation could be a promising approach for the prevention of adverse health outcomes. We therefore aimed to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) to summarize the recent evidence on the effects of dietary patterns on inflammatory and immune-related biomarkers in humans. PubMed, Medline, and Web of Science databases were searched for publications up to October 2020. In total, 22 RCTs were included in the meta-analysis conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The Mediterranean diet appeared as the dietary pattern that showed the most prominent reductions of inflammatory biomarkers such as IL-6 [mean difference (MD): -1.07 pg/mL (95% CI: -1.94, -0.20); I2: 96%], IL-1β [MD: -0.46 pg/mL (95% CI: -0.66, -0.25); I2: 0%], and C-reactive protein [MD: -1.00 mg/L (95% CI: -2.02, 0.01); I2: 100%]. No substantial effects were observed for the additional dietary patterns studied in intervention research, including the Dietary Adherence to Stop Hypertension diet, and the vegetarian or vegan diets. Future large-scale multifactorial intervention studies are warranted to allow direct comparison of various dietary patterns in relation to a range of biomarkers reflecting multiple inflammatory and immune-related pathways.

Association of plant-based diet index with inflammatory markers and sleep quality in overweight and obese female adults: A cross-sectional study

BACKGROUND

Inflammation and sleep disturbances increase the risk of multiple diseases, including cardiovascular disease, type 2 diabetes and dementia. Since diet plays a significant role in inflammatory responses and sleep quality, this study aimed to investigate the association of a plant-based diet index (PDI) with sleep quality and inflammatory markers in overweight and obese women.

METHODS

390 overweight and obese women aged 18-48 years participated in this cross-sectional study. A validated food frequency questionnaire (FFQ) was used to create an overall PDI, healthful plant-based diet index (hPDI) and unhealthful plant-based diet index (uPDI). Sleep quality was assessed by Pittsburgh Sleep Quality Index (PSQI). Higher scores on the PSQI were indicative of poor sleep. Anthropometric measurements and serum concentrations of high-sensitivity C-reactive protein (hs-CRP), interleukin 1 beta (IL-1β) and transforming growth factor-beta (TGF-β) were evaluated. Linear regression models were used to determine the association between exposure and outcomes.

RESULTS

After taking potential confounders into account, we found a significant inverse association between adherence to hPDI and hs-CRP (β = -0.14, 95% confidence interval [CI]: -0.22,0.06, P = .001) and a significant positive association between uPDI and hs-CRP (β = 0.13, 95% CI: 0.05,0.21, P = .001). Overall, PDI was significantly associated with TGF-β (β = 2.04, 95% CI: 0.54,3.55, P = .008). No association was detected between PDI indices and IL-1β. Higher adherence to uPDI was significantly associated with higher PSQI score (lower sleep quality) (β= 0.20, 95% CI:0.007,0.40, P = .04). A significant positive association was found between TGF-β (β = 0.05, 95% CI:0.005,0.10, P = .03) and hs-CRP (β = 0.32, 95% CI:0.02,0.62, P = .03) with PSQI.

CONCLUSION

Our findings indicated a significant association between adherence to a plant-based diet with inflammation and sleep quality in obese and overweight females. WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?: Sleep is an essential part of life, and sleep quality has a significant impact on individual well-being and performance. There is a bidirectional relationship between disturbed sleep and elevated levels of inflammatory markers. Diet plays a major part in sleep quality and its related health consequences. Plant-based diets are associated with lower risk of chronic diseases such as coronary artery disease (CAD), type 2 diabetes, obesity and reduced level of inflammation. WHAT DOES THIS ARTICLE ADD?: Adherence to a healthful plant-based diet is associated with lower level of hs-CRP, while adherence to an unhealthful plant-based diet is associated with higher concentrations of hs-CRP. Adherence to an unhealthful plant-based diet is associated with lower sleep quality.

Vegetarian Dietary Patterns and Cognitive Function among Older Adults: The Adventist Health Study-2

We explored effects on cognitive function of following plant-based vegetarian compared with non-vegetarian dietary patterns in otherwise healthy older community-dwelling members of the Adventist Health Study-2 cohort (n = 132). Cognition was assessed using a comprehensive neuropsychological battery; a principal components analysis derived processing speed, executive function, and memory/language factors. Mild memory impairment (MMI) (n = 26, 19.7%) was identified by memory tests. Vegetarians consumed (a) meats, fish, and dairy <1 time/month, (b) dairy ≥1 time/month and meats, and fish <1 time/month, or (c) fish ≥1 time/month, no limits on dairy, and meats <1 time/month. Dietary patterns were determined at baseline, for each decade, and at cognitive assessment; a diet stability score was calculated. Factor scores were not different between vegetarians and non-vegetarians, nor was dietary pattern associated with a lower odds of MMI. A more stable diet over the life course was associated with better memory/language [β = 0.021 SE(β) = 0.008; p = 0.01]. This exploratory study did not support differences in processing speed, executive function, or memory/language abilities between vegetarians and non-vegetarians but did suggest that a more stable dietary pattern which was characteristic of vegetarians was associated with better memory/language abilities.

Managing Psoriatic Arthritis With a Whole Food Plant-Based Diet: A Case Study

A 40-year-old female teacher presented to the rheumatology clinic in 2003 with nonspecific back, knees, and right ankle pain. She was subsequently diagnosed with psoriatic arthritis and was taking methotrexate to control her disease. Over the years, her symptoms were mostly under control. However, in 2018, after adopting a whole food plant-based diet free of added salt, oil, and sugar, she was able to stop taking methotrexate. She was discharged from the rheumatology clinic and has remained symptom-free since. The available literature on managing psoriatic arthritis with diet shows that less than 2% of patients with psoriatic arthritis are able to discontinue medication as a result of disease remission. This case report adds to support and encourages further research in the field of managing inflammatory polyarthropathies with diet and lifestyle.

Vegetarian and Vegan Diet in Fibromyalgia: A Systematic Review

Fibromyalgia (FM) is a chronic non-degenerative disease characterized by the presence of multiple symptoms such as chronic pain, which negatively influence the quality of life of sufferers, most of whom are women. Currently, there is no effective treatment to limit the impact of these symptoms. The aim of this research is to review the scientific evidence on the effect of following a vegetarian or vegan diet on fibromyalgia patients. A systematic review included the original articles that answered the research question. These articles were in 2021 in the PubMed, Web of Science and Scopus databases. The research used the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. No time restriction was applied, and grey literature was not included. The evaluation of the methodological quality of the articles was carried out using the following different scales: STROBE (strengthening the reporting of observational studies in epidemiology), PEDro (Physiotherapy Evidence Database), and MMAT (Mixed Methods Appraisal Tool) scales. A total of 88 studies were analyzed, of which 6 investigations were included in this systematic review (n = 4 clinical trials and n = 2 cohort studies). These investigations show significant improvements in biochemical parameters, quality of life, quality of sleep, pain at rest and general health status when following mainly plant-based dietary patterns. In conclusion, these findings are promising but interpretation of the findings is limited due to the methodological quality of the studies. Well-designed clinical trials are needed to consolidate these dietary recommendations in FM patients.

The Influence of Nutrition on Adiponectin-A Narrative Review

The adipose tissue is an active endocrine organ which synthesizes and secretes a variety of adipokines, including adiponectin with its anti-inflammatory properties. Its expression is influenced by numerous factors such as age, sex, body weight and adipose tissue content. However, dietary factors, i.e., diet structure and the percentage of individual nutrients and products, are very important modulators. Beneficial dietary habits are the Mediterranean diet, DASH diet, diet based on plant products and diet with reduced energy value. Moreover, the share of individual products and nutrients which increase the concentration of adiponectin is worth noting. This group may include monounsaturated fatty acids, polyunsaturated omega-3 fatty acids, dietary fiber, polyphenols, alcohol and milk products. Conversely, dietary ingredients which have a negative effect on the concentration of adiponectin are typical components of the Western diet: saturated fatty acids, trans fatty acids, monosaccharides and disaccharides, and red meat. Furthermore, a diet characterized by a high glycemic index such as a high-carbohydrate low-fat diet also seems to be unfavorable. Due to the fact that available knowledge should be systematized, this study aimed to summarize the most recent research on the influence of dietary factors on the concentration of adiponectin.

Adherence to the vegetarian diet may increase the risk of depression: a systematic review and meta-analysis of observational studies

CONTEXT

Several epidemiological studies have investigated the association between a vegetarian diet and risk of depression, but because of inconsistency between studies, the exact association remains unclear.

OBJECTIVE

In this systematic review and meta-analysis, the relationship between vegetarian diets and risk of depression in observational studies was evaluated.

DATA SOURCES

The Medline, Embase, Scopus, ISI Web of Science, and Cochrane Library databases were searched from inception through September 1, 2020.

STUDY SELECTION

Observational studies were included that examined mean levels of depression and risk for depression in vegetarians compared with nonvegetarians.

DATA EXTRACTION

Pooled effect sizes were estimated using the random-effects model and were reported as standardized mean differences or odds ratios (ORs) with their corresponding 95%CIs. Heterogeneity was tested using the I2 statistic.

RESULTS

Combining 9 effect sizes in this meta-analysis illustrated that adherence to a vegetarian diet was associated with a 53% greater risk of depression compared with that of omnivores (95%CI, 1.14-2.07; I2 = 69.1%). Subgroup analysis of depression risk suggested that results depended on the type of vegetarian diet and country where the study was conducted. For studies that assessed a semivegetarian diet (OR, 1.86; 95%CI, 1.42-2.44; I2 = 35.7%) and those conducted in Europe and the United States (OR, 1.45; 95%CI, 1.06-1.98; I2 = 73.2%), there was a positive association between a vegetarian diet and depression, but in lacto-ovo vegetarians and Asian countries, a null association was found. Comparing mean depression scores showed no evidence of difference between vegetarians and nonvegetarians (n = 16; standardized mean difference, 0.10; 95%CI, -0.01 to 0.21; I2 = 79.1%).

CONCLUSION

Vegetarian diet significantly increased depression risk; however, the findings were not robust, and more studies are required to investigate the vegetarian diet and depression association.

Optimal Diet Strategies for Weight Loss and Weight Loss Maintenance

Obesity has become one of the most important public health problems worldwide, which suggests the need for evidence-based dietary strategies for weight loss and its maintenance. Weight management depends upon complex factors such as amount of food eaten, type of food eaten, and timing of meals. In this review, we identified evidence-based dietary strategies for weight management based on these three components. An energy deficit is the most important factor in weight loss. A low-calorie diet with a low fat or carbohydrate content has been recommended; however, in some cases, a very-low-calorie diet is required for a short period. Some macronutrient composition-based diets, such as the ketogenic diet or high-protein diet, could be considered in some cases, although the potential risks and long-term effectiveness remain unknown. Meal timing is also an important factor in weight management, and higher-calorie breakfasts in combination with overnight fasting may help to prevent obesity. Our review indicated that there is no single best strategy for weight management. Hence, strategies for weight loss and its maintenance should be individualized, and healthcare providers must choose the best strategy based on patient preferences.

Vegetarian diets, circulating miRNA expression and healthspan in subjects living in the Blue Zone

A long-term vegetarian diet plays a role in the longevity and maintenance of the healthspan, but the underlying mechanisms for these observations are largely unknown. Particularly, it is not known whether a long-term vegetarian dietary pattern may affect the circulating miRNA expression in such a way as to modulate the healthspan. The Adventist Health Study-2 (AHS-2) cohort includes a large number of older adults who primarily follow vegetarian dietary patterns and reside in Loma Linda, California, one of five “Blue Zones” in the world in which a higher proportion of the population enjoys a longer than average lifespan. We performed miRNA-seq in 96 subjects selected from the AHS-2 cohort with different dietary patterns. We identified several differentially expressed miRNAs between vegetarians and non-vegetarians, which are involved in immune response and cytokine signaling, cell growth and proliferation as well as age-related diseases such as cardiovascular diseases and neurodegenerative diseases. Overall, our study showed that a vegetarian diet modulates aging-associated circulating miRNAs in a sex-dependent manner of differential expression for certain miRNAs, which may be related in a beneficial manner to the healthspan. Further investigation is needed to validate these miRNAs as potential biomarkers for diet-modulated longevity in humans.

Systematic review and meta-analysis of the associations of vegan and vegetarian diets with inflammatory biomarkers

Plant-based diets like vegetarian or vegan diets might influence circulating levels of inflammatory biomarkers, thereby reducing the risk of chronic diseases. This systematic review and meta-analysis aimed to investigate the associations of veganism and vegetarianism with circulating inflammatory biomarkers in comparison to omnivores. Literature search was conducted in Pubmed and EMBASE until April 2020 and mean differences of biomarkers were assessed for: C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-18 (IL-18), interleukin-1 receptor antagonist (IL-1 RA), tumor necrosis factor-alpha (TNF-ɑ), E-selectin, intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1), adiponectin, omentin-1 and resistin. Of initially identified 1073 publications, 21 cross-sectional studies met the inclusion criteria and were included in the systematic review and meta-analysis. Vegan diet was associated with lower levels of CRP compared to omnivores [mean difference − 0.54 mg/l, 95%-CI: − 0.79 to − 0.28, p < 0.0001]. This association was less pronounced in vegetarians [mean difference − 0.25 mg/l, 95%-CI: − 0.49 to 0.00, p = 0.05]. In patients with impaired kidney function, the association between vegetarian nutrition and CRP was much stronger with − 3.91 mg/l (95%-CI: − 5.23 to − 2.60; p < 0.0001). No substantial effects were observed for all other inflammatory biomarkers. Despite strong associations between CRP and a vegan or vegetarian diet were seen, further research is needed, as most inflammatory biomarkers were investigated only in single studies so far.

The MIND (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay) and Mediterranean Diets are differently associated with psychosomatic complaints profile in adults: Results from SEPAHAN Cross-sectional study

BACKGROUND: In spite of an obvious association between diet and mental health, there is only few report regarding the association between diet and psychosomatic complaints. OBJECTIVE: To investigate the association of the Mediterranean-DASH diet intervention for neurodegenerative delay (MIND) diet with psychosomatic complaints profile in comparison with the Mediterranean diet (aMED). METHODS: In this cross-sectional study on 2818 Isfahanian adults, a validated dish-based food frequency questionnaire was used to assess dietary intakes. Psychosomatic complaints profile was evaluated through a self-administered Persian validated questionnaire by using exploratory factor analysis. RESULTS: After controlling for potential confounders, individuals in the highest quintile of the MIND diet had lower risk for experiencing psychological (odds ratio (OR)  = 0.60, 95% confidence interval (CI): 0.42, 0.86; P trend < 0.0001), and pharyngeal-respiratory (OR = 0.57, 95% CI: 0.41, 0.79; P = 0.002). The association for neuro-skeletal complaints was marginally significant (OR = 0.66, 95% CI: 0.43, 1.03; P = 0.093). The aMED diet tended to lower gastrointestinal complaints (OR = 0.68, 95% CI: 0.46, 1.01; P = 0.062). CONCLUSION: The MIND diet was inversely associated with different psychosomatic complaints risk, but no evidence of such an association for the MED diet was observed.

Dietary Interventions Are Beneficial for Patients with Chronic Pain: A Systematic Review with Meta-Analysis

Background

The standard Western diet is high in processed hyperpalatable foods that displace nutrient-dense whole foods, leading to inflammation and oxidative stress. There is limited research on how these adverse metabolic drivers may be associated with maladaptive neuroplasticity seen in chronic pain and whether this could be attenuated by a targeted nutritional approach. The aim of this study was to review the evidence for whole-food dietary interventions in chronic pain management.

Method

A structured search of eight databases was performed up to December 2019. Two independent reviewers screened studies and evaluated risk of bias by using the National Institutes of Health assessment tool for controlled or pre–post studies and the Joanna Briggs checklist for case reports. A meta-analysis was performed in Review Manager.

Results

Forty-three studies reporting on 48 chronic pain groups receiving a whole-food dietary intervention were identified. These included elimination protocols (n = 11), vegetarian/vegan diets (n = 11), single-food changes (n = 11), calorie/macronutrient restriction (n = 8), an omega-3 focus (n = 5), and Mediterranean diets (n = 2). A visual analog scale was the most commonly reported pain outcome measure, with 17 groups reporting a clinically objective improvement (a two-point or 33% reduction on the visual analog scale). Twenty-seven studies reported significant improvement on secondary metabolic measures. Twenty-five groups were included in a meta-analysis that showed a significant finding for the effect of diet on pain reduction when grouped by diet type or chronic pain type.

Conclusion

There is an overall positive effect of whole-food diets on pain, with no single diet standing out in effectiveness. This suggests that commonalities among approaches (e.g., diet quality, nutrient density, weight loss) may all be involved in modulating pain physiology. Further research linking how diet can modulate physiology related to pain (such as inflammation, oxidative stress, and nervous system excitability) is required.

Once-Daily Low Inflammatory Foods Everyday (LIFE) Smoothie or the Full LIFE Diet Lowers C-Reactive Protein and Raises Plasma Beta-Carotene in 7 Days

Serum C-reactive protein (CRP), a marker of systemic inflammation, is associated with increased risk for numerous inflammation-driven chronic diseases. A prior longitudinal study showed that the Low Inflammatory Foods Everyday (LIFE) diet, which is rich in dark green leafy vegetables (DGLV), lowered CRP over a mean follow-up period of 6 months. In this retrospective study, we investigate whether patients who consume the LIFE diet or their regular diet plus one component of the LIFE diet (LIFE smoothie), experience reductions in high-sensitivity CRP (hsCRP) in 7 days. Sixteen patients in a community practice met inclusion criteria. Patient compliance was assessed by patient interviews and measurements of beta-carotene, which is abundant in DGLV. Following the interventions, CRP decreased in both the LIFE diet (−0.47 mg/L, P = .02) and smoothie groups (−1.2 mg/L, P = .04). No statistically significant difference in reduction was observed between groups ( P = .18). Plasma beta-carotene increased in both groups (+23.2, P = .02; +20.6, P = .006, respectively). These findings suggest that the LIFE diet or a regular American diet supplemented with the LIFE smoothie may quickly reduce systemic inflammation and the risk of many chronic diseases.

Effects of a Vegetarian Diet on Cardiometabolic Risk Factors, Gut Microbiota, and Plasma Metabolome in Subjects With Ischemic Heart Disease: A Randomized, Crossover Study

Background A vegetarian diet (VD) may reduce future cardiovascular risk in patients with ischemic heart disease. Methods and Results A randomized crossover study was conducted in subjects with ischemic heart disease, assigned to 4-week intervention periods of isocaloric VD and meat diet (MD) with individually designed diet plans, separated by a 4-week washout period. The primary outcome was difference in oxidized low-density lipoprotein cholesterol (LDL-C) between diets. Secondary outcomes were differences in cardiometabolic risk factors, quality of life, gut microbiota, fecal short-chain and branched-chain fatty acids, and plasma metabolome. Of 150 eligible patients, 31 (21%) agreed to participate, and 27 (87%) participants completed the study. Mean oxidized LDL-C (-2.73 U/L), total cholesterol (-5.03 mg/dL), LDL-C (-3.87 mg/dL), and body weight (-0.67 kg) were significantly lower with the VD than with the MD. Differences between VD and MD were observed in the relative abundance of several microbe genera within the families Ruminococcaceae, Lachnospiraceae, and Akkermansiaceae. Plasma metabolites, including l-carnitine, acylcarnitine metabolites, and phospholipids, differed in subjects consuming VD and MD. The effect on oxidized LDL-C in response to the VD was associated with a baseline gut microbiota composition dominated by several genera of Ruminococcaceae. Conclusions The VD in conjunction with optimal medical therapy reduced levels of oxidized LDL-C, improved cardiometabolic risk factors, and altered the relative abundance of gut microbes and plasma metabolites in patients with ischemic heart disease. Our results suggest that composition of the gut microbiota at baseline may be related to the reduction of oxidized LDL-C observed with the VD. Registration URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT02942628.

Obese communities among the best predictors of COVID-19-related deaths

Coronavirus disease 2019 (COVID-19) is the largest outbreak to strike the world since the Spanish flu in 1918. Visual examination of the world map shows a wide variation of death tolls between countries. The main goal of our series is to determine the best predictors of such discrepancy.

METHODS

This is a retrospective study in which the rate of COVID-19 deaths was correlated with each of the following independent variables: total tests per 1 million population, gross domestic product (GDP), average temperatures per country, ultraviolet index, median age, average BMI per country, food supply, Bacille Calmette-Guerin compulsory status, and passenger traffic.

RESULTS

BMI per country proved to be the second best predictor of death rate with an R value of 0.43, and GDP being the best predictor with R = 0.65.

CONCLUSION

This article shows a tight correlation between average BMI, food supply per country, and COVID-19-related deaths. Such predisposing factors might operate by upregulating the inflammation pathway in heavily struck countries, leading to easier triggering of the infamous cytokine storm syndrome. Obesity also increases cardiovascular and respiratory morbidities, which are coupled to increased ICU demand and deaths among infected cases.Video abstract: http://links.lww.com/CAEN/A25.

How to protect both health and food system sustainability? A holistic 'global health'-based approach via the 3V rule proposal

OBJECTIVE

To define a generic diet to protect human health and food system sustainability based on three dimensions: animal:plant ratio, degree of food processing and food diversity.

DESIGN/SETTING

The percentages of maximum animal and ultra-processed energy content were evaluated from scientific papers (Web of Science database) and reports from international scientific institutions. Then, a weekly French standard diet, including these percentages and food diversity (≥42 different foods), was designed to calculate adequacy to nutritional needs.

RESULTS

Based on traditional and scientifically based healthy diets, and on foresight scenarios for sustainable diets at horizon 2050, a median daily animal energy content intake of 15 % was found to be protective towards both human health and environment. Based on epidemiological studies associating ultra-processed energy consumption with increased overweight/obesity risk, a precautionary threshold of approximately 15 % ultra-processed energy content was observed. The French diet allows addressing all nutritional needs and other nutritional indicators such as maximum salt and simple sugar consumption, α-linolenic acid:linoleic acid ratio and essential amino acids. This diet was named the '3V rule' for Végétal (plant), Vrai (real) and Varié (varied, if possible organic, local and seasonal). This generic diet can be adapted according to regional traditions and environmental characteristics. Excluding only one dimension of it would threaten both health and food system sustainability.

CONCLUSIONS

Tending towards a 3V-based diet, while respecting local constraints, should allow preserving human health, environment (greenhouse gas emissions, pollution, deforestation, etc.), small farmers, animal welfare and biodiversity, culinary traditions and socioeconomics (including an alleviation of public health cost).

Deep frying cooking oils promote the high risk of metastases in the breast-A critical review

Deep-frying is the most common food preparation method, manifestations of color, taste, flavor, and fried consistency. The beneficial role of vegetable oils become deteriorate when repeatedly treated with higher temperature and air. Repeatedly heated cooking oils (RCO) produce various byproducts, containing polycyclic aromatic hydrocarbons (PAHs) and aldehydes, well-known to be a carcinogenic, mutagenic, and tumorigenic properties. RCO is nowadays one of the often consumed media for cooking and frying, which intake can cause various unhealthy adverse effects including various cancer in the multiple organs. Hence, the present comprehensive study targets to provide the intake of RCO elevate the risks of human breast cancer. The data on RCO and its impacts were obtained via various electronic findings and library databases. Notable studies have confirmed that the effects of RCO have been attributed to their unfavorable effects, and underlying molecular mechanisms can also strongly promoting tumorigenic effects in the mammary organ.

Eating right for a healthier heart: Food choice contributes to cardiometabolic benefits and reduction of carotid intima-media thickness

OBJECTIVES

Diets may alter an individual's metabolism and inflammation, collectively leading to the modulation of cardiovascular health and disease process. The aim of this study was to investigate the effects of diets and diet-associated metabolites on metabolic profiles, inflammatory status, and severity of atherosclerosis.

METHODS

A cross-sectional study was conducted with 81 healthy adults in Taiwan. A food frequency questionnaire was obtained for evaluating dietary intake. Carotid intima-media thickness (CIMT), a relevant marker of subclinical atherosclerosis, was measured by ultrasound.

RESULTS

Consumption of instant noodles and sugary beverages was associated with worse metabolic profiles. In contrast, the intake of fresh fruit and green vegetables was correlated with better metabolic parameters. Sugary beverages were dose-dependently correlated with higher expressions of toll-like receptor (TLR)2 and TLR4 on monocytes, whereas fresh fruit intake was associated with lower TLRs. Furthermore, consumption of green vegetables, brown rice, and >2000 mL/d of water was inversely correlated with CIMT. The diet-associated metabolites including trimethylamine N-oxide and S-adenosyl-l-homocysteine, were positively associated with CIMT, whereas l-lysine and l-carnitine were associated with decreased CIMT. Interestingly, intake of strict vegetarian foods resulted in lower serum total cholesterol levels without a detectable effect on inflammatory status or CIMT.

CONCLUSIONS

Independent of the pattern of strict vegetarian foods, individuals who consumed more vegetables, fresh fruit, and water showed better cardiovascular health as evidenced by their metabolic and inflammatory status and CIMT results.

Association of Omnivorous and Vegetarian Diets With Antioxidant Defense Mechanisms in Men

Background Evidence that a vegetarian diet rich in antioxidants contributes to cardiovascular health are growing, however, the underlying molecular mechanisms remain unknown. HO-1 (heme-oxygenase-1), a marker of adaptive response, is protective against oxidative stress and has shown cardioprotective effects. Therefore, we evaluated circulating HO-1 levels and the effect of plasma from omnivorous and vegetarians in endothelial cells (human umbilical vein endothelial cells) on modulating NRF2 (nuclear factor erythroid 2-like 2)/HO-1 and nitric oxide production. Methods and Results From 745 participants initially recruited, 44 omnivorous and 44 vegetarian men matched by age and absence of cardiovascular risk factors and diseases were included in this study. Circulating HO-1 was measured using ELISA and human umbilical vein endothelial cells were incubated with plasma from omnivorous and vegetarians. Higher circulating HO-1 concentrations were found in omnivorous compared with vegetarians. Plasma from omnivorous and not from vegetarians induced NRF2/HO-1 and nitric oxide production in human umbilical vein endothelial cells, and increased reactive oxygen species production and caspase activity after incubation with stressor stimulus. Conclusions We suggest that HO-1 induction in omnivorous may indicate a pro-oxidative status since HO-1 is activated under oxidative stress a state not seen in vegetarians.