The Mediterranean diet increases glucagon-like peptide 1 and oxyntomodulin compared with a vegetarian diet in patients with type 2 diabetes: A randomized controlled cross-over trial

Rethinking weight loss treatments as cardiovascular medicine in obesity, a comprehensive review

The global escalation of obesity has made it a worldwide health concern, notably as a leading risk factor for cardiovascular disease (CVD). Extensive evidence corroborates its association with a range of cardiac complications, including coronary artery disease, heart failure, and heightened vulnerability to sudden cardiac events. Additionally, obesity contributes to the emergence of other cardiovascular risk factors including dyslipidaemia, type 2 diabetes, hypertension, and sleep disorders, further amplifying the predisposition to CVD. To adequately address CVD in patients with obesity, it is crucial to first understand the pathophysiology underlying this link. We herein explore these intricate mechanisms, including adipose tissue dysfunction, chronic inflammation, immune system dysregulation, and alterations in the gut microbiome.Recent guidelines from the European Society of Cardiology underscore the pivotal role of diagnosing and treating obesity to prevent CVD. However, the intricate relationship between obesity and CVD poses significant challenges in clinical practice: the presence of obesity can impede accurate CVD diagnosis while optimizing the effectiveness of pharmacological treatments or cardiac procedures requires meticulous adjustment, and it is crucial that cardiologists acknowledge the implications of excessive weight while striving to enhance outcomes for the vulnerable population affected by obesity. We, therefore, sought to overcome controversial aspects in the clinical management of heart disease in patients with overweight/obesity and present evidence on cardiometabolic outcomes associated with currently available weight management interventions, with the objective of equipping clinicians with an evidence-based approach to recognize and address CVD risks associated with obesity.

The role of plant-based dietary patterns in reducing COVID-19 risk and/or severity in adults: A systematic review and meta-analysis of observational studies

BACKGROUND & AIMS

Plant-based dietary patterns (PBDs) might protect against COVID-19 risk and reduce severity of infection. This systematic review with meta-analysis aimed to examine the association between PBDs and risk of COVID-19 infection, hospitalization, intensive care unit (ICU) admission, and/or mortality, in adults.

METHODS

Pubmed, Embase, CINAHL and Web of Science were searched for observational studies, published in English up to 3rd April 2023, comparing the highest with the lowest adherence to a specific PBD. Data were screened, extracted, and risk of bias assessed using the Newcastle-Ottawa Quality Assessment Scale, by independent reviewers.

RESULTS

Seven studies (one cross-sectional, three case-control, and three prospective cohort), reporting on 649,315 participants, were eligible. Across them, there were 8512 events of COVID-19 infection (six studies), and 206 events of COVID-19 hospitalization (four studies), in addition to one study reporting on a composite hospitalization outcome (740 events). The pooled analysis showed that PBDs are associated with a 59% (odds ratio (OR) = 0.41, 95% confidence intervals (CI) 0.23-0.59; two studies) and 18% (OR = 0.82, 95% CI 0.78-0.85; three studies) reduction in COVID-19 infection risk in case-control and cohort studies, respectively. The pooled analysis of one case-control and two cohort studies showed an inverse association between high adherence to a PBD and risk of COVID-19 hospitalization (OR = 0.38, 95% CI 0.04-0.72).

CONCLUSION

Findings suggest a protective role of PBDs against the risk of COVID-19 infection and severity. More studies are needed to establish the association between PBDs and risk of ICU admission and mortality due to COVID-19.

The effects of Mediterranean diet on cardiovascular risk factors, glycemic control and weight loss in patients with type 2 diabetes: a meta-analysis

To explore the impact of the Mediterranean diet on cardiovascular risk factors, glycemic control and weight loss in patients with type 2 diabetes(T2D) by a meta-analysis of randomized controlled trials (RCTs). We systematically searched PubMed, Cochrance Library, EMBASE and four Chinese databases to identify RCTs that compared the Mediterranean diet with control diets in patients with T2D up to December 2021. The Risk of Bias of the included studies was assessed using the version 2 of the Cochrane risk-of-bias tools for randomized trials (ROB 2). Seven RCTs with 1371 patients met the eligibility criteria and entered into the meta-analysis. Compared to control diets, the beneficial effects of Mediterranean diet were not statistically significant in high-density lipoprotein (MD = 2.33; 95% CI: -0.27 to 4.92), low-density lipoprotein (MD = -2.34; 95% CI -5.67 to 0.99) and total cholesterol (MD = 2.60; 95% CI: -0.95 to 6.15). But Mediterranean diet led to reduce the level of diastolic blood pressure (MD = -1.20; 95% CI: -2.21 to -0.19) and systolic blood pressure (MD = -4.17; 95% CI: -7.12 to -1.22). Meanwhile, Mediterranean diet showed beneficial effects in glycemic control (HbA1[%]: MD = -0.39, 95% CI: -0.58 to -0.20; fasting plasma glucose: MD = -15.12, 95% CI: -24.69 to -5.55) and weight loss (BMI: MD = -0.71, 95% CI: -1.30 to -0.78; WC: MD = -1.69; 95% CI: -3.35 to -0.02) compared to the control diets. The meta-analysis presented evidence supporting the beneficial effects of the Mediterranean diet on blood pressure, glycemic control, and weight loss. However, the impact of the Mediterranean diet on the lipid profile was not found to be significant, warranting further verification. This Meta-analysis was registered on the INPLASY website (Registration number: INPLASY 202160096).

Fermented foods: Harnessing their potential to modulate the microbiota-gut-brain axis for mental health

Over the past two decades, whole food supplementation strategies have been leveraged to target mental health. In addition, there has been increasing attention on the ability of gut microbes, so called psychobiotics, to positively impact behaviour though the microbiota-gut-brain axis. Fermented foods offer themselves as a combined whole food microbiota modulating intervention. Indeed, they contain potentially beneficial microbes, microbial metabolites and other bioactives, which are being harnessed to target the microbiota-gut-brain axis for positive benefits. This review highlights the diverse nature of fermented foods in terms of the raw materials used and type of fermentation employed, and summarises their potential to shape composition of the gut microbiota, the gut to brain communication pathways including the immune system and, ultimately, modulate the microbiota-gut-brain axis. Throughout, we identify knowledge gaps and challenges faced in designing human studies for investigating the mental health-promoting potential of individual fermented foods or components thereof. Importantly, we also suggest solutions that can advance understanding of the therapeutic merit of fermented foods to modulate the microbiota-gut-brain axis.

Dietary impact on fasting and stimulated GLP-1 secretion in different metabolic conditions - a narrative review

Glucagon-like peptide 1 (GLP-1), a gastrointestinal peptide and central mediator of glucose metabolism, is secreted by L cells in the intestine in response to food intake. Postprandial secretion of GLP-1 is triggered by nutrient-sensing via transporters and G-protein-coupled receptors (GPCRs). GLP-1 secretion may be lower in adults with obesity/overweight (OW) or type 2 diabetes mellitus (T2DM) than in those with normal glucose tolerance (NGT), but these findings are inconsistent. Because of the actions of GLP-1 on stimulating insulin secretion and promoting weight loss, GLP-1 and its analogs are used in pharmacologic preparations for the treatment of T2DM. However, physiologically stimulated GLP-1 secretion through the diet might be a preventive or synergistic method for improving glucose metabolism in individuals who are OW, or have impaired glucose tolerance (IGT) or T2DM. This narrative review focuses on fasting and postprandial GLP-1 secretion in individuals with different metabolic conditions and degrees of glucose intolerance. Further, the influence of relevant diet-related factors (e.g., specific diets, meal composition, and size, phytochemical content, and gut microbiome) that could affect fasting and postprandial GLP-1 secretion are discussed. Some studies showed diminished glucose- or meal-stimulated GLP-1 response in participants with T2DM, IGT, or OW compared with those with NGT, whereas other studies have reported an elevated or unchanged GLP-1 response in T2DM or IGT. Meal composition, especially the relationship between macronutrients and interventions targeting the microbiome can impact postprandial GLP-1 secretion, although it is not clear which macronutrients are strong stimulants of GLP-1. Moreover, glucose tolerance, antidiabetic treatment, grade of overweight/obesity, and sex were important factors influencing GLP-1 secretion. The results presented in this review highlight the potential of nutritional and physiologic stimulation of GLP-1 secretion. Further research on fasting and postprandial GLP-1 concentrations and the resulting metabolic consequences under different metabolic conditions is needed.

Dietary Fibre for the Prevention of Post-Pancreatitis Diabetes Mellitus: A Review of the Literature and Future Research Directions

Post-pancreatitis diabetes mellitus-the most common sequela of pancreatitis-leads to poorer glycaemic control compared with type 2 diabetes. Because post-pancreatitis diabetes mellitus is an exemplar of secondary diabetes (with a clear underlying cause), much post-pancreatitis diabetes mellitus is preventable or treatable early. Earlier literature established the important role of dietary fibre in reducing plasma glucose in individuals with type 2 diabetes. The present review benchmarks available evidence on the role of habitual dietary fibre intake in pancreatitis and post-pancreatitis diabetes mellitus. It also paves the way for future research on the use of dietary fibre in the post-pancreatitis setting.

Nutrition at the Intersection between Gut Microbiota Eubiosis and Effective Management of Type 2 Diabetes

Nutrition is one of the most influential environmental factors in both taxonomical shifts in gut microbiota as well as in the development of type 2 diabetes mellitus (T2DM). Emerging evidence has shown that the effects of nutrition on both these parameters is not mutually exclusive and that changes in gut microbiota and related metabolites such as short-chain fatty acids (SCFAs) and branched-chain amino acids (BCAAs) may influence systemic inflammation and signaling pathways that contribute to pathophysiological processes associated with T2DM. With this background, our review highlights the effects of macronutrients, carbohydrates, proteins, and lipids, as well as micronutrients, vitamins, and minerals, on T2DM, specifically through their alterations in gut microbiota and the metabolites they produce. Additionally, we describe the influences of common food groups, which incorporate varying combinations of these macronutrients and micronutrients, on both microbiota and metabolic parameters in the context of diabetes mellitus. Overall, nutrition is one of the first line modifiable therapies in the management of T2DM and a better understanding of the mechanisms by which gut microbiota influence its pathophysiology provides opportunities for optimizing dietary interventions.

The Influence of Ketone Bodies on Circadian Processes Regarding Appetite, Sleep and Hormone Release: A Systematic Review of the Literature

Chrononutrition is an emerging branch of chronobiology focusing on the profound interactions between biological rhythms and metabolism. This framework suggests that, just like all biological processes, even nutrition follows a circadian pattern. Recent findings elucidated the metabolic roles of circadian clocks in the regulation of both hormone release and the daily feeding–fasting cycle. Apart from serving as energy fuel, ketone bodies play pivotal roles as signaling mediators and drivers of gene transcription, promoting food anticipation and loss of appetite. Herein we provide a comprehensive review of the literature on the effects of the ketogenic diets on biological processes that follow circadian rhythms, among them appetite, sleep, and endocrine function.

An extra virgin olive oil-enriched chocolate spread positively modulates insulin-resistance markers compared with a palm oil-enriched one in healthy young adults: A double-blind, cross-over, randomised controlled trial

AIMS

To investigate if extra virgin olive oil (EVOO) or palm oil enriched chocolate spreads consumption leads to different results in terms of plasma ceramides concentration, glucose and lipid metabolism, inflammatory markers and appetite regulation in young healthy subjects.

METHODS

In a 2-week, double-blind, cross-over, randomised controlled trial, 20 healthy, normal-weight subjects with a mean age of 24.2 years (SD: 1.2), consumed chocolate spread snacks (73% of energy [%E] from fat, 20% from carbohydrates and 7% from proteins), providing 570 Kcal/day added to an isocaloric diet. The chocolate spreads were identical, except for the type of fat: EVOO oil, rich in monounsaturated fatty acids (MUFAs), or palm oil, rich in Saturated Fatty Acids (SFAs).

RESULTS

EVOO-enriched chocolate spread consumption led to better circulating sphingolipids and glucose profile, with reduced plasma ceramide C16:0, ceramide C16:0/ceramide C22:0-ceramide C24:0 ratio and sphingomyelin C18:0 (P = 0.030, P= 0.032 and P = 0.042, respectively) compared to the palm oil-enriched chocolate spread diet. HOMA-IR and plasma insulin were lower, while the Quicki and the McAuley Index were higher after the EVOO diet compared to the palm oil diet (P = 0.046, P = 0.045, P = 0.018 and P = 0.039 respectively). Subjects maintained a stable weight throughout the study. No major significant changes in total cholesterol, triglycerides, HDL, inflammatory markers, and appetite-regulating hormones/visual analogue scale were observed between the groups.

CONCLUSIONS

Partially replacing SFAs with MUFAs in a chocolate-based snack as part of a short-term isocaloric diet in healthy individuals may limit SFAs detrimental effects on insulin sensitivity and decrease circulating harmful sphingolipids in young adults.

Slow digestion-oriented dietary strategy to sustain the secretion of GLP-1 for improved glucose homeostasis

Dysregulated glucose metabolism is associated with many chronic diseases such as obesity and type 2 diabetes mellitus (T2DM), and strategies to restore and maintain glucose homeostasis are essential to health. The incretin hormone of glucagon-like peptide-1 (GLP-1) is known to play a critical role in regulating glucose homeostasis and dietary nutrients are the primary stimuli to the release of intestinal GLP-1. However, the GLP-1 producing enteroendocrine L-cells are mainly distributed in the distal region of the gastrointestinal tract where there are almost no nutrients to stimulate the secretion of GLP-1 under normal situations. Thus, a dietary strategy to sustain the release of GLP-1 was proposed, and the slow digestion property and dipeptidyl peptidase IV (DPP-IV) inhibitory activity of food components, approaches to reduce the rate of food digestion, and mechanisms to sustain the release of GLP-1 were reviewed. A slow digestion-oriented dietary approach through encapsulation of nutrients, incorporation of viscous dietary fibers, and enzyme inhibitors of phytochemicals in a designed whole food matrix will be implemented to efficiently reduce the digestion rate of food nutrients, potentiate their distal deposition and a sustained secretion of GLP-1, which will be beneficial to improved glucose homeostasis and health.

Controlled obesity status: a rarely used concept, but with particular importance in the COVID-19 pandemic and beyond

Obesity is a chronic disease that causes and aggravates several other diseases, and early reports suggest it is an important risk factor for COVID-19 severity. Although a deeper understanding of this relationship is vital, it is also important to inform the general public about the risks and, ideally, offer strategies to mitigate the risks. As "resolution" of obesity in the short-term is not feasible, it is indeed possible that smaller weight losses and increase in physical activity can actually reduce the risks. In this context, we propose that a term called "controlled obesity" be more often used and studied, in which those who have lost over 10% of their maximal weight and, ideally, are physically active are considered healthier. This context can have much broader usefulness, beyond the pandemics, as evidence points that weight loss over 10% can significant reduce overall health risks, irrespective of final BMI.