Diet can affect health directly or by altering the gut microbiota; thus, there are strong interrelationships between the gut immune system, gut microbiota and diet. This study examined the effects of ingesting AIN-93M purified diet (PD) on gut immune function and gut microbiota in DO11·10 mice, in which T cell–dependent and T cell–independent (TI) IgA can be analysed separately. Ingestion of the PD for 2 weeks reduced both T cell–dependent and TI secretory IgA in the faeces compared with non-PD, whereas the diet did not affect T cell–dependent and TI serum IgA. Ingestion of the PD had no effect on systemic immune system splenocyte responses. Ingestion of the PD reduced intestinal tissue expression levels of B-cell activating factor and A proliferation–inducing ligand, cytokines involved in TI-IgA production and polymeric Ig receptor, which transports IgA into the intestinal lumen. Co-abundance group (CAG) analysis of the intestinal microbiota was conducted based on correlations between changes in the abundance of bacterial genera, and the correlations between CAG and IgA were determined. The Allobaculum-dominated CAG expanded following ingestion of the PD, accompanied by an inverse correlation with the decrease in faecal IgA, whereas the Lactobacillus-dominated CAG shrank relative to the Allobaculum-dominated CAG. These results suggest that TI-IgA suppresses the expansion of some intestinal bacteria and that ingestion of the PD induces dysbiosis via impaired IgA secretion into the intestinal lumen.

Obesity and depression are highly prevalent diseases that are strongly correlated. At the same time, there is a growing gap in care, and treatment options should be improved and extended. Positive effects of a Mediterranean diet on mental health have already been shown in various studies. In addition to the physiological effects of nutrients, the way food is eaten, such as mindful eating, seems to play a role. The present study investigates the effect of a Mediterranean diet and mindful eating on depression severity in people with clinically diagnosed major depressive disorder and obesity. Participants will be randomised to one of the four intervention groups (Mediterranean diet, mindful eating, their combination and a befriending control group). The factorial design allows investigating individual effects as well as potential synergistic effects of the interventions. The study consists of a 12-week intervention period, where five individual appointments will take place, followed by a 12-week follow-up. The primary outcome is depression severity. Secondary outcomes are remission of depression, assessor-rated depression severity, quality of life, self-efficacy, BMI, waist:hip ratio and body composition; adherence to the Mediterranean diet and mindful eating will also be assessed. Alongside mediator and moderator analysis, a microbiome analysis, a qualitative evaluation and an economic analysis will be conducted. The study investigates an important health issue in a vulnerable target group. It allows to draw valuable conclusions regarding the effectiveness of different interventions and therefore contributes to improving available care options for people suffering from depression and obesity.

Previous studies have shown that low-fat diet (LFD) is associated with various health benefits, and that lipid and fatty acid metabolism is linked to telomere shortening. However, no epidemiological studies have examined the association between LFD and telomere length (TL). Dietary information was collected using 24-h recalls among 6981 adults from a nationwide cross-sectional study. Diet quality was assessed using overall LFD, healthful LFD (hLFD) and unhealthful LFD (uLFD). TL was measured using quantitative PCR. Linear regression was employed to evaluate the association between LFD and log-transformed TL, and ordinal logistic regression was performed to assess the association of LFD with ordinal quintiles of TL in descending order. In both fully adjusted linear and ordinal regression models, higher overall LFD (Tertile 3 v. Tertile 1: percentage change = 2·48 %, 95 % CI: 0·60 %, 4·40 %, Ptrend = 0·003; OR = 0·79, 95 % CI: 0·68, 0·93; Ptrend = 0·001) and hLFD (Tertile 3 v. Tertile 1: percentage change = 2·71 %, 95 % CI: 0·87 %, 4·58 %; Ptrend = 0·002; OR = 0·84, 95 % CI: 0·72, 0·97; Ptrend = 0·003) scores were significantly associated with longer TL. The positive association between hLFD and TL was observed in other racial/ethnic groups, but not in non-Hispanic whites (Pinteraction < 0·005). There was no significant association between uLFD and TL in all the models. Our results suggest that LFD rich in high-quality carbohydrates, unsaturated fat and plant protein is associated with longer TL and underscore the need to consider the quality and dietary sources of the macronutrients.

Alpha-ketoglutarate (AKG) is a well-known intermediate of the tricarboxylic acid cycle and plays an important role in the catabolism of branched-chain amino acids (BCAAs: leucine, isoleucine, and valine). While previous study suggested that AKG enhances glucose metabolism, its effect on the adaptation of muscles and adipocytes has not been well studied in diabetic condition. This study aimed to determine whether AKG improves glucose metabolism in the skeletal muscles and adipose tissues in diabetic mice. Male institute of cancer research mice were divided into control, diabetic, and diabetic + AKG groups. Diabetes (DM) was induced by a high fat diet consumption and streptozotocin (STZ) injection. Mice in the DM + AKG group were administered 1% AKG in drinking water for 6 weeks. The non-fasting plasma glucose level was significantly higher in the diabetic group than that in the control and DM + AKG groups (P < 0.05). No significant difference was observed in glucose transporter 4 (GLUT4) protein levels in the muscles between the DM and DM + AKG groups. AKG supplementation attenuated the decrease in peroxisome proliferator-activated receptor γ coactivator 1 alpha and GLUT4 protein levels in inguinal and epididymal adipose tissues in diabetic condition. In conclusion, the study findings suggested that AKG supplementation increased protein levels related to mitochondrial biogenesis and glucose transporters in adipocyte tissue accompanied with improved whole-body glucose metabolism in STZ and high-fat diet-induced diabetic mice.

There is a gap in the understanding of meal patterns offered to students targeted by the National School Feeding Programme (PNAE). This study aimed to identify and analyse the menu patterns planned in schools participating in the PNAE. This observational cross-sectional study was carried out from a database consisting of 557 weekly menus from primary schools across Brazilian municipalities. We used factor analysis (FA) with principal components analysis (PCA) to identify menu patterns. Nutritional quality assessment of the menus was based on the Revised School Feeding Menu Quality Index (IQCAE-R). Differences in nutritional quality and associations with sociodemographic factors were analysed using the Kruskal–Wallis test, followed by Wilcoxon post hoc testing with Bonferroni correction. Two menu patterns were identified: (1) ‘Traditional’, predominantly composed of cereals and pasta, roots and tubers, legumes, vegetables, and meats and eggs; and (2) ‘Snack’, with a higher occurrence of bread, cakes, and biscuits, milk and dairy products, chocolate powder, and coffee and tea. The ‘Traditional’ pattern, consisting of food items commonly found in Brazilian food culture, and the ‘Snack’ pattern, characterised by the presence of sweets and highly processed foods, showed significant relationships with sociodemographic variables and nutritional quality of menus. Stimulating schools to provide meals that resemble the ‘Traditional’ pattern may contribute to the adoption of healthier dietary patterns, thus benefiting and strengthening health promotion through PNAE.

Promoting fruit and vegetable (F&V) consumption is a public health priority. This study assessed compliance with the international recommendation of consuming at least 400g of F&V daily among Mexican adults and analysed its association with the five stages of behaviour change from the Transtheoretical Model (Precontemplation, Contemplation, Preparation for action, Action, and Maintenance). Using data from 5203 adults (ages 20–59) in the 2016 National Health and Nutrition Survey, dietary intake was collected via a food frequency questionnaire. Compliance was defined dichotomously (Yes/No), and readiness to change was assessed using a specific survey module. Multiple logistic regression models examined the association between stages of change and compliance, adjusting for demographic, socioeconomic, and health characteristics, as well as perceived barriers and self-efficacy. Nationally, 26.3% of adults met the F&V recommendation. Compliance was significantly higher among individuals in the Preparation for action (OR 3.62, 95% CI: 1.82–7.19), Action (OR 4.50, 95% CI: 1.8–11.25), and Maintenance (OR 9.54, 95% CI: 4.76–19.13) than those in the Precontemplation stage. Higher compliance was also significantly associated with greater self-efficacy (OR 1.86, 95% CI: 1.4–2.47), being in the highest socioeconomic tertile (OR 1.71, 95% CI: 1.25–2.33), and living in the central region (OR 1.70, 95% CI: 1.18–2.45). Conversely, individuals reporting a dislike for vegetables were less likely to meet recommendations (OR 0.67, 95% CI: 0.48–0.94). These findings highlight the value of developing stage-tailored interventions that consider both psychological and structural barriers to improve F&V consumption.

This population-based cross-sectional study investigated the complex interplay of factors influencing high ultra-processed food (UPF) consumption among Brazilian adolescents using a hierarchical socio-ecological model. Data from 100 028 adolescents (13–17 years) enrolled in public and private schools nationwide were collected via self-administered questionnaires from the 2019 National School Health Survey. High UPF consumption was defined as ≥ 7 subgroups consumed on the previous day based on the NOVA classification. Poisson regression adjusted for complex sampling and hierarchical structure identified prevalence ratios (PR) for associated factors. High UPF consumption was significantly associated with younger age (PR = 1·22; 95 % CI 1·11, 1·34), regular breakfast consumption (PR = 1·32; 95 % CI 1·23, 1·42), regular screen time during meals (PR = 1·36; 95 % CI 1·27, 1·45), frequent UPF purchases at and around school (PR for canteen: 1·57; 95 % CI 1·43, 1·72; street vendors: 1·71; 95 % CI 1·55, 1·89), higher maternal education (PR 1·23, 95 % CI 1·12, 1·36) and lower parental supervision (PR 1·34, 95 % CI 1·11, 1·62). Living in the South (PR 1·50, 95 % CI 1·34, 1·69), Southeast (PR 1·30, 95 % CI 1·17, 1·44) and Midwest regions (PR 1·21, 95 % CI 1·09, 1·34) also correlated with higher consumption. Conversely, high body satisfaction and attending private school showed an inverse association. These findings underscore the intricate, multilevel influences on UPF consumption among Brazilian adolescents. Integrated interventions, spanning schools, family environments and public policies are crucial for promoting healthier eating habits and preventing obesity in this vulnerable population.