The very-low-calorie ketogenic diet (VLCKD) is effective and safe for obese individuals, but limited information exists on its impact on the intestinal barrier. This study analyzed the effects of 8 weeks of VLCKD on 24 obese patients (11M/13F). Carbohydrate intake was fixed at 20–50 g/day, while protein and lipid intake varied from 1–1.4 g/kg of ideal body weight and 15–30 g per day, respectively. Daily calorie intake was below 800 kcal. The lactulose–mannitol absorption test assessed small intestinal permeability. Multiple markers, such as serum and fecal zonulin, fatty acid-binding protein, diamine oxidase concentrations, urinary dysbiosis markers (indican and skatole), and circulating lipopolysaccharide levels, were analyzed. Inflammation markers (serum interleukin 6, 8, 10, and tumor necrosis factor-α concentrations) were also evaluated. The results showed significant reductions in weight, BMI, and waist circumference post-diet. However, the lactulose–mannitol ratio increased by 76.5%, and a significant increase in dysbiosis markers at the end of the diet occurred. This trend was particularly evident in a subgroup of patients. Despite initial benefits, the VLCKD might negatively affect the intestinal barrier function in obese patients, potentially worsening their compromised intestinal balance.

The dietary approach low in oligosaccharides, disaccharides, monosaccharides, and fermentable polyols (FODMAPs-LFD) is a good strategy for treating irritable bowel syndrome (IBS). Beyond the LFD, other dietary approaches with beneficial effects may be hypothesized. Among them, consumption of Tritordeum-based foods (TBD, bread, bakery products, and pasta) in substitution of other cereals seem to achieve promising results. In a randomized controlled trial, we compared the effects of 12 weeks of LFD to TBD in improving the symptom profile of IBS-diarrhea (IBS-D) patients. The two diets equally improved gastrointestinal symptoms and QoL, measured by the IBS Severity Scoring System (IBS-SSS) questionnaire, reducing the total score after four weeks and maintaining this range until the end of treatment (IBS-SSS total score change: −132.1; 95% CI: −74.9 to −189.4 and −130.5; 95% CI: −73.2 to −187.7; p < 0.0001 after LFD and TBD, respectively). The two diets did not modify the micronutrients content when extended for 12 weeks. LFD could be regarded as a first-line dietary approach for IBS-D patients. However, TBD may represent a valid alternative, with high palatability, especially among Italian patients, for whom pasta is considered one of the main assets of dietetic culture, and would be easier to manage in their daily habits.

Walking is popular moderate-intensity aerobic exercise that improves mental and gastrointestinal (GI) health. It can relieve symptoms associated with irritable bowel syndrome (IBS), e.g., intestinal gas, abdominal distension, and bowel disturbances. This study examined the impact of a moderate-intensity aerobic exercise program on the clinical and psychological parameters of IBS patients. In total, 40 IBS patients (11 males and 29 females; mean age 51.9 ± 7.8 years) participated in a 12-week aerobic exercise program. Participants completed questionnaires assessing GI symptoms, psychological profiles, and quality of life (QoL) before and after the intervention. Field tests, anthropometric measurements, and bioimpedance assessments were also conducted. The present findings confirmed a significant improvement in IBS symptoms after the aerobic exercise program. Bloating was the most common symptom and, together with abdominal pain, was significantly reduced after treatment. Psychological and QoL questionnaires indicated decreased anxiety, depression, somatization, and stress levels. Correlations were found between anxiety/depression and the severity of abdominal pain as well as between stress and the severity of abdominal distension. Moderate-intensity aerobic exercise positively impacted GI symptoms and psychological well-being, complementing dietary and psychological support as a non-pharmacological therapy for the management of IBS. These findings emphasize the importance of alternative approaches for IBS treatment.

Aims: This study explores the link between body mass index (BMI), intestinal permeability, and associated changes in anthropometric and impedance parameters, lipid profiles, inflammatory markers, fecal metabolites, and gut microbiota taxa composition in participants having excessive body mass. Methods: A cohort of 58 obese individuals with comparable diet, age, and height was divided into three groups based on a priori clustering analyses that fit with BMI class ranges: Group I (25–29.9), Group II (30–39.9), and Group III (>40). Anthropometric and clinical parameters were assessed, including plasma C-reactive protein and cytokine profiles as inflammation markers. Intestinal permeability was measured using a multisaccharide assay, with fecal/serum zonulin and serum claudin-5 and claudin-15 levels. Fecal microbiota composition and metabolomic profiles were analyzed using a phylogenetic microarray and GC-MS techniques. Results: The statistical analyses of the clinical parameters were based on the full sample set, whereas a subset composed of 37 randomized patients was inspected for the GC/MS metabolite profiling of fecal specimens. An increase in potentially pro-inflammatory bacterial genera (e.g., Slackia, Dorea, Granulicatella) and a reduction in beneficial genera (e.g., Adlercreutzia, Clostridia UCG-014, Roseburia) were measured. The gas chromatography/mass spectrometry analysis of urine samples evidenced a statistically significant increase in m-cymen-8-ol, 1,3,5-Undecatriene, (E, Z) and a decreased concentration of p-cresol, carvone, p-cresol, and nonane. Conclusions: Together, these data demonstrated how an increased BMI led to significant changes in inflammatory markers, intestinal barrier metabolites, glucose metabolism, endocrine indicators, and fecal metabolomic profiles that can indicate a different metabolite production from gut microbiota. Our findings suggest that targeting intestinal permeability may offer a therapeutic approach to prevent and manage obesity and related metabolic complications, reinforcing the link between gut barrier function and obesity.

Moderate-intensity aerobic exercise improves gastrointestinal (GI) health and alleviates irritable bowel syndrome (IBS) symptoms. This study explored its effects on physical capacity (PC) and IBS symptoms in 40 patients from Southern Italy (11 males, 29 females; 52.10 ± 7.72 years). The exercise program involved moderate-intensity aerobic exercise (60/75% of HRmax) for at least 180 min per week. Before and after the intervention, participants completed the IBS-SSS questionnaire to assess IBS symptoms, reported their physical activity levels, and underwent field tests to evaluate PC. PC was quantified as the Global Physical Capacity Score (GPCS). A total of 38 subjects (21 males, 17 females; 53.71 ± 7.27 years) without lower GI symptoms served as a No IBS group. No significant differences were found between IBS patients and No IBS subjects, except for the symptom score, as expected. After the exercise, all participants experienced significant improvements in both IBS symptoms and PC. Higher PC levels correlated with greater benefits in IBS symptomatology, especially with GPCS reaching above-average values. Engaging in moderate-intensity aerobic exercise for at least 180 min per week positively impacts IBS symptoms and PC. Monitoring GPCS in IBS patients provides insights into the connection between physical activity and symptom severity, aiding healthcare professionals in tailoring effective treatment plans.

Since irritable bowel syndrome (IBS)—a common gastrointestinal (GI) disorder—still lacks effective therapy, a nutritional approach may represent a practical alternative. Different reports demonstrated that a low-fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) diet (LFD) reduces symptoms in IBS with diarrhea (IBS-D) patients, also inducing beneficial pathophysiological and biochemical modifications. More recently, diets with alternative cereals having a different gluten composition, such as tritordeum, have also been considered (TBD). We investigated the impact of TBD and LFD on the fecal metabolome composition in 38 IBS-D patients randomly allocated to the two diets for 12 weeks. Summarily, at baseline, the profile of fecal volatile organic compounds (VOCs) of IBS-D patients was not significantly different in the two groups. After treatment, significant changes were observed in the two groups regarding the VOCs content since some of them increased in the TBD group (namely, decanoic acid), whereas others (i.e., nonanal and ethanol) increased in the LFD one. Further, at baseline, short-chain fatty acids were positively related to inflammation and showed a significant decreasing trend after both diets compared to baseline values (namely, acetic and propanoic acid). Preliminary results from this pilot study suggest a potential positive intervention of TBD and LFD affecting the fecal metabolome composition in IBS-D patients.