Four consecutive weeks of dawn-to-dusk intermittent fasting are associated with improved markers of gut barrier integrity and attenuated subclinical intestinal inflammation in adults with overweight and obesity: a prospective cohort study

Inflammatory bowel diseases (IBD) are among the most prevalent immune-mediated inflammatory diseases, with an alarmingly growing prevalence worldwide. Intermittent fasting (IF) regimens are increasingly considered among the non-pharmacological, safe preventive and dietary modification measures against IBD pathways. The current study examined changes in anthropometric, metabolic, inflammatory, and molecular biomarkers related to gut barrier integrity and systemic inflammation in non-IBD individuals with overweight/obesity, following four weeks of dawn-to-sunset Ramadan IF (RIF). A total of 46 participants (34 males and 12 females, 37.9 ± 10.5 years) with overweight/obesity (29.9 ± 4.9 kg/m2) were enrolled. Anthropometric, metabolic, inflammatory, and molecular IBD-related markers, as well as dietary intakes, were assessed 1 week before and during the fourth week of Ramadan. Observing RIF was associated with significantly ( p < 0.01) reduced serum inflammatory markers (IL-6, TNF-α, NF- κ B, serum calprotectin) and increased anti-inflammatory IL-10, while also elevating antioxidant markers (Nrf2, PGC-1α). Body weight, BMI, fat mass, and body fat per cent, along with waist and hip circumferences, significantly decreased ( p < 0.05). At the same time, HDL cholesterol levels increased significantly ( p < 0.01) at the end of Ramadan compared with pre-fasting levels. Significant increases in total sugar intake ( p < 0.001), polyunsaturated fatty acids ( p = 0.034), and omega-3 fatty acids ( p = 0.001) were reported during Ramadan when compared to the pre-fasting levels. Conversely, there was a significant decrease in protein intake ( p = 0.006) and cholesterol intake ( p = 0.004). Observing four weeks of dawn-to-dusk RIF is associated with significant, favorable changes in circulating and molecular biomarkers linked to gut barrier integrity and systemic inflammation in non-IBD individuals with overweight/obesity. These findings suggest a possible improvement in the subclinical inflammatory profile and systemic endotoxemic stress, highlighting the potential of time-restricted eating rhythms to support metabolic and intestinal homeostasis, with promising preventive implications against IBD development in at-risk individuals.