Dietary Regulation of Intestinal Stem Cell Function: Nutrient-Sensing, Microbiota-Mediated, and Regenerative...

The intestinal epithelium is a dynamic tissue renewed by intestinal stem cells (ISCs) within the crypt niche. ISC behavior is regulated not only by intrinsic genetic programs but also by dietary composition, nutrient availability, microbial metabolites, and feeding rhythms. This narrative review synthesizes mechanisms through which diet influences ISC self-renewal, proliferation, differentiation, metabolic programming, and regenerative capacity. Dietary patterns exert context-dependent effects: caloric restriction, fasting, and structured feeding-fasting cycles may enhance epithelial regeneration through nutrient-sensing pathways, mitochondrial adaptation, and circadian regulation, whereas Western-type and high-fat diets may promote niche remodeling, inflammation, metabolic reprogramming, and tumorigenic risk. Macronutrients regulate ISC fate through carbohydrate metabolism, amino acid sensing, fatty acid oxidation, and lipid-derived signaling molecules. Micronutrients, including vitamins A, D, and B and minerals such as iron, zinc, selenium, and magnesium, contribute to epithelial differentiation, redox balance, and barrier integrity. Phytochemicals may modulate ISC function through Wnt/β-catenin, Nrf2, SIRT1, and epigenetic pathways or by stabilizing the epithelial microenvironment. The gut microbiota mediates diet-ISC interactions via short-chain fatty acids, bile acids, indole derivatives, and other metabolites. However, human evidence remains limited, and studies integrating human organoids, single-cell analyses, metabolomics, and chrononutrition are needed to inform personalized nutritional strategies for intestinal health.