Dietary fiber (Cellulose and non-starch polysaccharides) (NSP)

Dietary cellulose and non-starch polysaccharides (NSPs) represent the primary constituents of dietary fiber, encompassing a diverse group of plant-derived carbohydrates that are resistant to digestion in the human small intestine (National Institutes of Health, 2023). Cellulose is a linear glucose polymer that provides structural integrity to plant cell walls, while NSPs such as pectins, hemicelluloses, and beta-glucans offer varying degrees of solubility and fermentability (British Nutrition Foundation, 2022). These compounds are essential for maintaining gastrointestinal health by increasing fecal mass and promoting regular peristalsis, thereby preventing constipation and diverticular disease (PubMed, PMID: 31296969). In the colon, they serve as substrates for fermentation by the gut microbiota, leading to the production of short-chain fatty acids (SCFAs) like butyrate, which are vital for colonocyte health and systemic metabolic regulation (World Health Organization, 2023). Clinically, high intake of these polysaccharides is associated with a reduced risk of chronic diseases, including type 2 diabetes, cardiovascular disease, and colorectal cancer. While not traditional molecular targets for small-molecule drugs, they are utilized as therapeutic bulk-forming laxatives and can significantly influence the pharmacokinetics of other medications by altering gastric emptying and intestinal transit time. Their physical properties, such as viscosity and water-holding capacity, are key determinants of their physiological effects and therapeutic utility in managing metabolic syndrome.

Other names

Dietary fiberNon-starch polysaccharidesCelluloseRoughagePlant fiberHemicellulosePectinBeta-glucan

Dietary cellulose and non-starch polysaccharides exert their effects through several physical and chemical mechanisms. They increase stool weight and decrease transit time by retaining water and providing physical bulk in the intestinal lumen (National Institutes of Health, 2023). Soluble NSPs form viscous gels that slow the absorption of glucose and lipids, thereby improving postprandial glycemic response and lowering LDL cholesterol by sequestering bile acids (PubMed, PMID: 24876314). Furthermore, their fermentation by colonic bacteria produces short-chain fatty acids (SCFAs), which act as signaling molecules that influence appetite regulation and inflammatory pathways (World Health Organization, 2023).