Abstract
Cassava fiber (CF) is a novel dietary fiber extracted from cassava by-products. To investigate its anti-obesity mechanism, obesity was induced in mice through a high-fat diet (HFD). Dietary supplementation with 10% CF significantly reduced body weight, body fat, triglycerides, low-density lipoprotein cholesterol, total cholesterol, and fasting blood glucose in mice. CF effectively ameliorated hepatic steatosis and adipocyte hypertrophy, increased the villus height-to-crypt depth ratio, enhanced mucus secretion by intestinal goblet cells, down-regulated the expression of ileal lipid absorption-related genes (NPC1L1, CD36, and FABP2), and up-regulated the short-chain fatty acid receptor GPR43, collectively improving intestinal health. Compared to HFD mice, CF altered the gut microbiota: it increased beneficial Actinobacteria (including Bifidobacterium and Blautia) and decreased Proteobacteria (including Desulfovibrio) (p < 0.05). Functional analysis showed that the HFD mice microbiota was enriched in genes linked to disease (e.g., lipid metabolism disorders, cancer, antibiotic resistance), whereas CF-enriched microbiota had genes for energy, carbohydrate, and pyruvate metabolism. Compared to microcrystalline cellulose, CF and MCC both alleviated HFD-induced obesity. In summary, cassava fiber helped prevent obesity in mice by modulating gut microbes, strengthening the gut barrier, and improving host metabolic balance.