Synergistic Effects of Fu Brick Tea Extract and Millet on Antiobesity in High-Fat Diet-Fed Mice through Gut Microbiota Modulation and Activation of the <i>Ffar2</i> – <i>Gcg</i> / <i>Pyy</i> Molecular Pathway

This study elucidates the antiobesity mechanism of the Fu brick tea extract-millet complex (FTE-M). FTE-M exhibited a dense and smooth microstructure, resulting in improved digestive properties compared with millet alone, including a reduced glycemic index and increased slowly digestible starch and resistant starch contents. In a 10-week high-fat diet mouse model, dietary supplementation with FTE-M inhibited small intestinal α-amylase activity, delayed starch digestion, and improved glucose and lipid metabolism while alleviating inflammation. FTE-M also modulated gut microbiota composition, normalized bile acid profiles, and enriched short-chain fatty acids (SCFAs)-producing bacteria, including <i>Akkermansia</i>, leading to a 2.49-fold increase in total SCFAs. Mechanistically, elevated SCFAs were associated with the activation of free fatty acid receptor 2 (<i>Ffar2</i>) and increased expression of glucagon (<i>Gcg</i>) and peptide YY (<i>Pyy</i>), contributing to enhanced satiety. These findings highlight the potential of combining traditional millet with bioactive components to enhance metabolic functionality, providing a theoretical basis for developing starch-based antiobesity foods.