Comparative effects of aged and newly produced white tea on glucose and lipid metabolism and the gut microbiota in mice with high-fat diet-induced obesity

With the global prevalence of obesity continuing to rise, white tea has attracted increasing attention as a potential dietary strategy for metabolic health. However, it remains unclear whether prolonged storage and the accompanying chemical transformations alter its metabolic benefits. To address above puzzle, high-fat diet (HFD)-fed mice were provided ad libitum with infusions of a 10-year-aged white tea (AWT) and newly produced white tea (NWT) for 4 weeks. Both teas ameliorated disturbances in glucose and lipid metabolism, accompanied by remodeling of the gut microbiota, attenuation of metabolic endotoxemia, and changes in the serum metabolites. Shared responses included reductions in lactate and glycerophospholipid-related metabolites, decreased Solibacillus abundance, and modulation of glycerophospholipid metabolism. However, the two teas showed distinct phenotypic effects. AWT exerted stronger hepatoprotective and lipid-protective effects, as indicated by reductions in serum aspartate aminotransferase (AST) and serum low-density lipoprotein cholesterol (LDL-C), whereas NWT produced greater reductions in body weight. These differences were associated with distinct chemical profiles: AWT rich in gallic acid (GA), caffeine, thearubigins (TRs), and theabrownin (TB), whereas NWT rich in levels of tea polyphenols, free amino acid, theobromine and catechins. Correlation analyses further associated AWT-enriched constituents with increased Lachnospiraceae_NK4A136_group abundance and serum azelaic acid, whereas NWT-associated bioactives correlated positively with betaine and NWT selectively enriched Akkermansia . Together, these findings indicate that storage-related chemical changes are associated with distinct metabolic effects of white tea while also revealing shared microbiota- and metabolite-related responses.