The improvement effect of tea catechins on metabolic diseases: pharmacology and mechanism

Chronic metabolic diseases (CMDs), characterized by Type 2 diabetes mellitus (T2DM), obesity, and atherosclerosis, represent a global health crisis, significantly impairing patients' quality of life and imposing substantial socioeconomic burdens. Although current pharmacological interventions can mitigate disease progression, long-term administration carries the inherent risks of adverse effects. Medicinal food homologous (MFH) substances are emerging as promising interventions for metabolic disorders owing to their multitarget bioactivity, favorable safety profiles, and high patient compliance. Recent research demonstrates that tea catechins and their oxidative polymers exert beneficial effects against metabolic dysregulation through diverse mechanisms, including modulation of glucolipid metabolism, amelioration of insulin resistance, and anti-inflammatory actions. This review systematically synthesizes the molecular mechanisms and key signaling pathways underpinning the beneficial effects of tea catechins and their oxidative polymers in obesity, diabetes, and related syndromes, which include regulating glucolipid metabolism, improving insulin resistance, and exerting anti-inflammatory and antioxidant activities. Furthermore, the article critically discusses the clinical translational potential of these compounds, highlighting future applications as dietary supplements or adjuvant therapeutics. Collectively, these findings establish a theoretical foundation for developing novel natural product-based therapeutics against metabolic disorders.