Functional sweet tea in China: species, sweet components and anti-metabolic disease effects

Functional sweet tea refers to tea beverages with health benefits and sweetness made from natural sweet plants, which has shown a promising potential for the prevention and treatment of various chronic metabolic diseases. However, no comprehensive catalogs of sweet tea have been reported, and the systematic synthesis of their species, distribution, life forms, and health benefits is lacking. In this review, we firstly define scientific concept functional sweet tea, referred to tea beverages with health benefits and sweetness made from natural sweet plants. A total of 22 functional sweet tea plants in China and 27 reported functional sweet components is firstly compiled, which not only standardizes academic terminology but also directly facilitates market growth of the sweet tea industry. Sweet components show strong potential on preventing hyperglycaemia, hyperlipidaemia, hypertension, hyperuricaemia, liver disease through facilitation of glycolipid metabolism, anti-inflammatory and antioxidant pathways, targeting multiple key mediators such as AMPK, SGLT, Nrf2, and intestinal flora. This review provides new insights into the prevention and management of various metabolic diseases through sweet tea, and holds important theoretical and practical significance for the development of functional foods, the industrialization of natural sweeteners, and the optimization of prevention and management strategies for metabolic diseases.