The Impact of Matcha Green Tea on Human Health – Mechanisms of Action, Clinical Evidence, and Health Effects

Matcha green tea, a powdered whole-leaf preparation from shade-grown Camellia sinensis, exhibits a unique biochemical profile rich in catechins (particularly EGCG), L-theanine, caffeine, and chlorophyll, distinguishing it from conventional green teas. This narrative review synthesizes evidence on matcha's composition, mechanisms of action, and health effects. Mechanistically, EGCG activates the Nrf2/Keap1 antioxidant pathway, suppresses inflammatory signaling, and synergizes with L-theanine/caffeine to enhance cognitive function, while modulating gut microbiota toward beneficial taxa like Coprococcus. Clinical and preclinical studies demonstrate cardiometabolic benefits including improved glycemic control, lipid profiles, and hepatic protection against NAFLD, alongside cognitive enhancements and reduced exercise-induced fatigue. Preliminary data suggest anti-cancer potential via apoptosis induction and metabolic inhibition in tumor cells. Despite promising mechanistic insights, human trials remain limited by small samples, short durations, and heterogeneous preparations. Matcha emerges as a functional food with multifaceted health potential, warranting large-scale randomized controlled trials to establish optimal dosing, long-term efficacy, and safety for evidence-based recommendations.