Purpose of review <p>Black tea is one of the most widely consumed beverages globally and has been associated with several health-promoting effects due to its rich content of polyphenols, amino acids, and caffeine. This review aims to critically evaluate current evidence on the biological activities, health benefits, and major bioactive constituents of black tea, while also examining its emerging applications in cosmetic formulations and highlighting key research gaps requiring further investigation.</p> Recent Findings <p>Recent studies have demonstrated that the health-promoting effects of black tea are largely attributed to its polyphenols, caffeine, and amino acids, including theanine and gamma-aminobutyric acid. Current evidence suggests that regular black tea consumption may reduce the risk of non-communicable diseases, cardiovascular disorders, and neurodegenerative conditions through antioxidant, anti-inflammatory, and neuroprotective mechanisms, while also contributing to the prevention of dental caries and bone loss, promoting psychological well-being through relaxation and stress reduction, and demonstrating potential applications in cosmetic and skincare formulations owing to the antioxidant and protective properties of its bioactive compounds.</p> Summary <p>Black tea and its bioactive compounds, including polyphenols, amino acids, and caffeine, have been associated with a wide range of biological activities that may support human health and well-being. While black tea shows potential in therapeutic, nutraceutical, and cosmetic applications, further well-designed clinical trials and mechanistic molecular studies are required to validate these effects and elucidate the underlying mechanisms. Future research should focus on dose standardization, long-term safety, bioavailability, and the development of black tea–based functional foods and cosmetic products.</p>