Abstract Coffee, a widely consumed beverage, has shown benefits for human health but lacks sufficient basic and clinical evidence to fully understand its impacts and mechanisms. Here, we conducted a cross‐sectional observational study of coffee consumption and a 1‐month clinical trial in humans. We found that coffee consumption significantly reshaped the immune system and metabolism, including reduced levels of inflammatory factors and a reduced frequency of senescent T cells. The frequency of senescent T cells and the levels of the senescence‐associated secretory phenotype were lower in both long‐term coffee consumers and new coffee consumers than in coffee nondrinking subjects, suggesting that coffee has anti‐immunosenescence effects. Moreover, coffee consumption downregulated the activities of the The Janus kinase/signal transduction and activator of transcription (JAK/STAT) and mitogen‐activated protein kinases (MAPK) signaling pathways and reduced systemic proinflammatory cytokine levels. Mechanistically, coffee‐associated metabolites, such as 1‐methylxanthine, 3‐methylxanthine, paraxanthine, and ceramide, reduced the frequency of senescent CD4+CD57+ T cells in vitro. Finally, in vivo, coffee intake alleviated inflammation and immunosenescence in imiquimod‐induced psoriasis‐like mice. Our results provide novel evidence of the anti‐inflammatory and anti‐immunosenescence effects of coffee, suggesting that coffee consumption could be considered a healthy habit.
