Coffee's effects on immune system and autoimmune disease risk

Coffee is one of the world’s most widely consumed beverages, and recent scientific interest has turned to its influence on the immune system and autoimmune diseases. Caffeine, a methylxanthine, blocks adenosine receptors that regulate inflammation and immune‑cell activity, affecting T‑lymphocytes, cytokine production, macrophage function and overall inflammatory responses. Dr. Eleni Komninou notes, “The coffee‑immune relationship is much more complex than previously thought.” In moderate amounts caffeine appears to have anti‑inflammatory properties, while excessive intake may produce different effects depending on genetics and individual health.

Coffee also contains thousands of bioactive compounds—chlorogenic acids, polyphenols, diterpenes and antioxidants—that can lower oxidative stress and modulate inflammatory pathways. Earlier studies linked high coffee consumption to a greater risk of rheumatoid arthritis, but newer analyses do not confirm a significant increase; moderate consumption is not shown to raise risk. Similar nuanced findings apply to systemic lupus erythematosus and other autoimmune conditions, with outcomes likely shaped by genetic, environmental and metabolic factors.