A large new study has found that regular coffee drinking is associated with a significantly lower risk of severe liver disease, liver cancer and liver-related death. Published in the journal Clinical Gastroenterology and Hepatology, the research drew on data from 354,957 participants in the UK Biobank who had no history of cirrhosis or liver cancer at the outset and were followed for an average of 13 years. The findings matter because, unlike earlier work that noted a statistical link, this study also offers biological evidence to help explain why coffee may protect the liver.

The protective effect appeared to strengthen with higher consumption. Those drinking one to two cups a day had a 20% lower risk of developing cirrhosis and a 31% lower risk of liver-related death, while people drinking five or more cups daily saw a 32% reduction in cirrhosis risk, a 42% lower risk of liver-related death and a 47% lower risk of hepatocellular carcinoma, the most common primary liver cancer. Imaging data from nearly 29,000 participants and blood samples from around 50,000 showed heavy coffee drinkers had lower liver fat and iron, less fibroinflammation, and more favourable levels of inflammation- and scarring-related proteins. Notably, the benefits were similar for caffeinated and decaffeinated coffee, suggesting they stem from naturally occurring compounds other than caffeine.