Coffee doesn't just help out with hangovers, a U.K. study has found. It's even linked to a healthier liver.
Researchers combined the findings of nine previous studies on coffee and liver disease into one mass meta-analysis with data on more than 430,000 people. They found that drinking two extra cups of coffee per day is correlated with a 44 percent lower risk of liver cirrhosis, a chronic liver disease that kills more than one million people across the globe every year.
There is one large caveat to the report: all the studies involved were observational, not experimental. The study doesn't prove that coffee directly helps the liver — it's possible that coffee drinkers have a healthier lifestyle in general.
Also, not all of the studies took into account the same variables that affect liver health. For example, while all nine studies adjusted their results based on participants' reported alcohol consumption, "only six studies adjusted for age, six for body mass index and gender, and four for diabetes."
The report also noted that "people with pre-existing liver disease metabolise caffeine more slowly and, as a result, may drink less coffee."
However, researchers also pointed to previous animal experiments that suggest that caffeine has protective effects against liver damage. Some experiments have shown positive effects from even decaf coffee.
"Coffee contains a range of biologically active ingredients beyond caffeine, including anti-oxidative and anti-inflammatory agents," said the report.
Read the full study, published in Alimentary Pharmacology and Therapeutics, here.