The study examined nearly 6,000 people who were considered to be at high risk for developing liver disease from excessive drinking, hepatitis, obesity or other factors known to effect the liver's functioning. During the course of the study, the subjects reported how much coffee, tea or caffeinated soft drinks they consumed.
Those who drank larger quantities of caffinated drinks were less likely to develop liver disease. The mechanism for this protection is not known at this time, though it is speculated that the caffeine blocks a receptor in the liver and may have protective properties. Further studies are planned.