The beneficial consumption was 2+ cups a day, which translates to 200mg+ of caffeine a day, assuming caffeine is the substance with responsible for most of the beneficial effects of coffee on liver.
http://www.wiley.com/WileyCDA/PressRele ... 10553.html
"...Findings indicate that those who drank at least 20 g of ethanol daily had a greater risk of cirrhosis mortality compared to non-drinker. In contrast, coffee intake was associated with a lower risk of death from cirrhosis, specifically for non-viral hepatitis related cirrhosis. Non-alcoholic fatty liver disease (NAFLD), a chronic liver disease related to the metabolic syndrome and more sedentary affluent lifestyle, likely predominates among the non-viral hepatitis related cirrhosis group. In fact, subjects who drank two or more cups per day had a 66% reduction in mortality risk, compared to non-daily coffee drinkers."
http://www.wiley.com/WileyCDA/PressRele ... 10553.html
"...Findings indicate that those who drank at least 20 g of ethanol daily had a greater risk of cirrhosis mortality compared to non-drinker. In contrast, coffee intake was associated with a lower risk of death from cirrhosis, specifically for non-viral hepatitis related cirrhosis. Non-alcoholic fatty liver disease (NAFLD), a chronic liver disease related to the metabolic syndrome and more sedentary affluent lifestyle, likely predominates among the non-viral hepatitis related cirrhosis group. In fact, subjects who drank two or more cups per day had a 66% reduction in mortality risk, compared to non-daily coffee drinkers."