According to a long-standing myth (and it IS a myth), drinking lots of coffee can sober you up if you’re drunk. While coffee can’t bring you back to reality or fix a sick liver, it may protect the organ against damage.
Researchers at Southampton University (SU) in the UK conducted a meta-analysis of 9 studies covering data on 430,000 people. They found that people who drink 2 extra cups of coffee a day have a 44% decreased risk of developing liver cirrhosis, a condition associated with long-term heavy drinking that kills more than 1 million people worldwide each year. Liver cirrhosis can also be caused by hepatitis, immune disorders, and a buildup of fat in the liver, known as fatty liver disease.
“Cirrhosis is potentially fatal and there is no cure as such. It is significant that the risk of developing cirrhosis may be reduced by consumption of coffee, a cheap, ubiquitous and well-tolerated beverage. Coffee is a complex mixture containing hundreds of chemical compounds, and it is unknown which of these is responsible for protecting the liver.” 
Of the 430,000 individuals researchers looked at, 1,990 were diagnosed with cirrhosis. Daily coffee consumption was found to help reduce the risk of the condition in 8 out of 9 studies. One cup a day cut the risk of cirrhosis by 22%; 2 cups led to a 43% decreased risk; 3 cups a day lead to a 57% drop; and the maximum benefits came from consuming 4 cups a day, with a 65% decreased risk.
Filtered coffee seemed to offer greater benefits than boiled, though it’s not clear whether the difference was from the type of coffee beans used. In general, naturally occurring chemicals found in coffee are known to protect the liver. But once the liver becomes cirrhotic, there’s no way to fix it. 
A study published in 2013 in Clinical Gastroenterology and Hepatology found that daily coffee consumption cuts the overall risk of liver cancer by 40%. Drinking 3 cups of coffee a day was found to drop the risk by 50%.
This amazing nectar of the gods has also been credited with lowering the risk of a potentially deadly form of skin cancer called melanoma, and cutting the risk of Type 2 diabetes when 3-4 cups are consumed each day. Amazingly, drinking 4 or more cups of coffee has been shown to cut the recurrence and death rate of colon cancer by half.