Many studies have suggested over the years that coffee may be able to protect the liver from serious ailments. Several have shown a protective effect against liver injury.
Among 5,944 adults in one study, who had liver injury from various causes (i.e. alcohol, hepatitis, iron overload, overweight, or blood sugar problems), increased coffee drinking was associated with lower incidence of liver enzyme abnormalities.
Another found that those who drank more than two cups of coffee a day had a 50% reduction in the risk of chronic liver disease.
In another large population study involving 125,580 individuals in a prepared health-care plan followed from 1978 through 1985, the risk of alcoholic cirrhosis in those who drank one cup, one to three cups, or four or more cups of coffee was 30%, 40% and 80%, respectively.
Moreover, coffee drinking also reduced the risk of death from cirrhosis as shown in these studies:
— In a U.S. study in which over 120,000 men and women were followed for eight years, the risk of death from alcoholic cirrhosis was reduced by 22% for each cup of coffee drunk per day.
— In a study conducted in Norway involving 51,000 men and women followed for 17 years, those who drank at least two cups of coffee a day had a 40% reduction of risk of death from cirrhosis as compared to those who had never drunk coffee.
There are several large population studies that show a positive protective effect of drinking coffee against liver cancer:
— In a meta-analysis with over 239,000 individuals, drinking two cups of coffee a day was associated with a 43% reduction in the risk of liver cancer.
— In a Finnish study involving over 60,000 adults, the risk of developing liver cancer in those who drank zero to one, two to three, four to five, six to seven or over eight cups of coffee daily were 100%, 66%, 44%, 38% and 32%, respectively.
— In a study involving over 18,000 individuals aged 40 to 69 years old, followed from 1993-94 to 2006, increased coffee was associated with a reduced risk of liver cancer depending on the number of cup(s) drank a day: less than one, one to two, and more than three, with risk reductions of 33%, 51%, 46% and 98%, respectively. These authors concluded that “coffee consumption may reduce the risk of liver cancer regardless of HCV and HBV infection status, whereas green tea may not reduce this risk.”
— In one study that tracked 90,000 adults for 10 years, increased intake of coffee per day was associated with a decrease in liver cancer. Drinking five cups or more of coffee a day led to a 76% reduced risk of liver cancer as compared to those who didn’t drink coffee. Those previously infected with hepatitis C had the best protection from drinking coffee.
— In another study that tracked 50,000 adults for up to nine years, the researchers only found a significant association between coffee drinking and liver cancer in those with a history of liver disease at the start of the study. The individuals who gave a history of liver disease at the start of the study and drank at least one cup of coffee a day had a 48% reduced risk for the development of liver cancer, as compared to those who did not drink any coffee.