NEW YORK (Reuters Health) - A few cups of coffee everyday may help slow the progression of liver disease associated with long-term infection with the hepatitis C virus, a new study hints.
Researchers found that among 766 patients with hepatitis C-related liver damage, those who drank three or more cups of coffee per day were 53 percent less likely than non-drinkers to see their liver disease progress over four years.
The findings, published in the journal Hepatology, do not prove that coffee, per se, protects the liver from hepatitis C damage. So it is too soon for people with long-term, also known as chronic, hepatitis C infection to boost their coffee intake.
“Though our results are intriguing, we need future studies to confirm our results before any recommendations in regards to coffee drinking can be made,” lead researcher Dr. Neal D. Freedman, of the U.S. National Cancer Institute, told Reuters Health in an email.
Still, the results are in line with past research showing that coffee drinkers have lower risks of developing other liver diseases, including liver cancer.
Hepatitis C is a viral infection usually passed through contact with infected blood — most often by sharing tainted needles — though a small number of cases are sexually transmitted or passed from mother to baby during childbirth.
In a minority of people, the body is able to clear the virus soon after infection. However, the infection becomes long-term about 85 percent of the time, often leading to liver damage like chronic inflammation, scarring of the liver tissue (cirrhosis) and, in some cases, liver cancer.
For the current study, Freedman and his colleagues followed 766 patients with hepatitis C-related liver scarring. All had been treated with the anti-viral drugs peginterferon and ribavirin, the standard therapy for chronic hepatitis C, but the drugs had failed to clear the virus from their bodies.
Over 3.5 years, 230 patients showed progression in their disease, such as increased scarring, brain or nervous system damage related to their liver disease, or liver cancer.
Freedman’s team found that the risk of progression declined as patients’ coffee intake rose. Compared with those who were non-drinkers at the outset, patients who had one to three cups of coffee per day were 30 percent less likely to progress. Those who drank three or more cups each day had a 53 percent lower risk.
There was no connection between tea intake and liver disease progression.
In theory, there are several ways coffee could help protect the liver, according to Freedman’s team. One is by altering activity in the blood-sugar-regulating hormone insulin; coffee drinkers in this study tended to have lower blood levels of insulin.
Coffee also contains a number of antioxidant compounds, making it possible that the beverage protects liver tissue from cell-damaging substances in the body called reactive oxygen species.
However, Freedman and his colleagues point out, coffee is composed of more than 1,000 chemical compounds, and more research is needed to understand whether and why coffee might protect the liver.
SOURCE: Hepatology, November 2009.