Coffee Consumption May Protect Heavy Drinkers from Liver Disease, Study
The next time you have a drink, consider replacing your usual with an Irish coffee. Finnish researchers found that heavy coffee consumption may protect men who drink alcohol against liver damage.
The latest study published in the journal Alcohol and Alcoholism included 18,899 Finnish men and women aged 25 to 74. Researchers asked participants about their coffee and alcohol consumption and measured participants' blood levels of the liver enzyme gamma-glutamyl transferase (GGT).
Researchers explain that alcohol consumption raises levels of GGT in the blood, and over time drinking can also lead to alcoholic liver diseases. Previous studies show that people with liver disease often have higher levels of GGT in their blood.
The study found that male participants who consumed more than 24 alcoholic drinks per week, or about 3.5 drinks daily, had the highest levels of GGT, which were about three times higher than men who did not consume alcohol.
However, researchers found that male heavy drinkers who also consumed five or more cups of coffee a day showed an overwhelming 50 percent decrease in their GGT compared with male heavy drinkers who drank no coffee.
However, coffee consumption doesn't seem to benefit female drinkers. Researchers noted that while a similar trend was also observed among women, the association was not significant.
"Our findings suggest a possible protective effect for coffee intake in alcohol consumers," said researcher Dr. Onni Niemelä, of Seinäjoki Central Hospital and the University of Tampere in Finland, according to MyHealthNewsDaily.com.
Other factors that can raise GGT levels include smoking, older age and being overweight. Researchers note that while there were no differences in these variable among heavy drinkers, moderate drinkers, former drinkers and nondrinkers in the study, they say they cannot know for certain that the interaction between alcohol and one of these factors affected the study results.
Researchers also noted that participants might not have accurately recalled the amount of coffee and alcohol they consumed.
Past research has also suggested that coffee consumption may decrease GGT levels, and that caffeine may be partly responsible for the decrease.
However, other experts warn that while the study id though provoking, it is "impossible to derive meaning from them," Dr. David Bernstein, chief of the division of hepatology at North Shore University Hospital in Manhasset, New York, who was not involved in the new study, told MyHealthNewsDaily.
He says the studies have still not established a definitive link between elevated levels of GGT and symptoms of liver disease.
"If I go out and have a six-pack tonight, my levels will be up, but it doesn't mean I have liver disease," Bernstein explained.
He warns that drinkers should not think drinking more coffee will erase the harmful effects of heavy drinking.
"We know nothing about whether decreasing levels of the liver enzyme leads to improvements in overall health, or a decreased risk of liver disease," Bernstein said.
Nonetheless, researchers from the current study call for further investigation into the "possible hepatoprotective effects of coffee in alcohol consumers," according to the study.