Many of you are concerned about combating high cholesterol, high blood pressure, diabetes and the battle of the bulge. When all of these issues are out of control—and they are for one-third of American adults—you’ve got a major health condition called metabolic syndrome. One of the unseen but ultimately devastating consequences of metabolic syndrome is liver damage. And while people really do need to put in a lot of effort to keep on top of blood sugar control and cardiovascular health, there is one very pleasant and easy thing they can do to help save their livers—drink coffee!
That’s right—coffee can save your liver. Bottom Line previously reported that drinking coffee was shown to help prevent liver cancer, but coffee’s powers are far more broad-reaching. The big news among hepatologists—people who specialize in researching and treating liver disease—is that two to three cups of “Joe” a day can help keep inflammation, liver fibrosis (patchy scarring of liver tissue) and cirrhosis (widespread liver fibrosis) from getting worse whether it is caused by metabolic syndrome or diabetes or high cholesterol alone.
A research team led by Sammy Saab, MD, MPH, of the Pfleger Liver Institute at the University of California in Los Angeles recently reviewed all of the scientific studies on coffee drinking and liver health published between 1986 and 2012. They revealed that nonalcoholic fatty liver disease (a common consequence of metabolic syndrome) as well as several other chronic liver diseases are significantly less likely to develop in people who drink coffee compared with those who do not. Even among extremely obese people who have fatty liver disease, the livers of those who drank coffee were less damaged than the livers of non-coffee drinkers, underscoring coffee’s protective effect. And coffee drinking was even shown to help people infected with the hepatitis C virus respond better to antiviral therapy.
REGULAR OR DECAF?
Researchers speculate that caffeine plays a role in coffee’s ability to protect the liver, but studies have also shown that tea and other caffeinated beverages don’t produce the same effects in terms of liver health. The latest thinking is that a range of other compounds, besides caffeine, might be behind coffee’s magic. Findings from studies looking at the impact of decaffeinated coffee on the liver have varied, but a very recent study that involved 27,793 adults found that decaffeinated coffee had just as good an effect on liver enzymes as regular coffee. (When one or another liver enzyme is out of whack, it signals liver toxicity—a sign for doctors that a problem such as fibrosis, hepatitis or any number of liver diseases might be brewing.)
In this study, researchers recorded information on how much coffee each participant drank in a 24-hour period and analyzed liver enzymes from blood draws. Participants who reported drinking three or more cups of coffee per day had lower, more normal liver-enzyme levels than participants who were not coffee drinkers. Frequent coffee drinkers were 18% to 31% less likely to have an abnormality with one or another liver enzyme compared with non-coffee drinkers. And when the researchers compared people who drank regular coffee with those who drank decaf, no difference was found.
That’s promising news for people who are sensitive to caffeine but want to partake of coffee’s benefits. There is still a slight catch, though. Not just any coffee product or method of preparation will do when it comes to optimizing liver health. According to the scientific literature review, filtered coffee—the kind brewed using a paper filter—is the magic liver tonic, not unfiltered barista-style coffee, coffee made in a French press or espresso. Why filtered coffee has a benefit over nonfiltered isn’t clear. Also, research has not yet addressed whether drinking coffee black or with milk or sugar makes a difference in the results. While more studies are needed for scientists to pinpoint which of the 100-odd compounds within coffee really do the trick and exactly how much coffee is optimal, the bulk of the evidence now supports the idea that drinking two to three cups of coffee per day can be very, very good for your liver.