News Review From Harvard Medical School -- Excess Weight, Drinking Boost Liver Damage
Overweight women who drink too much alcohol greatly increase their risk of liver damage, a new study finds. The study included more than 107,000 women. Researchers divided them into groups based on weight and how much alcohol they drank. Overweight women who drank heavily had three times the risk of chronic liver disease (cirrhosis) and death as light drinkers of normal weight. Heavy drinking was defined as more than 15 units of alcohol per week. One unit is equal to 25 milliliters (ml) of whisky (about 1 ounce) or half of a 175 ml glass of wine. A second study also found a higher risk of liver cancer for people who had fatty liver disease and were overweight, obese or had type 2 diabetes. Both studies were presented at a conference. HealthDay News wrote about them April 27.
By Howard LeWine, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
Fatty liver disease has become extremely common. Some estimates suggest as many as 20% of Americans have too much liver fat.
Not that long ago, fatty liver was linked mainly with overuse of alcohol. Now the main reasons for fatty liver are the epidemics of obesity and type 2 diabetes. Fatty liver affects 70% to 90% of people with those conditions. It's not surprising that, as obesity and diabetes have become more common, so has fatty liver disease.
Fatty liver disease occurs when abnormal amounts of fat make their way into liver cells. Having those fattened cells can lead to inflammation in the liver. The inflammation damages surrounding liver tissue.
If alcohol is the culprit, doctors call it alcoholic hepatitis. If excess alcohol is not involved, it's called nonalcoholic steatohepatitis. "Steato" refers to fat. "Hepatitis" means that the liver is inflamed.
The short name for nonalcoholic steatohepatitis is NASH. About 5% to 10% of people with fatty liver disease go on to develop NASH.
Alcoholic hepatitis can get better if people stop drinking soon enough. NASH is often a relatively stable, low-grade condition. People generally have no symptoms. But the fat build-up from either problem can start a cascade of serious damage to the liver. This can lead to cirrhosis and liver cancer.
These two studies confirm what experts have expected for some time. People who drink too much alcohol and have obesity or type 2 diabetes have a much higher risk of developing liver failure from cirrhosis and liver cancer.
What Changes Can I Make Now?
The best ways to help avoid and treat fatty liver are similar to the recommendations that keep your heart healthy and prevent type 2 diabetes:
- Maintain a healthy weight and lose weight if necessary.
- Stay as physically active as possible all day long. If you have a desk job, consider setting up your work station to stand most of the time.
- Schedule dedicated exercise time of at least 30 minutes per day.
In people who already have nonalcoholic fatty liver, weight loss seems to have a very direct effect. As people lose weight, the fatty liver becomes less fatty. Crash dieting is a bad idea. Rapid weight loss (four pounds a week or more) can wind up damaging the liver.
Ideally, anyone who has fatty liver should avoid alcohol. Based on these studies, having more than one drink per day for women or two per day for men adds to the risk of liver failure and liver cancer. However, it's not as clear whether an occasional drink (no more than one per day, on average) increases the risk.
What Can I Expect Looking to the Future?
Alcohol and liver problems are well known. But liver damage related to excess weight or diabetes has received less attention. The heart has been the greater worry for people with these problems. And a little alcohol is said to be good for the heart.
Perhaps we need to acknowledge that even a little alcohol might not be best for people at risk of fatty liver.