exercising

Fatty Liver and Exercise

David Mendosa Health Guide September 21, 2008
  • If you read my articles about diabetes here regularly, you might have noticed that I rarely cover four topics in the news:

    1. Knowing the causes of diabetes. This doesn't help us control it.

    2. Learning how to avoid diabetes. This comes too late for most of us.

    3. Reading about great new drugs or treatments in the test tube or even up to phase 2 trials. They might help in a decade or so  -- but not now.

    4. Worrying about the possible complications of our diabetes. This would just add more negativity to our lives.

    Of the 313 articles that I have written here about diabetes in the past three years, I did write 19 of them about complications. But each of them emphasized how to prevent or control one of these complications. That's how I stay positive about the elephant in the room.


    Today I am writing for the second time about one of these complications, fatty liver, and how to prevent it. I know how serious that liver disease can be. My wife, Catherine, who had type 2 diabetes, died one and one-half years ago of liver failure.

    About 20 percent of the general U.S. population has nonalcoholic fatty liver disease. From 50 to 70 percent of people with type 2 diabetes have fatty liver. The difference in those proportions is enough to convince me that having a fatty liver is a complication of diabetes.

    A couple of years ago my doctor thought that I might have fatty liver after I got some routine blood tests. Then, ultrasound confirmed it (since then, I have reversed this condition). That's the way we usually learn that we have this complication.

    Initially, we may not have any symptoms either from diabetes or fatty liver. That's why both conditions are so insidious. No big deal, we may think.

    But uncontrolled, fatty liver can lead to nonalcoholic steatohepatitis (NASH), which doctors sometimes call nonalcoholic fatty liver disease (NAFLD). That in turn can lead to cirrhosis of the liver.

    Unless you can get a liver transplant, cirrhosis is fatal. Liver transplants may be available for people under 70 and my wife was only 69 when she died. But her doctor told her that her weight make a successful transplant unlikely, so she died.

    Cirrhosis a well-known consequence of alcoholism. But more people die of nonalcoholic liver disease than from drinking too much. I know that my wife didn't drink any alcohol.

    Yet it turns out that fatty liver is among the complications of diabetes that submit to many different treatments. In my first article about fatty liver here almost two years ago I reviewed several of them.

    Now, it appears that a little exercise can reverse the levels of fat in our liver by up to 40 percent. A moderate amount of exercise is all that it takes, according to a study by physical fitness experts at the Johns Hopkins University School of Medicine.

    On Friday the researchers presented their findings at the annual meeting of the American Association of Cardiovascular and Pulmonary Rehabilitation. A Johns Hopkins spokesperson sent me the abstract of the study, "Exercise Training Reduces Hepatic Fat in Type 2 Diabetes: A Randomized, Controlled Trial" in Microsoft Word format. Since I couldn't find it online anyplace else, I posted it on my site.


  • The researchers divided 77 men and women with diabetes into two groups and measured the liver fat of 44 of the participants.


    Why only 44 of the 77 participants? I called Dr. Stewart at the annual meeting to find out.

    "When we started the study, we didn't plan to study hepatic fat," he replied. "But after we started, some of my colleagues persuaded me to include it."

    Dr. Stewart says the team's study is the first to specifically demonstrate the beneficial role that exercise plays in controlling hepatic fat levels in people with diabetes.

    The researchers put half of the study participants through a moderate program of sustained aerobic exercise consisting of three weekly 45-minute sessions. The participants could bicycle, run on a treadmill, or take brisk walks. In addition, they lifted stacked weights for about 20 minutes, also three times a week -- and not at a heavy-duty pace. They asked the other half of the participants to avoid any formal aerobic fitness or gym classes.

    Special magnetic resonance imaging scans showed much lower levels of liver fat in the active group, which remained the same in the non-exercising group. The exercising group had 5.6 percent liver fat after six months. The non-exercising group had 8.5 percent.

    Until Dr. Stewart and his team does more studies, we can't tell how significant this is. He says his team's next steps will be to analyze the long-term effect of moderate exercise on diabetes.

    We already knew that exercise makes you feel and look better. It takes glucose out of your blood to use for energy. It helps prevent heart disease, depression, and even some forms of cancer. If you do enough, it will help you to lose weight.

    But sadly, the link between exercise and fatty liver came too late for Catherine. It is timely for everyone else who has type 2 diabetes.