We can reverse one of the most common and insidious complications of diabetes when we walk just a little more. From 50 to 70 percent of people with type 2 diabetes and 95 percent of those who are obese have fatty liver. But up to 77 percent of people who have fatty liver don't have any symptoms.
A study that the journal Hepatology just published in its July issue put 141 participants through an exercise program for three months. The participants had nonalcoholic fatty liver disease (NAFLD), sometimes called nonalcoholic steatohepatitis (NASH).
If it leads to cirrhosis of the liver, it's fatal, unless you are lucky enough to get a liver transplant. Liver transplants may be available for people under 70 and my wife was only 69 when her doctor told her that she had cirrhosis. But he also told her that her weight makes a successful transplant unlikely, so two years ago she died from this awful complication of diabetes.
Most of us know that cirrhosis of the liver can be a 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.
The researchers encouraged the participants in the new study to walk more, specifically to get 150 minutes per week of moderate-intensity exercise for their health and to target more than 200 minutes per week to lose weight. With an average BMI of 32, the participants in the study were obese and did need to lose weight.
But one-fourth of the participants increased their exercise by only 60 minutes per week. This turned out to be fortuitous.
"Those who increased their physical activity by even a small amount -- 60 to 119 minutes per week -- showed similar reductions in liver enzymes compared to those who increased physical activity by about four hours," the study says. In other words, they found no dose-response effective for an increase in exercise of more than 60 minutes per week.
"I like the fact that 60 minutes a week is enough for NASH," my favorite Certified Diabetes Educator wrote me. "This should help get the depressed or skeptical NASH-afflicted couch potatoes to start moving around! That's just 10 minutes six days a week!"
Our liver is, of course, only one of our organs that those of us who have diabetes need to protect. Getting more than 60 minutes of exercise per week is certainly better for the rest of our body, and we will feel better then too. But when we start to walk just 10 more minutes six days a week we can start to overcome exercise inertia and prevent our fatty liver problems from getting a lot worse.
Update September 16, 2009:
Here's confirmation in another study. When people who have had a sedentary lifestyle and then start routine physical activities are able to reduce their risk of nonalcoholic fatty liver disease, according to a study in a forthcoming issue of Hepatology. For more information, please see "Exercise helps liver directly."