The obesity epidemic has led to an increase in the number of people who have a form of liver disease known as nonalcoholic fatty liver disease, or NAFLD. The disease can cause dangerous levels of fat to build up in the liver and is a serious health risk. Of even greater concern, NAFLD is a progressive disease that leads to liver scarring (cirrhosis) and liver cancer. There are no treatments for advanced forms of the disease. Slowing down or reversing NAFLD can save lives. This new research suggests that exercise could help people at high risk for the more severe forms of NAFLD. The results support the idea of using exercise to treat patients with long-term diseases like NAFLD.