According to the American Liver Foundation, approximately 2 to 5 percent of American children over the age of 5 have a liver disorder called nonalcoholic fatty liver disease. These children and teens are overwhelmingly overweight or obese. In nonalcoholic fatty liver disease, fat builds up in the liver over time. This fat irritates and scars the liver tissue leading to cirrhosis, a serious liver disease. The presence of cirrhosis can lead to liver cancer or even liver failure. In the past, cirrhosis was seen primarily in alcoholics and those with hepatitis, but doctors are seeing it more in their obese pediatric patients. A simple blood test can help to diagnose this serious liver disease. If you are concerned about your child's weight and it's impact on his or her health, talk to your primary care provider about the best course of action to take.