What is Non-Alcoholic Liver Disease?
Non Alcoholic Fatty Liver Disease (or NAFLD) is an extremely common cause of liver test abnormalities in America. NAFLD is a state I which excess fat fills liver cells. This can involve any where from 5% to 90% of the liver. 30 million Americans may be affected.
What is the Cause of NAFLD?
This abnormal storage of fat in the liver is generally associated with being overweight, diabetes, high cholesterol, and high blood pressure. Heavy use of alcohol can also cause excess fat in the liver. Generally 20-30 grams/daily of alcohol can be consumed by men and 10-15 grams per day by women without significant injury to the liver. Heavier alcohol use as well as other types of liver disease must be ruled out by a physician before NAFLD can be diagnosed
How is NAFLD diagnosed?
Most often NAFLD is found by accident when a patient receives and abdominal scan to work up a complaint and the scan incidentally indicates fat in the liver. Alternatively, a patient my have basic lab work performed and find that their "liver function tests" (AST, ALT, or Bilirubin) are abnormal. This often leads to an evaluation and the discovery of excess fat in the liver. A definitive diagnosis of fatty liver can be made with liver biopsy; however, liver biopsy can often be avoided.
Is NAFLD harmful?
NAFLD can be harmful to some patients. About 1 out of 10 patients with fat in their liver will also develop inflammation and scarring of their liver. Unfortunately, it is difficult to predict who will or wont develop permanent damage to their liver and who will simply have fat but no lasting issues. A doctor can you gauge your risk and follow you over time for improvement or worsening. Only a small percentage of Americans with fatty liver will one day need liver transplant; but because so many Americans have fatty liver NAFLD will one day be the number one cause for liver transplants in the US. What forgotten message about NAFLD is that patient's with NAFLD are at higher risk for heart attack and stroke due to the increased weight, diabetes, or high blood pressure they might also have. A diagnosis of fatty liver is often a sign that an overall improvement in health and fitness is needed.
How is NAFLD treated?
The best studied and surest way to reverse fatty liver is to lose weight. Generally a loss of 5% to 10% of body weight will remove significant fat and inflammation from the liver. Low calorie and low carbohydrate diets have both been shown to be effective in removing fat from the liver. Cardiovascular exercise and intense resistance traning 4 x a week can also improve NAFLD.
There are currently no FDA approved medications for fatty liver disease. However, A well done government funded study seems to suggest Vitamin E supplements at 800 IU a day or the diabetes medication pioglitazone can help reverse fat and inflammation of the liver. Many new medications are being tested for fatty liver. Hopefully some of the new medications will be safe and effective.
Weight loss surgery is sometimes considered for heavy patients with diabetes and high blood pressure. There is reasonable evidence that weight loss surgery improves liver fat as well in most patients. Long term effects of modern weight loss surgery techniques on the liver are still not known.
Non Alcoholic Fatty Liver Disease