Fatty Liver Disease
Fatty liver, or steatosis, is a term that describes the buildup of fat in the liver. While it’s normal to have some fat in your liver, more than 5 to 10 percent of your liver weight is fat in the case of fatty liver.
Fatty liver is a reversible condition that can be resolved with changed behaviors. It often has no symptoms and typically does not cause permanent damage.
The liver is the second largest organ in the body. The liver’s function is to process everything we eat or drink and filter any harmful substances from the blood. This process is interrupted if too much fat is in the liver. The liver commonly repairs itself by rebuilding new liver cells when the old ones are damaged. When there’s repeated damage to the liver, permanent scarring takes place. This is called cirrhosis.
Fatty liver is common. Around 10 to 20 percent of Americans have too much fat in their liver, but no inflammation or damage is present. Most cases of fatty liver are detected in people between ages 40 and 60. When fatty liver is caused by an underlying condition, it can become harmful to the liver if the cause is not recognized and treated.
What Are the Symptoms of Fatty Liver?
Fatty liver typically has no associated symptoms. You may experience fatigue or vague abdominal discomfort. Your liver may become slightly enlarged, and your doctor can detect this during a physical exam.
Excess fat can cause liver inflammation. If your liver becomes inflamed, you may have a poor appetite, weight loss, abdominal pain, weakness, and confusion.
What Are the Causes of Fatty Liver?
The most common cause of fatty liver is alcoholism and heavy drinking. In many cases, doctors don’t know what causes fatty liver in people who are not alcoholics.
Fatty liver develops when the body creates too much fat or cannot metabolize fat fast enough. The excess fat is stored in liver cells where it accumulates to form fatty liver disease. Eating a high-fat diet may not directly result in fatty liver.
Besides alcoholism, other common causes of fatty liver include:
- hyperlipidemia, or high levels of fats in the blood
- genetic inheritance
- rapid weight loss
- side effect of certain medications, including aspirin, steroids, tamoxifen, and tetracycline
What Are the Types of Fatty Liver?
There are four types of fatty liver.
Nonalcoholic Fatty Liver
Nonalcoholic fatty liver (NAFL) develops when the liver has difficulty breaking down fats, which causes a buildup in the liver tissue. The cause is not related to alcohol. NAFL is diagnosed when more than 10 percent of the liver is fat.
Alcoholic Fatty Liver
Alcoholic fatty liver is the earliest stage of alcohol-related liver disease. Heavy drinking damages the liver, and the liver cannot break down fats as a result. Abstaining from alcohol will likely cause the fatty liver to subside. Within six weeks of not drinking alcohol, the fat will disappear. However, if excessive alcohol use continues, cirrhosis may develop.
Nonalcoholic Steatohepatitis (NASH)
When the fat builds up enough, it will cause the liver to swell. If the original cause is not from alcohol, it’s called nonalcoholic steatohepatitis (NASH). This disease can impair liver function.
Symptoms can be seen with this disease. These include:
- appetite loss
- abdominal pain
- yellowing of the skin (jaundice)
If left untreated, NASH can progress to permanent scarring of the liver and eventual liver failure.
Acute Fatty Liver of Pregnancy
Acute fatty liver is a rare complication of pregnancy that can be life-threatening.
Symptoms begin in the third trimester. These include:
- persistent nausea and vomiting
- pain in the upper-right abdomen
- general malaise
Women who are pregnant will be screened for this condition. Most women improve after delivery and have no lasting effects.
Who’s at Risk for Fatty Liver?
Fatty liver is the buildup of extra fats in the liver, it’s more likely to develop if you’re overweight or obese. Having type 2 diabetes also may increase your risk for fatty liver. Fat accumulation in the liver has been linked to insulin resistance, which is the most common cause of type 2 diabetes.
Other factors that may increase your risk for fatty liver are:
- excessive alcohol use
- taking more than the recommended doses of certain over-the-counter medications, such as acetaminophen
- high cholesterol
- high triglyceride levels
- metabolic syndrome