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.
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.
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:
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.
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
If your liver is inflamed, your doctor can detect it by examining your abdomen. Let your doctor know if you have been experiencing fatigue or loss of appetite. Also, tell your doctor about any history of alcohol, medication, and supplement use.
Your doctor may find that liver enzymes are higher than normal on a routine blood test. This doesn’t confirm a diagnosis of fatty liver. Further analysis is necessary to find the cause of the inflammation.
The fat on your liver will show up as a white area on the ultrasound image. Other imaging studies may also be done, such as CT or MRI scans. Imaging studies can detect fat in the liver, but they cannot help your doctor confirm any further damage.
In a liver biopsy, your doctor will insert a needle into the liver to remove a piece of tissue for examination. Your doctor will give you a local anesthetic to lessen the pain. This is the only way to know for certain if you have fatty liver. The biopsy will also help your doctor determine the exact cause.
There isn’t a medication or surgery to treat fatty liver. Instead, your doctor will offer recommendations to reduce your risk factors. These recommendations include:
- limiting or avoiding alcoholic beverages
- managing your cholesterol
- losing weight
- controlling your blood sugar
If you have fatty liver because of obesity or unhealthy eating habits, your doctor may also suggest that you increase physical activity and eliminate certain types of food from your diet. Reducing the number of calories you eat each day can help you lose weight and heal your liver.
You can also reverse fatty liver disease by reducing or eliminating fatty foods and foods high in sugar from your diet. Choose healthier foods like fresh fruits, vegetables, and whole grains. Replace red meats with lean animal proteins like chicken and fish.
Protecting your liver is one of the best ways to prevent fatty liver. If you choose to drink alcoholic beverages, do so in moderation. According to the Centers for Disease Control and Prevention (CDC), “moderate alcohol consumption is defined as having up to one drink per day for women and up to two drinks per day for men.”
Follow your doctor’s instructions, and take medications for diabetes or high cholesterol as directed. Additionally, aim for at least 30 minutes of exercise most days of the week to maintain a healthy weight.
Fortunately, many cases of fatty liver don’t develop into liver disease. The liver can repair itself, so if you take the necessary steps to treat high cholesterol, diabetes, or obesity, you can reverse your fatty liver. If you’re a heavy drinker, stopping drinking may heal your liver completely. A liver biopsy can help your doctor identify permanent liver damage, as well as determine the severity of damage and the best way to treat it.