Liver Health UK Team
The Complete Guide to Understanding Fatty Liver and NASH
Updated: Oct 17, 2022
Introduction: What is Liver Disease?
Liver disease is a general term that refers to any disorder that causes liver damage. The liver is responsible for filtering out toxins and waste material from the blood, so when it is damaged, its ability to do this job can be impaired.
The liver is also responsible for making bile, which helps break down fats and absorb vitamins. When the liver isn't healthy, it can't make enough bile or filter out harmful substances in the bloodstream. This can lead to a buildup of fat in the body and vitamin deficiencies.
The most common liver disease in Western countries is NAFLD which affects between 17% and 46% of adults. The term “NAFLD” stands for Non-alcoholic fatty liver disease. It is characterized by the accumulation of fat inside the liver cells, which causes inflammation and scarring of the organ. While the fat buildup in the liver is often the result of alcohol abuse, NAFLD is not the result of alcoholism.
Types of NAFLD
NAFLD is a term for a spectrum of conditions which ranges from simple fatty liver to Nonalcoholic steatohepatitis (NASH). The latter is a progressive disease that can lead to serious complications in the future, like cirrhosis. Fatty liver, on the other hand, is a reversible condition, but it can also progress to NASH if left untreated.
Simple fatty liver is a form of NAFLD. People suffering from fatty liver have excess fat built up in their liver but very little or no inflammation or cell damage. Simple fatty liver normally does not cause liver damage or complications.
NASH is a form of NAFLD that not only causes the accumulation of fat in the liver but also causes hepatitis—inflammation of the liver—and the damage to the liver cells. Inflammation and liver cell damage often cause scarring of the liver or fibrosis. NASH also may cause cirrhosis of the liver or liver cancer.
Symptoms and Diagnosis
The symptoms of liver disease are often vague and nonspecific. People with fatty liver disease often don't feel any symptoms before the disease progresses to cirrhosis. Similarly, in the early stages of NASH the symptoms are often silent, making it difficult to diagnose.
Generally symptoms of liver disease may include:
Loss of appetite
Nausea or vomiting
A diagnosis for fatty liver and NASH is not made by a single test. It is based on a combination of factors such as the patient’s symptoms, the results of blood tests, and the results of imaging tests. The most common imaging test for fatty liver is an MRI. An MRI will show if there are any signs of inflammation in the liver and if there are any deposits of fat in the liver.
How are They Treated?
Weight loss is the most common treatment for all forms of nonalcoholic fatty liver disease (NAFLD) – simple fatty liver and NASH. Weight loss can reduce fat in the liver, reduce inflammation and fibrosis, even scarring. Losing at least 3% of body weight can reduce fat in the liver, but to reduce liver inflammation patients need to lose up to 10% of body weight.
No medication is recommended for the treatment of fatty liver or NASH. The meds are recommended only to treat underlying conditions such as diabetes or heart disease.