Fatty Liver (medical term: hepatic steatosis) describes the abnormal buildup of fat inside liver cells. A healthy liver normally contains less than 5% fat. When the fat content rises significantly above this level, the liver is considered fatty.
Causes #
There are two main types:
- Non-alcoholic fatty liver disease (NAFLD)
This form develops independently of alcohol consumption. Common causes include overweight/obesity, lack of physical activity, a high-calorie diet (especially rich in sugar and saturated fats), insulin resistance, or type 2 diabetes. Certain medications and metabolic disorders can also play a role. - Alcoholic fatty liver disease (AFLD)
Regular, excessive alcohol intake causes increased fat storage in liver cells within a relatively short time. The breakdown of alcohol puts major strain on metabolism—especially fat metabolism—so fats are no longer burned but instead accumulate in the liver.
Stages #
Fatty liver is not a static condition; it can worsen or improve. The main stages are:
- Simple fatty liver (hepatic steatosis)
Fat accumulates in liver cells without significant inflammation. This early stage is frequently symptom-free and reversible if the triggering factors are eliminated. - Steatohepatitis
Inflammation develops in addition to fat buildup. The non-alcoholic form is called NASH (non-alcoholic steatohepatitis), the alcohol-related form ASH (alcoholic steatohepatitis). At this point, actual damage to liver cells occurs. - Fibrosis and cirrhosis
Repeated inflammation leads to scar tissue formation (fibrosis). If the process continues, liver cirrhosis develops—a serious, usually irreversible remodeling of the entire liver tissue.
Consequences for Metabolism #
Fatty liver is far more than a local liver issue; it affects the entire body:
- Insulin resistance: Fatty liver cells respond poorly to insulin, promoting the development of type 2 diabetes.
- Disturbances in lipid metabolism: Elevated blood lipids (triglycerides, LDL cholesterol) increase cardiovascular risk.
- Inflammatory processes: The fatty liver releases signaling molecules that raise the risk of cardiometabolic diseases.
- Alcohol burden: Continued drinking dramatically increases the chance that fatty liver will progress to the next, more dangerous stage—even small amounts can accelerate damage.
Alcohol and Fatty Liver #
Alcohol burdens the liver in two major ways:
- Its breakdown alters the NADH/NAD⁺ ratio in the liver, blocking normal fat burning. NADH/NAD⁺ is a key molecule in energy metabolism: NAD⁺ accepts electrons and becomes NADH, which then passes energy along in the form of electrons.
- Even modest amounts of alcohol in someone who already has non-alcoholic fatty liver significantly raise the risk of developing steatohepatitis.
- Regular drinking greatly accelerates progression toward cirrhosis.
Prognosis #
In its early stages, fatty liver is usually fully reversible through lifestyle changes: complete alcohol abstinence, weight loss, balanced nutrition, and regular physical activity. Once significant fibrosis or cirrhosis has developed, complete healing is rarely possible. That makes early detection and decisive action extremely important.
If fatty liver is already present, staying completely alcohol-free is by far the safest choice. Even small amounts of alcohol can promote inflammation and speed up scarring.
Fatty Liver – Frequently Asked Questions (FAQ) #
What is fatty liver?
Fatty liver means too much fat has accumulated inside liver cells. When the fat percentage clearly exceeds the normal range, the condition is called steatosis. The early stage is often low in symptoms and can reverse itself.
The non-alcoholic form is mainly caused by overweight, excessive calories, insulin resistance, and lack of exercise. The alcoholic form is triggered by regular alcohol consumption. Both eventually lead to fat storage in the liver.What is the difference between non-alcoholic and alcoholic fatty liver?
The first stage is simple steatosis. This is followed by steatohepatitis—non-alcoholic as NASH and alcoholic as ASH. Repeated inflammation leads to fibrosis and, in the final stage, to cirrhosis.What stages does fatty liver have?
Many people feel nothing at all. Possible signs include fatigue, pressure in the right upper abdomen, and reduced physical capacity. A doctor diagnoses it using blood tests, ultrasound, and—if necessary—elastography or liver biopsy.How do I know if I have fatty liver?
It promotes insulin resistance and raises blood lipids. This increases the risk of type 2 diabetes and cardiovascular diseases. Inflammatory signaling molecules from the liver drive the process forward.What effects does fatty liver have on metabolism?
Alcohol shifts the NADH/NAD⁺ ratio in the liver and blocks fat burning. Even small amounts raise the risk of steatohepatitis and accelerate the progression to fibrosis and cirrhosis.What role does alcohol play in existing fatty liver?
Yes. Weight loss, more exercise, less sugar, and strict alcohol abstinence are the most important factors. In early stages, the liver often normalizes within months.Can fatty liver reverse itself?
Lifestyle changes are the decisive factor. Effective medications exist for accompanying conditions like diabetes. Supplements can provide support but cannot replace weight loss, dietary correction, and alcohol abstinence.Are there medications or supplements for fatty liver?
Bernd Guzek, MD, PhD #
Physician, author & co-founder of Bye-Bye-Booze
Specialized in biochemical mechanisms of addiction and brain metabolism.
