What metabolic fatty liver disease is
Metabolic fatty liver disease is a buildup of fat inside liver cells driven by excess weight and metabolic problems rather than heavy drinking. Its name has changed: the condition long called NAFLD is now usually called metabolic dysfunction-associated steatotic liver disease, or MASLD, and its inflamed form, once NASH, is now MASH. The NIDDK uses both sets of names.
It is common. The NIDDK notes that it is one of the most common causes of liver disease in the United States, and research suggests it is present in up to 75 percent of people with overweight and more than 90 percent of people with severe obesity. The simple fatty form can stay stable for years; the inflamed form can progress to scarring (fibrosis), cirrhosis and liver cancer.
Signs and symptoms
Most men with fatty liver feel nothing, which is why it is usually found by accident. When symptoms do appear, they tend to be vague:
- Tiredness that does not match your schedule.
- A dull ache or fullness under the right ribs.
- An enlarged liver noticed on an exam or scan done for something else.
Signs of advanced disease, such as yellowing skin or eyes, a swollen belly, easy bruising or confusion, appear late and need urgent attention.
How it is usually flagged: ALT and AST
The most common first clue is a routine blood test with raised liver enzymes. MedlinePlus explains that ALT and AST are enzymes made mainly in the liver, and that abnormal results do not always mean liver disease, so providers interpret them alongside symptoms, history and medicines.
In fatty liver, ALT is often higher than AST, and both may be only mildly raised. Reference ranges vary from lab to lab. Other causes of raised enzymes need to be considered too: alcohol, viral hepatitis, iron overload, some medicines and supplements, and even a hard workout before the draw. Our pages on ALT and AST liver enzymes and high liver enzymes after lifting explain how those numbers are read.
Why visceral fat and low testosterone travel with it
Fatty liver rarely shows up alone. It sits in a cluster with visceral fat, insulin resistance, high triglycerides and low HDL, the same cluster that defines metabolic syndrome. Fat packed around the organs releases fatty acids straight to the liver, which is one reason waist size predicts liver fat better than weight alone. Our page on visceral fat in men explains how that fat is measured.
Testosterone is part of the picture in men. A 2017 meta-analysis of observational studies covering more than 13,000 men found that men with fatty liver had lower total testosterone, by about 2.8 nmol/L (roughly 80 ng/dL), and that higher testosterone was tied to lower odds of the condition. These studies show an association, not proof that low testosterone causes fatty liver; excess weight and insulin resistance lower both.
How it is evaluated
A useful workup answers two questions: is there fat in the liver, and is there scarring?
- Blood tests: ALT, AST, GGT, bilirubin and albumin; a platelet count; HbA1c and fasting glucose; a lipid panel; and, when relevant, hepatitis and iron studies. The clinic’s liver and kidney function panel covers the core markers.
- Scarring risk: simple scores built from age, AST, ALT and platelets help decide who needs further testing.
- Imaging: ultrasound or elastography, which measures liver stiffness, is arranged through your primary care doctor or a specialist when scores or enzymes suggest it.
- Body composition and waist size, which track visceral fat over time.
- Testosterone, when symptoms or metabolic risk suggest it.
Weight loss is the main lever
Weight loss is the core treatment for metabolic fatty liver, and the amount matters. The NIDDK states that losing at least 3 to 5 percent of body weight can reduce liver fat, and losing up to 7 to 10 percent may be needed to reduce inflammation and fibrosis. It also advises losing weight gradually, since rapid loss and malnutrition can make liver disease worse, and notes that physical activity helps even without weight loss.
Medication now has a defined role. In August 2025 the FDA approved Wegovy (semaglutide) under accelerated approval to treat MASH in adults with moderate-to-advanced fibrosis, alongside diet and exercise. Whether a man qualifies for that indication is a specialist question that depends on staging.
For men whose fatty liver sits alongside excess weight, Ultimate Male’s medical weight loss program uses semaglutide or tirzepatide when criteria are met, with body composition tracking and paced, supervised loss. Liver enzymes are rechecked as weight comes down, which turns an abstract goal into a number you can watch. Our page on semaglutide for fatty liver covers the evidence in more depth.
What helps besides the scale
A few other changes support the liver while weight comes down. Cutting sugary drinks and large amounts of refined carbohydrate lowers the fat the liver is asked to make. Regular exercise, both aerobic and resistance, reduces liver fat in its own right. Bringing blood sugar, triglycerides and blood pressure into range treats the same metabolic engine that drives the condition. Alcohol is worth cutting back hard, and stopping is often advised once scarring is suspected. Supplements marketed as liver cleanses are worth skipping, because some herbal and bodybuilding products can injure the liver themselves, as our page on whether supplements can damage your liver explains.
When liver symptoms are urgent
Go to the emergency room or call 911 for yellowing of the skin or eyes with confusion or drowsiness, vomiting blood, black or tarry stools, or a rapidly swelling belly. These are signs of advanced liver disease or bleeding and should not wait for a clinic visit.
Your next step
If a routine test showed raised ALT or AST, or you carry weight around your middle, a focused visit can sort out what the numbers mean. Ultimate Male offers a free 10-minute phone call at 626-319-5261, same-day blood draws at San Gabriel and Downey, and a one-on-one review with a PA-C or MD. When imaging or a liver specialist is needed, the clinic coordinates with your primary care doctor. Book a visit online when you are ready.
