How dangerous is a fatty liver (hepatic steatosis)?

A fatty liver, also known as MASLD or NAFLD, is one of the most common chronic liver conditions: more than a quarter of all adults are affected. Most people do not know this, because symptoms are barely noticeable. Sometimes a little fatigue or a bloated feeling in the abdomen, but most of the time it is only discovered by chance, through a blood test or an ultrasound.

The greatest threat does not come from the liver itself, but from the heart. Several large studies show that cardiovascular disease is the leading cause of death in people with a fatty liver. That risk is elevated, even independent of classic risk factors such as high blood pressure or high cholesterol. Heart rhythm disorders and a weakened heart muscle also occur more frequently. Your heart therefore deserves at least as much attention as your liver.

Serious liver complications are less often the problem. Only 3 to 5 percent ultimately develop cirrhosis, scar tissue in the liver, and that typically takes more than twenty years. In rare cases, cirrhosis can progress to liver cancer. Most people with a fatty liver never reach that stage.

Whether you belong to that small group who do develop problems depends on several factors: insulin resistance, an unhealthy diet, a disrupted gut microbiome, and genetic predisposition. Abdominal fat plays a major role. Up to eighty percent of people with fatty liver are overweight. Fat around the organs releases harmful fatty acids and inflammatory substances directly into the liver.

There are no approved medications for a fatty liver; drugs in development have had only a modest effect. Treatment revolves entirely around lifestyle: eating more healthily, losing weight, and exercising more. Good news: people who lose weight and reduce abdominal fat tackle both the liver and the heart risk at the same time^{1,2,3,4,5,6,7}.