For years, fatty liver disease was viewed mainly as a liver problem. Doctors focused on the damage it could cause inside the liver and the risk of long-term complications. Now, a growing body of research is changing that picture in a major way.

Recent studies suggest that fatty liver disease may also be a powerful warning sign for heart trouble. Researchers are finding that people with excess fat in the liver face a much higher risk of heart attacks, serious chest pain, and other cardiovascular events. Some experts now believe fatty liver disease should be considered a key marker of heart disease risk, not just a liver condition.

A major study led by Harvard Medical School has added fresh evidence to this connection. The findings are pushing doctors to rethink how they screen, monitor, and treat patients with fatty liver disease.

The Strong Connection Between Fatty Liver & Heart Attacks

Olly / Pexels / The Harvard-led research examined 3,637 adults who were being evaluated for chest pain. More than one in four participants had fatty liver disease, AKA hepatic steatosis.

Researchers followed these individuals for two years to track their health outcomes.

The results were striking. About 4.1% of people with fatty liver disease experienced a major cardiovascular event, including a heart attack, hospitalization for severe chest pain, or death. Among people without fatty liver disease, that number was only 2.5%. Even after accounting for common heart risk factors such as obesity, high blood pressure, and high cholesterol, fatty liver disease remained linked to a significantly higher risk.

Researchers calculated that people with fatty liver disease had a 69% greater chance of experiencing a serious heart-related event. That increased risk persisted even when doctors adjusted for blocked heart arteries. This suggests that fatty liver disease contributes to heart problems through several biological pathways, not just through traditional cardiovascular risk factors.

These findings support a growing view among specialists. Fatty liver disease is not an isolated condition. It affects multiple systems throughout the body and can influence heart health in ways that were not fully understood a decade ago.

What Happens Inside the Arteries?

One of the most important discoveries involves the type of plaque found in the heart's arteries. The Harvard study found that people with fatty liver disease carried roughly 15% more total plaque inside their coronary arteries.

More concerning was the amount of noncalcified plaque. Researchers found approximately 24% more of this dangerous plaque type in people with fatty liver disease. Unlike hardened plaque, noncalcified plaque is softer and packed with fat. That makes it more unstable and more likely to rupture.

When a plaque ruptures, the body quickly forms a blood clot. If that clot blocks blood flow to the heart, a heart attack can occur. Researchers believe this unstable plaque helps explain why fatty liver disease increases cardiovascular risk.

The plaque burden did not explain the entire connection. Scientists estimate it accounted for only a portion of the increased risk. That finding points to additional biological factors linking the liver and the heart.

Why Doctors Now Call It MASLD?

Kindel / Pexels / Medical experts have recently adopted a new name for fatty liver disease. The condition is now often called Metabolically Dysregulated Associated Steatotic Liver Disease, or MASLD.

The updated term reflects a better understanding of the disease. MASLD is closely tied to insulin resistance, obesity, abnormal cholesterol levels, and other metabolic problems. These same issues also increase the risk of cardiovascular disease.

Researchers now describe the relationship between the liver and the heart as a two-way communication network. The fatty liver releases inflammatory proteins, hormones, and signaling molecules into the bloodstream. These substances can affect blood vessels and the heart's function.

Chronic inflammation appears to be one of the biggest drivers. Persistent low-grade inflammation can damage arterial walls, promote plaque formation, and increase the risk of cardiovascular disease. At the same time, oxidative stress and blood vessel dysfunction add to the problem.