Metabolic dysfunction-associated steatotic liver disease (MASLD) affects nearly one in three people worldwide, yet until now, doctors have had few targeted treatments to offer. A recent discovery suggests that something as familiar as vitamin B3 could hold the key to slowing—or even reversing—the disease.
Researchers from South Korea have pinpointed a genetic trigger that fuels fatty liver disease and found that niacin, a form of vitamin B3, can counteract its effects. The findings, published in Metabolism, open the door to repurposing a safe, widely available compound for a condition that has reached epidemic levels. Here’s what the study uncovered and why experts are hopeful.
A closer look at the MASLD study
The research team, led by Professor Jang Hyun Choi of the Ulsan National Institute of Science and Technology, focused on a small molecule called microRNA-93 (miR-93). This molecule, present in liver cells, acts like a switch that controls how certain genes function. In both human patients with MASLD and in experimental animal models, miR-93 was found at unusually high levels.
When miR-93 is overactive, it blocks the activity of SIRT1, a gene crucial for regulating fat metabolism in the liver. This disruption drives the buildup of fat, inflammation, and eventually scarring of liver tissue. In laboratory experiments, mice engineered to overproduce miR-93 developed severe fatty liver disease, while blocking miR-93 dramatically improved their liver health.
These results highlight miR-93 as a key culprit in how MASLD develops and progresses. More importantly, they point to a new way of treating the disease by targeting its genetic roots.
How vitamin B3 fits in
After screening 150 FDA-approved drugs, the researchers found that niacin (vitamin B3) was the most effective at suppressing miR-93 activity. In mice, niacin treatment lowered miR-93 levels, boosted SIRT1 function, and restored balance to fat metabolism in the liver. This not only reduced fat accumulation but also improved insulin sensitivity and other metabolic markers.
What makes this discovery particularly promising is that niacin is already a well-established medication used for conditions like high cholesterol. Its safety profile is well understood, making it a strong candidate for repurposing in liver disease.
As the researchers explained, “This study precisely elucidates the molecular origin of MASLD and demonstrates the potential for repurposing an already approved vitamin compound to modulate this pathway, which has high translational clinical relevance”.
The idea of using niacin for fatty liver disease could also open doors for combination therapies. Pairing vitamin B3 with other treatments targeting metabolic dysfunction might help slow or reverse the disease in people at high risk. Still, human clinical trials will be needed before doctors can recommend niacin as a frontline therapy.
MASLD has quietly become the most common liver disorder in the world, often linked to obesity, type 2 diabetes, and metabolic syndrome. The discovery that a simple vitamin may help combat the condition is an encouraging step, especially given the lack of targeted drugs available. While more research is needed, this study suggests that vitamin B3 might become a powerful tool in the fight against fatty liver disease.