Scientists discover natural hormone that burns fat by boosting metabolism
17 Apr 2026

A team of scientists from the University of Oklahoma has discovered that a naturally occurring hormone, FGF21 (fibroblast growth factor 21), can reverse obesity in mice.

The research, published in the journal Cell Reports, shows that this hormone sends signals to a brain region responsible for controlling metabolism and appetite.

FGF21's role in metabolism and body weight
Drug development

FGF21 has already been identified as a potential target for new therapies, with drugs targeting this pathway currently in clinical trials for MASH (metabolic dysfunction-associated steatohepatitis), a severe form of fatty liver disease.

The lead researcher of the study, Matthew Potthoff, Ph.D., and his team sought to understand how exactly FGF21 produces its effects on metabolism and body weight.

Unexpected brain signaling discovery
Brain signaling

Potthoff revealed that their previous studies had shown FGF21 signals to the brain instead of the liver.

However, they were surprised to find out that it was the hindbrain that received these signals and not the hypothalamus, which is widely known for regulating body weight.

This discovery was unexpected as they initially thought FGF21 would signal to this well-known area of body weight regulation.

FGF21's brain circuit unveiled
Hormonal interaction

FGF21 interacts with two specific parts of the hindbrain, the nucleus of the solitary tract (NTS) and area postrema (AP).

These regions then send signals to another brain structure called the parabrachial nucleus.

This signaling chain is critical for FGF21's ability to affect metabolism and promote weight loss.

Potthoff said, "This brain circuit seems to be mediating the effects of FGF21."

Differences between FGF21 and GLP-1 drugs
Drug comparison

Despite targeting similar brain regions, FGF21 and GLP-1 drugs work differently.

While GLP-1 medications suppress appetite and reduce food intake, FGF21 boosts metabolic activity, helping the body burn more energy and lose weight.

Potthoff hopes that understanding this specific circuit could lead to the development of more targeted therapies with fewer side effects than current FGF21 analogs which can cause gastrointestinal issues or even bone loss in some cases.

Hope for new obesity and MASH treatments
Future prospects

Potthoff and his team are hopeful that their research could pave the way for new treatments for obesity and MASH.

He said, "While this study focused on the mechanism of FGF21 to reduce body weight, additional studies are necessary to examine whether this circuit also mediates the ability of FGF21 and FGF21 analogs to reverse MASH."