A new study indicates that leptin, or the “fat hormone,” are likely involved in hearing and vision loss, on top of weight gain.

Researchers wrote within the journal General and Comparative Endocrinology that leptin could ultimately help doctors better understand sensory loss in humans.

During the study, the scientists could develop zebrafish that were able to produce low leptin.

While staring at the zebrafish, scientists assumed the leptin-deficient fish would be unable to metabolize fat. However, they did not expect to find it affects the development of sensory systems.

“We learned that leptin influences the development of eyes and ears in fish,” Richard Londraville, University of Akron professor of biology, said inside a pr release.

Previous studies in mice discovered that leptin controls body temperature, immune functions and bone strength and density. These studies also says leptin loss may also affect eye and ear rise in mice.

Now, the team has determined a drop in leptin dramatically alters zebrafish development, that could have similar effects on humans.

“There is some evidence that leptin deficiencies in fish have in all probability the same impact on humans, so this may be pointing toward some thing widespread than we thought,” Londraville said within the release. “Perhaps more research ought to be allocated to the sensory effects of leptin, which hasn’t received much attention.”

The team received an additional $435,000 grant in the National Institutes of Health to further their research. The scientists will be while using funds within the next 3 years to review how leptin is controlled differently in mammals and fish and the resulting consequences.

They received a $250,000 grant in the same organization initially to kick start these studies. The study was led by University of Akron Professor of Biology Dr. Qin Liu.

Liu is a leading expert around the technology that allowed leptin manipulation of the zebrafish.

Leptin continues to be the subject of about 30,000 reports since its discovery back in 1994. The hormone achieved notoriety as it signals towards the brain when it’s time for you to eat.