Melatonin Shows Promise in Reducing Macular Degeneration Risk

3 min read

June 19, 2024 – In a world where most reach for melatonin to ease restless nights or to conquer jet lag, could these tiny pills hold an unexpected key beyond the realm of sleep? Beyond their reputation as sleep aids, melatonin supplements might harbor a surprising potential: as a remedy for vision damage.

In a study of more than 120,000 people ages 50 or older with no history of age-related macular degeneration – the No. 1 cause of severe vision loss in adults over age 50, with about 1 in 10 Americans impacted – those who took melatonin supplements were less likely to get the condition, according to the research published in JAMA Ophthalmology

There are two types of AMD. Dry AMD – which is the most common – can happen when yellow deposits (called drusen) appear on your macula, or the central area of your retina. If they grow or multiply, your vision could worsen. Wet AMD is the less common, late-stage form of disease that can lead to more rapid vision loss. Shaky blood vessels under your macula can leak blood and other fluid, which can hinder your vision. The leaky blood vessels can also cause scarring, which could lead to permanent vision damage. 

The study also looked at more than 65,000 patients with dry AMD and found that melatonin use was linked to a lower chance that the condition would progress to wet AMD. This effect may stem from melatonin's anti-inflammatory and antioxidative properties, which could potentially halt processes that hinder visual functions, said Rishi P. Singh, MD, an ophthalmologist at Cleveland Clinic Florida.

But experts stress that the findings on melatonin and AMD should be viewed as an association, as the results could also be linked to other factors. For example, cigarette smoking and high blood pressure both raise your risk of AMD. 

“What you would need to do next is have other large cohorts confirm this, and to do so in a way that controls, much more importantly, for cigarette smoking or high blood pressure features that might have accounted for confounding in this,” said Neil Bressler, MD, an ophthalmology professor at Johns Hopkins School of Medicine and editor-in-chief of JAMA Ophthalmology.

So, while melatonin’s therapeutic properties could lead to a lower rate of progression or development of AMD, there is not enough information to classify it as an official treatment, according to Sunir Garg, MD, a spokesperson for the American Academy of Ophthalmology and a professor of ophthalmology at Wills Eye Hospital. 

“People who are concerned about developing AMD should stop smoking; should exercise for 30 minutes at least three times a week; should eat dark green leafy vegetables, as well as foods high in omega-3 fatty acids, three times a week; and should see their ophthalmologist annually after the age of 40,” Garg said. “They should not take supplements such as melatonin for their eye health until we have more information.”

Still, the study results are a step in a promising direction, said Vicki Chan, MD, an ophthalmologist based in Los Angeles. 

“This was a retrospective study, so there is still a lot of work that needs to be done, but this is definitely an exciting finding – as melatonin is widely accessible and could easily be implemented.”