Could Melatonin Protect Your Eyes as You Get Older?

Melatonin, a popular supplement touted for helping you get some shut-eye, may also benefit your eyes when you’re awake. According to new research, melatonin may help with a condition called age-related macular degeneration (AMD) in older adults.

The study looked at a large group of people aged 50 and older, including some with nonexudative (dry) AMD and some who didn’t have the condition. People with a history of taking melatonin had a lower risk of developing AMD if they didn’t already have it and a slower progression if they did.

“While this is just one study using retrospective data, I do find the results very exciting, in that this other potential antioxidant, melatonin, could help prevent the progression of macular degeneration as well,” Theodore Leng, MDan associate professor of ophthalmology at Stanford University School of Medicine, told Verywell.

Here’s what experts say about the potential untapped role of melatonin for eye health.

What Is AMD?

Age-related macular degeneration (AMD) is a common progressive eye disease people can get as they get older. It blurs your central vision, which can make it harder to read, drive, and tell objects apart. AMD is the leading cause of vision loss in adults aged 65 and older.

AMD can be either “dry” or “wet.” Dry AMD, the most common type, is caused by the natural thinning of the macula as you age. It typically progresses slowly. The early and intermediate stages of AMD don’t have any symptoms. But once it’s in the later stages, you may notice:

• Blurry vision
• Wiggly or crooked lines in your central vision
• Blank spots
• Trouble seeing in low light
• Colors appear dull

The good news is, if dry AMD is caught early, there are some things you can do to slow the progression:

• Eat a nutritious diet
• Quit smoking
• Exercise regularly
• Get a yearly eye exam
• Take vitamin and mineral supplements with antioxidants

Historically, there have not been many treatment options for late-stage AMD. But recent studies have shown that dietary supplements rich in antioxidants (e.g., vitamin C, vitamin E, lutein, and zeaxanthin), also called the AREDS2 formula, can help slow the progression and preserve central vision for the millions of people living with the disease.

“Taken daily, the AREDS2 formula reduces the risk of progression by 25% in patients with moderate or intermediate-stage AMD. It was also shown to reduce the risk of central vision loss by 19%,” said Leng.

How Can Melatonin Protect Against AMD?

Melatonin not only helps to regulate the circadian rhythm, but also offers antioxidant properties that can help protect against age-related conditions caused by oxidative stress, such as:

• Chronic inflammation
• Dysregulated immune system
• Cognitive decline
• Cardiovascular disease
• Neurodegenerative disease (e.g., Parkinson’s disease, Alzheimer’s disease)

Similar to the vitamins and minerals in the AREDS2 formula, melatonin has anti-inflammatory, antiangiogenic (which means it slows tumor growth), and mitochondrial-protective properties that make it a strong candidate for also potentially slowing the development and progression of dry AMD.

This might be, in part, because the condition is associated with inflammation and the negative consequences of aging.

“As AMD has been shown to be mediated by oxidative damage, choroidal neovascularization, and dysregulated apoptosis in the retina, we hypothesize that melatonin may be able to counteract these key pathological processes and thereby reduce the risks of AMD development and progression,” study author Heejin Jeonga medical student at Case Western Reserve University School of Medicine, told Verywell.

Is Taking Melatonin Long Term Safe?

Melatonin, which the Food and Drug Administration (FDA) classifies as a dietary supplement, is considered safe to take long-term and is not associated with any long-term side effects. However, there are some possible short-term side effects associated with melatonin, such as:

• Sleepiness
• Headache
• Dizziness
• Nausea
• Vivid dreams or nightmares
• Mood changes

While it might be relatively safe to take, more research is needed on the long-term effects of daily melatonin use to determine how well it works over time.

There is no optimal dosage recommendation for daily melatonin use, but approximately 5–6 milligrams per dose has been found to be safe. For the purposes of slowing AMD, the recent study did not control for the dose people consumed, so more research is needed to determine how much is needed to be effective for this purpose.

As always, it’s best to talk to your provider about any supplements or vitamins you’re thinking about taking. If you’re worried about your eye health, your provider can also recommend steps to take to help lower your risk and protect your vision as you age.