The "sleep hormone" and common supplement melatonin could be linked to a decreased risk of age-related macular degeneration (AMD).
AMD is a progressive eye condition affecting the macula, a small area near the centre of the retina, and can blur your central vision.
There is no definitive cure for AMD but several treatments can help manage the condition and slow its progression.
A team of researchers from the Case Western Reserve University School of Medicine and the Cole Eye Institute both based in the US looked at the health data of over 200,000 people, some at an early stage of the disease and some without age-related eyesight issues.
They compared people who used melatonin supplements with those who didn't in a peer-reviewed study published in JAMA Opthalmology.
The researchers found that melatonin was associated with a reduced risk of age-related eyesight deterioration in individuals without any decline.
It was also linked to a lower risk of further loss of eyesight in those already experiencing it at an early stage.
Several interesting protective properties
AMD is the leading cause of visual impairment in Europe with approximately 67 million people in the EU being currently affected, according to a 2019 study.
Due to an ageing population, this number is expected to increase by 15 per cent by 2050 as AMD affects people over 50.
The disease occurs when the physiological mechanisms that regulate the proper functioning of the macula are disrupted by either abnormal blood vessel growth or the progressive loss of some retinal cells.
Melatonin has antioxidant, anti-inflammatory, and mitochondrial-protective properties with mitochondria being an essential part of cells.
These properties may counteract the processes that cause AMD, according to the researchers.
Previous studies conducted in vitro and on mice showed promising results. Another study conducted in China also demonstrated that patients treated with melatonin showed less eyesight decline.
Researchers noted that further research is needed to validate the results as other factors could also play a part in the disease such as smoking or access to healthcare.
