A new Canadian study suggests melatonin, the sleep-regulating hormone, may aid in repairing DNA damage caused by years of poor sleep. Beyond its role in sleep, melatonin is a powerful antioxidant, and researchers believe it could enhance the body’s natural repair mechanisms.

The study involved 40 night-shift workers who took either a 3mg melatonin supplement or a placebo before their daytime sleep. Scientists measured DNA repair activity by analyzing levels of 8-hydroxy-2′-deoxyguanosine (8-OH-dG) in urine samples—a marker indicating successful removal of damaged DNA.

Participants who took melatonin showed an 80% increase in urinary 8-OH-dG levels during daytime sleep, suggesting enhanced DNA repair. However, this effect was not observed during their subsequent night shifts when natural melatonin levels were lower. Researchers noted that while the findings were “borderline statistically significant,” they align with earlier studies linking melatonin to DNA repair genes.

The results indicate melatonin may help the body recognize and remove damaged DNA segments, potentially reducing long-term health risks associated with sleep disruption. While it doesn’t erase years of accumulated damage, melatonin could boost the body’s repair capacity for those with chronic sleep disturbances, such as shift workers or insomniacs.

Melatonin supplements, widely used to regulate sleep patterns, are prescription-only in the UK. This study suggests their benefits may extend beyond sleep, playing a role in DNA health. However, melatonin is not a cure-all—good sleep hygiene, nutrition, and exercise remain key to protecting cellular health.

This research strengthens the connection between sleep and overall well-being, hinting that improving sleep quality—potentially with melatonin—could be a crucial factor in long-term health maintenance.