A study published in the British Medical Journal has found that melatonin supplementation can support DNA damage repair associated with oxidative stress in those who work night shifts.
Notably, the study participants given melatonin supplements prior to periods of day sleep experienced a 1.8x increase in urinary creatinine-adjusted 8-hydroxy-2′-deoxyguanosine (8-OH-dG), which is commonly used as a biomarker for DNA repair.
These results suggest that melatonin supplementation may be particularly beneficial for preventing oxidative stress in individuals working antisocial hours.
According to the study's researchers at the BC Cancer Research Centre (BCCRC), melatonin supplementation in the population could counteract the decrease in oxidative damage repair commonly seen in night shift workers — potentially reducing the demographic’s cancer risk.
The problem with night work
Many modern roles require night work, with many professionals in the healthcare, distribution and security industries working into the early hours of the morning and beyond.
However, the long-term effects of night shift work can be palpable, with individuals experiencing circadian rhythm disruptions, as well as an increased risk of cardiovascular disease, obesity, and mental health issues, according to UCLA Health.
Another common side effect associated with night shift work is a decreased ability to repair oxidative DNA damage, which comes from the suppression of the body’s natural circadian rhythm.
Since the circadian rhythm is driven by the hormone melatonin, researchers at the BCCRC wanted to explore if melatonin supplementation could support the body in fixing DNA damage associated with oxidative stress.
The study
To assess how melatonin supplementation could impact oxidative stress measures in night shift workers, researchers selected 40 participants between the ages of 18 and 50.
The volunteers selected have all been doing at least two consecutive night shifts per week for six months, and have no history of sleep or hormone disorders.
They were then given either a placebo or 3mg of melatonin before commencing in day sleep so researchers could take quantitative urine collection and actigraph measures.
During the study, a near-significant 1.8x increase in blood 8-OH-dG levels was observed, which suggests that melatonin supplementation may facilitate DNA repair.
“The results of this trial suggest that melatonin supplementation may improve oxidative DNA damage repair among night shift workers,” noted the study’s lead author, Dr Umaimah Zanif.
“We believe that these findings warrant larger-scale studies, which should consider the impact of multiple doses, differences in individual absorption of melatonin amongst participants and the effects of long-term supplementation with melatonin,” he concluded.