Science Update

Melatonin Improves Inflammation in Athletes

Fact: Melatonin supplementation improves markers of inflammation and oxidative stress in athletes

Melatonin is an indoleamine with a key role in regulating the neuro-immuno-endocrine system found in all organisms. It’s most often used to support sleep, but an increasing amount of research is demonstrating wide-reaching benefits beyond this traditional application.

Previous research has demonstrated significantly lower melatonin levels in athletes as a result of intense training.

According to a study published last week, melatonin supplementation results in a significant decrease in oxidative stress and inflammatory markers in professional athletes during intense training. The study included 81 participants: 47 soccers players, 19 rowers, and a control group of 15 adults who did not practice sports.

Biomarkers of inflammation (interleukin-6 [IL-6], C-reactive protein [CRP]) and oxidative stress were assessed at baseline and after 30 days of melatonin supplementation. The athletes supplemented with 5 mg of melatonin per day. Two functional tests were used to establish maximum heart rate. Maximum oxygen uptake and lactate concentration in the blood were also measured.

Results showed that melatonin concentration was significantly lower in athletes compared to the control group. Additionally, compared to the control group, the athletes had a significantly higher level of isoprostanes. Soccer players had lower glutathione levels and higher levels of malondialdehyde (MDA) and CRP.

After 30 days of melatonin supplementation there was an increase in serum melatonin levels, a decrease in MDA, isoprostane, IL-6 and CRP levels; there was no change in glutathione. Restful sleep has been associated with lower daytime secretion of IL-6, whereas sleep disturbance has been correlated with increased daytime IL-6 levels. Since melatonin improves the quality of sleep, this may explain the reduced IL-6 and CRP levels in athletes.

Intense training can contribute to oxidative damage and inflammation in muscle tissue especially when the body’s antioxidant defense system is compromised. This study demonstrates that there is an increase in lipid peroxidation and inflammatory markers and a decrease in melatonin associated with strenuous activity. Results showed that melatonin supplementation reduces peroxidation of lipids, modulates inflammatory processes and strengthens the defense mechanisms against oxidative stress induced by intense physical effort.

Melatonin should be considered not just for improving sleep in athletes but also for mitigating damage induced by intense exercise. Other nutritional supplements that may be beneficial to reduce inflammation and oxidative stress secondary to intense training include fish oil, curcumin, and astaxanthin.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS

Source: Czuczejko J, Sieski L, et al. Melatonin supplementation improves oxidative and inflammatory state in the blood of professional athletes during preparatory period for competitions. Free Radic Res. 2019 Jan 16:1-12. doi: 10.1080/10715762.2018.1563688.