Magnesium is essential for brain function and heart health and has a calming effect on the nervous system, aiding in the reduction of stress and enhancement of sleep. Magnesium glycinate, specifically, is a highly absorbable form of magnesium that may have a calming effect to improve sleep quality. Studies suggest that magnesium helps decrease cortisol, the stress hormone, which can interfere with sleep, and it also helps muscles relax, which can lead to deeper, more restful sleep.
Reference: Abbasi B, Kimiagar M, Sadeghniiat K, Shirazi MM, Hedayati M, Rashidkhani B. "The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial." Journal of Research in Medical Sciences, 2012.