The Brain and Melatonin: Benefits Beyond Sleep and Jet Lag
The most common uses of melatonin as a dietary supplement is to support sleep and ease jet lag. Numerous studies have shown that melatonin can help synchronize the circadian rhythms to support the quantity and quality of sleep. While these applications are important, a fascinating connection between melatonin and cognition and mood is emerging in the scientific literature.
As an antioxidant, melatonin inhibits nitric oxide synthase, which produces the free radical nitric oxide. Melatonin also contributes to the stimulation of other antioxidant enzymes including glutathione. An important aspect regarding melatonin is that it readily passes through the blood-brain-barrier and can accumulate in the central nervous system. As a result, studies have shown that melatonin can help support both cognition and mood.
A 2015 study featured in The Journal of Clinical Endocrinology & Metabolism featured a cohort of 1,105 elderly individuals with an average age of 71.8. Markers of cognition and mood were measured against melatonin levels, which have a tendency to decline with age. In this study, the higher the melatonin levels, the lower the prevalence of cognitive decline and depressed mood.
A 2013 review featured in the Journal of Neurology & Neurophysiology found that melatonin improved sleep quality, cognitive performance, memory, and depressive symptoms in patients with mild cognitive decline. This is consistent with a review done in 2010. A 2008 study also achieved similar results by using a combination of 2.5 mg of melatonin in combination with light therapy.
While melatonin is typically used to support sleep, it appears it can also help support brain function and mood. This is significant because studies show that some of the common prescription and over-the-counter sleep medications can actually negatively impact cognition over time. In addition, melatonin is considered safe for long-term use. One group of researchers concluded, “Exogenous melatonin supplementation is well tolerated and has no obvious short- or long-term adverse effects.”
Melatonin is available as a dietary supplement in a variety of forms and dosages.
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