Overall, clinical data suggest that melatonin supplementation improves sleep and neurotransmission and reduces sundowning in those with Alzheimer’s disease. At a mechanistic level, it may decrease the progression of the disease through its protection of neuronal cells from amyloid-beta, possibly due to the facilitation of its degradation and transport from the brain matter through the glymphatic fluid (1–3). In a small pilot study of elderly patients with a mild cognitive deficit, the ability to remember previously learned items improved, and depression decreased with melatonin (4). A more extensive, longer-term study found that patients with mild cognitive impairment scored better on the Mini-Mental Status Exam and the Sleep Disorders Index when taking melatonin (5). Oxidative stress is one of the leading causes of age-related brain dysfunction by impairing neurogenesis. Thus, researchers are exploring influences on monoamine synthesis, a common target for diseases of the aging brain (6,7), as well as the potential of melatonin as a therapeutic in dementia.
Authors: Deanna Minich, Ph.D., Melanie Henning, ND, Catherine Darley, ND, Mona Fahoum, ND, Corey B. Schuler, DC, James Frame
Reviewer: Peer-review in Nutrients Journal
Last updated: September 22, 2022
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