Hypoallergenic Supplement Promotes Healthy Cells and Tissues - 60 Capsules. Melatonin is a hormone derived from the amino acid tryptophan. Primarily synthesized in your pineal gland, melatonin is released mostly at night to make falling asleep easier. In addition to healthy sleep support, melatonin can help inhibit oxidative stress to promote healthy brain function, immune health and more.