What is Doctor’s Best L-Tryptophan with TryptoPure? Doctor’s Best L-Tryptophan with TryptoPure promotes normal, restful sleep and healthy mood and behavior. L-tryptophan, an essential amino acid, is not synthesized by the body and must be obtained through dietary sources. Doctor’s Best L-Tryptophan contains TryptoPure, a highly purified, pharmaceutical-grade L-tryptophan that meets the purity of both the Japanese Pharmacopeia (JP) and the United States Pharmacopeia (USP). How does it work? L-tryptophan, is an essential building block for protein synthesis. It also functions as a biochemical precursor for serotonin, a neurotransmitter. Serotonin is synthesized from L-tryptophan via tryptophan hydrolase. Serotonin can then be converted into melatonin, a neurohormone via N-acetyltransferase and 5-hydroxyindole-O-methyltransferase. Niacin, Vitamin B3, is also synthesized from L-tryptophan. Tryptophan’s benefit for sleep is due to serotonin production. Serotonin is also required for early brain development, emotional maturation, memory and other cognitive functions, as well as coping with fear and stress, healthy sleep patterns, and healthy mood. Serotonin also is the main source of melatonin, the body’s major sleep hormone. Why should I take Doctor’s Best L-Tryptophan with TryptoPure? Sleep is an absolute necessity for maintaining good health. Adequate quantity and quality of sleep is essential for conserving the body’s energy, for maintaining healthy mood, cognitive function, and for supporting physical functioning in general. Dietary supplementation with tryptophan promotes restful sleep, without unwanted additional effects. Findings from several clinical trials conducted over the past 40 years demonstrate that taking tryptophan at night can shorten the time it takes to fall asleep. Numerous studies have established that healthy mood can depend on the availability of tryptophan. Therefore, supplementing with tryptophan can positively affect mood and behavior. In a double blind, placebo-controlled trial the tryptophan group had significantly better scores for positive mood at the end of the trial period, as compared to the placebo group.