MOOD AND SLEEP SUPPORT: L-Tryptophan can help support mood?? relaxation?? and restful sleep.</br>AN ESSENTIAL AMINO ACID: Tryptophan is an essential amino acid that cannot be synthesized by our bodies.</br>AN IMPORTANT PRECURSOR: L-Tryptophan is a biochemical precursor to serotonin?? melatonin?? and niacin.</br>NO PRESERVATIVES & NO GMO - Nutrissence L-Tryptophan 500mg 200 caps (or 100 servings of 1000mg tryptophane) Contains NO GM