L-Tryptophan powder by BulkSupplements.com is one of the selections of amino acids supplement. L-Tryptophan is an essential amino acid which means the body does produced it and it need to be obtained through food and supplementation, as well as converts it to 5-HTP.* Each serving of this product contains 500mg of L-Tryptophan which is about 1/5 tsp and may need an accurate milligram scale to measure. L-Tryptophan powder, or L-Tryptophan 500mg powder, is pure, clean, and does not contain any fillers, additives and artificial flavors. And this tryptophan supplement, an amino acids supplement, is dairy free, soy free, yeast free, no added sugar. All products by BulkSupplements.com are manufactured according to cGMP Standards to ensure the highest quality for manufacturing, packaging, labeling, and holding operations. We work with a third-party laboratory that test our products at multiple stages during production, from raw material to finished products, and ensures compliance, standards, and consistency.