The compound is a natural precursor to a neurotransmitter called serotonin, which helps produce “feel-good” chemicals in the brain and body. The body produces serotonin through a series of chemical steps, starting with the amino acid L-tryptophan. One of the chemicals on the way from transforming L-tryptophan to serotonin is L-5-Hydroxytryptophan.

Many studies into the health benefits of 5-HTP and sleep are based on animal models. A 2018 study looked into the effects of L-5-Hydroxytryptophan and gamma-Aminobutyric acid (GABA) on fruit flies, mice, and rats. The scientists used caffeine to induce sleeplessness, then they administered the GABA/L-5-Hydroxytryptophan combination. They found the combination could induce sleep and appeared to enhance sleep quality and length of sleeping time. Another study found that L-5-Hydroxytryptophan may be beneficial in treating disorders of arousal, such as sleep terrors and sleepwalking.

Taking L-5-Hydroxytryptophan may help promote weight loss or maintain a healthy weight.