5-HTP Vitamin Information

5-Hydroxytryptophan is a food supplement sold over-the-counter in the United States. It is marketed as an antidepressant and said to regulate moods, aid sleep and help in weight loss. In "5-HTP: The Natural Way to Overcome Depression, Obesity, and Insomnia," Michael Murray explains that 5-HTP is a naturally derived amino acid and is the precursor of the neurotransmitter serotonin. By increasing the levels of 5-HTP in the body, the levels of serotonin should also increase.

Functions of Serotonin

According to "Basic Neurochemistry: Molecular, Cellular and Medical Aspects," serotonin regulates mood, sleep, appetite, learning and memory. Thus, low levels of serotonin are believed to be a cause of depression, and treatment involves either preventing the breakdown of the neurotransmitter or increasing its levels. According to R.B. Matondo and colleagues, serotonin also acts directly as a growth factor and can stimulate hepatic cellular growth following liver damage. Serotonin taken orally does not cross the blood-brain barrier, so in order to increase its levels, either 5-HTP or tryptophan are taken. Tryptophan forms 5-HTP and the latter forms serotonin. Both 5-HTP and tryptophan can cross the blood-brain barrier.

5-HTP and Depression

In an extensive review paper by E.H. Turner and colleagues from the Portland VA Medical Center, it is reported that while definitive, large-scale studies of efficacy and safety have not yet been conducted for 5-HTP, a number of small studies have reported improvement in depression status following 5-HTP administration. Dosages ranged from 20 mg to 3,250 mg/day, with the majority using 200 to 300 mg per day. Dosing frequency ranged from twice a day to four times a day. Not all studies reported dosages and dosing frequencies. The authors of the review paper conclude that while 5-HTP supplementation does have good potential for depression treatment, further clinical trials should be carried out to investigate its efficacy and safety.

Insomnia and Weight Loss

According to T.C. Birdsall, writing in the "Alternative Medicine Review: in 1998, two small studies have reported that 5-HTP is effective in treating insomnia, especially in improving sleep quality. Bridsall recommends that for treating insomnia, 100 mg to 300mg before bedtime should be taken; higher doses have been reported to cause very vivid dreams or nightmares.

According to a study by C. Cangiano and colleagues from the University of Rome, supplementation with 900 mg per day, spread over three doses, resulted in significant reductions in body weight. This was attributed to a decrease in food intake caused by a decrease in appetite.

Adverse Effects

According to Birdsall, some patients may experience mild nausea when taking 5-HTP supplementation. It is thus recommended to start at a low dose of 50 mg three times daily, and increase the dosage gradually. Moreover, there is a concern that in patients taking anti-depressive drugs, mainly SSRIs and MAOIs, supplementation with 5-HTP may results in excessive levels of serotonin in the body. Excessively high levels can cause a reaction known as serotonin syndrome, which, according to "Davidson's Principles and Practice of Medicine, 21st Edition," is characterized by agitation, loss of coordination and hallucinations. You should therefore consult your physician before starting 5-HTP.