A chemical neurotransmitter produced naturally by your body, 5-HTP boosts production of the neurotransmitter serotonin, which facilitates messaging between nerve cells, and helps regulate mood, appetite, and cognitive function.
5-HTP also regulates our circadian rhythm by producing melatonin, a sleep-regulating chemical.
5-HTP is converted into the amino acid L-Tryptophan in your body to relax you without interfering with cognitive function.
What is 5-HTP?
The amino acid tryptophan in turkey, chicken, potatoes, sunflower seeds, and other foods is converted to 5-HTP when you eat. 
Tryptophan is then synthesized into the neurotransmitter serotonin. By raising serotonin levels, 5-HTP helps regulate mood, sleep, appetite and anxiety. (Think of how relaxed and sleepy you feel after a big turkey dinner, and you’ll have a basic idea of what 5-HTP does.)
Melatonin, SAMe, Vitamin B12 and Vitamin D have mood-regulating properties similar to 5-HTP.  Like melatonin and calcium, 5-HTP is also used to treat insomnia, and it bears similarities to fiber, Vitamin D and zinc for weight loss.
Commercial 5-HTP supplements are manufactured using seeds from the Griffonia simplicifolia, an African plant used for medicinal purposes for thousands of years.
The 5-HTP in seeds from the Griffonia is identical to the 5-HTP produced by your body. It’s available online, from Amazon.com and supplement companies, and in vitamin and health food stores.
An excellent choice for insomnia (for most people) and weight loss (for some people), it may not be the go-to supplement for depression due to producing too much of a good thing serotonin).
Other Names for 5-HTP
5-hydroxytryptophan, Serotonin Precursor, 5-Hydroxy L-Tryptophan
One of the many over-the-counter supplements sold as a natural antidepressant, 5-HTP is much better, long-term, at treating other issues – insomnia, social anxiety, headaches and obesity than depression.
When I take 5-HTP to treat depression, I balance it by using a dopamine-boosting supplement like L-tyrosine.
Taking 5-HTP alone for depression or a sluggish mood depletes dopamine, epinephrine, and norepinephrine. These neurotransmitters, called catecholamines, must be produced in the brain, along with serotonin, to prevent depression from getting worse.
I find 5-HTP is best used for insomnia, due to its serotonin-producing ability. It relaxes you and makes you less anxious in social situations while improving your mood and reducing appetite.
It works fine for awhile, but if you use it consistently (without stacking), it results in serotonin overload. Too much serotonin causes brain fog, depression an