What Is 5-HTP?
5-HTP, or 5-hydroxytryptophan, is an amino acid that our body produces from a dietary amino acid called l-tryptophan. It has the ability to be converted into the mood-regulating neurotransmitter serotonin as well as the sleep-inducing hormone melatonin. 
5-HTP may also be synthesized in the laboratory by extracting it from the seeds of the plant Griffonia simplicifolia.
How Does It Work?
Although l-tryptophan can be obtained by eating foods that contain it, such as red meat and turkey, its ability to be converted into 5-HTP - and ultimately into serotonin - is limited by the availability of an enzyme called tryptophan hydroxylase. Tryptophan hydroxylase can be inhibited by many different factors, such as stress, insulin resistance, vitamin B6 deficiency, and magnesium deficiency. Supplementing with 5-HTP overcomes this problem by eliminating the need to convert l-tryptophan to 5-HTP, thus allowing more 5-HTP to be available for conversion to serotonin.
Does 5-HTP Help with Depression?
5-HTP supplements are thought to treat depression by increasing serotonin levels. In fact, several small studies have found that 5-HTP reduced symptoms of depression.
How Much 5-HTP Should I Take for Depression?
Doses of around 200 to 300 mg per day of 5-HTP seem to be fairly well-tolerated. The most common side effects reported with 5-HTP include nausea, vomiting, and diarrhea.
