5-HTP
5-HTP (5-hydroxytryptophan) is an amino acid derivative the body makes from tryptophan on the way to serotonin and melatonin. Supplements are usually made from Griffonia seeds.
Also listed as 5-hydroxytryptophan, HTP, 5HTP
Does it help depression?
A Cochrane review found only two trials, involving 64 people, good enough to analyze. The combined evidence for tryptophan and 5-HTP favored treatment over placebo, but was inconclusive. This is not a reliable estimate for 5-HTP alone. 1
A possible benefit remains uncertain because the usable evidence was small and combined two substances. 1
Could it help poor sleepers?
Thirty older adults in Singapore entered a single-blind trial of 100 mg daily for 12 weeks versus no 5-HTP. Selected sleep measures improved, with the clearest signal among people who slept poorly at baseline. The small trial lacked a placebo control. 2
Early findings in older adults warrant larger placebo-controlled trials. 2
What about appetite?
In a two-week trial, 25 overweight adults with type 2 diabetes were assigned 750 mg daily or placebo; 20 completed it. Reported energy intake fell with 5-HTP. This short experiment cannot establish lasting weight control. 3
A small diabetes trial found reduced food intake; broader and longer-term effects remain open. 3
Effects by health goal
Open an effect to see the studies behind its rating. Bars show the size of the effect; the letter grades the evidence.
Stress & Mood3 effects
Weight Management1 effect
Sleep2 effects
No study is linked to this rating.
No study is linked to this rating.
Women's Hormones1 effect
No study is linked to this rating.
All studies
6 publications are linked to 5-HTP, newest first.