Amino acid
Tryptophan
Tryptophan is an essential amino acid found in protein foods, which the body uses to make serotonin, melatonin and niacin.
Also listed as L-Tryptophan
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.
Sleep2 effects
The impact of tryptophan supplementation on sleep quality: a systematic review, meta-analysis, and meta-regression.2021The Impact of Tryptophan Supplementation on Sleep Quality: A Systematic Review, Meta-Analysis and Meta-Regression2021Evaluation of l-tryptophan for treatment of insomnia: A review2004
No study is linked to this rating.
Essential Health1 effect
No study is linked to this rating.
Stress & Mood4 effects
No study is linked to this rating.
No study is linked to this rating.
Cognition1 effect
No study is linked to this rating.
All studies
3 publications are linked to Tryptophan, newest first.
The impact of tryptophan supplementation on sleep quality: a systematic review, meta-analysis, and meta-regression.2021The Impact of Tryptophan Supplementation on Sleep Quality: A Systematic Review, Meta-Analysis and Meta-Regression2021Evaluation of l-tryptophan for treatment of insomnia: A review2004