5-HTP
Amino Acid ·Exploratory record · not publication-reviewed ·Updated July 13, 2026
Direct precursor to serotonin, bypassing the rate-limiting tryptophan hydroxylase step. Effective for mood, sleep, and appetite regulation.
Exploratory record, not a reviewed medical publication.
See the editorial and medical-review policies for the publication gate.
This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.
What the research says.
A quick, data-only summary. The full evidence, dosing, and sources are below.
5-HTP is an amino acid most often used for mood support, sleep quality, appetite control. NutriStack rates the overall evidence as moderate. A typical adult dose is 50–200 mg daily, commonly taken as 5-htp from griffonia simplicifolia seed extract. This profile indexes 17 sources.
The bottom line
Evidence rating moderate. Most-documented uses: mood support, sleep quality, appetite control. 17 sources indexed (1987–2025), with 0 interaction records on file.
How it works, mechanistically.
Core mechanism
Converted directly to serotonin (5-HT) by aromatic L-amino acid decarboxylase. Unlike tryptophan, does not require tryptophan hydroxylase and is not diverted to kynurenine pathway. Serotonin is then converted to melatonin in the pineal gland.4,14
Dosing & protocol.
Take on empty stomach for best brain uptake. Evening dosing for sleep; morning for mood.14,3
What it actually costs.
Real-world pricing across three quality tiers. Assumes Griffonia Seed Extract.
Assumes 50-200 mg/day. Vendor basis: BulkSupplements powder, NOW/iHerb capsules, Vitacost, and Life Extension; premium reflects higher per-capsule specialty pricing. Updated 2026-05-28.
The same dose, as food.
How much you'd eat to match a supplemental dose.
5-HTP is not meaningfully present in common foods; it is typically extracted from Griffonia simplicifolia seeds, which are not a normal dietary food.
Full safety detail.
Sources, by evidence tier.
Numbered references. Citations throughout the page link here.
Meta-analyses & systematic reviews
2- 1Effects of 5-hydroxytryptophan on distinct types of depression: a systematic review and meta-analysisPMIDJavelle F et al. · Nutr Rev · 2020
Meta-analysis of 7 studies showed depression remission rate of 0.65 (95% CI: 0.55-0.78) with large effect size (Hedges g = 1.11).
- 2Tryptophan and 5-hydroxytryptophan for depressionPMIDShaw K et al. · Cochrane Database Syst Rev · 2002
5-HTP and tryptophan were better than placebo at alleviating depression (Peto OR = 4.1), though small study sizes limit conclusions.
Randomized controlled trials
8- 3The Impact of 5-Hydroxytryptophan Supplementation on Cognitive Function and Mood in Singapore Older Adults: A Randomized Controlled TrialPMIDLi S, Sutanto CN, Xia X et al. · Nutrients · 2025
Li S, Sutanto CN, Xia X et al.. The Impact of 5-Hydroxytryptophan Supplementation on Cognitive Function and Mood in Singapore Older Adults: A Randomized Controlled Trial. Nutrients. 2025
- 4Intravenous infusion of 5-hydroxytryptophan to mid-lactation Holstein cows transiently affects milk production and circulating amino acid concentrationsPMIDPszczolkowski VL, Connelly MK, Hoppman A et al. · Journal of dairy science · 2024
Pszczolkowski VL, Connelly MK, Hoppman A et al.. Intravenous infusion of 5-hydroxytryptophan to mid-lactation Holstein cows transiently affects milk production and circulating amino acid concentrations. Journal of dairy science. 2024
- 5The Effects of 5-HTP on Body Composition: An 8-Week Preliminary RCTPMIDMeloni M et al. · Int J Environ Res Public Health · 2022
Fat mass decreased significantly in 5-HTP group (p=0.02) but not placebo, with significant between-group differences (p=0.048).
- 6Tryptophan-enriched diet or 5-hydroxytryptophan supplementation given in a randomized controlled trial impacts social cognition on a neural and behavioral levelPMIDZamoscik V, Schmidt SNL, Bravo R et al. · Scientific reports · 2021
Zamoscik V, Schmidt SNL, Bravo R et al.. Tryptophan-enriched diet or 5-hydroxytryptophan supplementation given in a randomized controlled trial impacts social cognition on a neural and behavioral level. Scientific reports. 2021
- 7Placebo-controlled comparison of three dose-regimens of 5-hydroxytryptophan challenge test in healthy volunteersPMIDGijsman HJ, van Gerven JM, de Kam ML et al. · Journal of clinical psychopharmacology · 2002
Gijsman HJ, van Gerven JM, de Kam ML et al.. Placebo-controlled comparison of three dose-regimens of 5-hydroxytryptophan challenge test in healthy volunteers. Journal of clinical psychopharmacology. 2002
- 8Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophanPMIDCangiano C et al. · Am J Clin Nutr · 1992
Double-blind RCT in 20 obese patients: 5-HTP (900 mg/d) produced significant weight loss with reduced carbohydrate intake and early satiety.
- 9Double-blind study of 5-hydroxytryptophan versus placebo in the treatment of primary fibromyalgia syndromeSource linkedPMIDCaruso I, Sarzi Puttini P, Cazzola M, Azzolini V · J Int Med Res · 1990
- 105-Hydroxytryptophan: a review of its antidepressant efficacy and adverse effectsPMIDByerley WF, Judd LL, Reimherr FW et al. · Journal of clinical psychopharmacology · 1987
Byerley WF, Judd LL, Reimherr FW et al.. 5-Hydroxytryptophan: a review of its antidepressant efficacy and adverse effects. Journal of clinical psychopharmacology. 1987
Reviews & position papers
5- 11Detection of melatonin and 5-HTP in dietary supplements based on multiple spectraPMIDYang H, Zhang X, Gao Y et al. · Frontiers in nutrition · 2025
Yang H, Zhang X, Gao Y et al.. Detection of melatonin and 5-HTP in dietary supplements based on multiple spectra. Frontiers in nutrition. 2025
- 125-Hydroxytryptophan toxicity successfully treated by haemodialysis in a dogPMIDArbona DV, Cowgill LD, Press S et al. · Veterinary medicine and science · 2023
Arbona DV, Cowgill LD, Press S et al.. 5-Hydroxytryptophan toxicity successfully treated by haemodialysis in a dog. Veterinary medicine and science. 2023
- 135-HTP efficacy and contraindicationsPMIDBirdsall TC · Altern Med Rev · 2012
Comprehensive review of 5-HTP safety including emphasis on serotonin syndrome risk with SSRIs and eosinophilia myalgia syndrome concerns.
- 14Serotonin a la carte: supplementation with the serotonin precursor 5-hydroxytryptophanPMIDTurner EH et al. · Pharmacol Ther · 2006
5-HTP bypasses the rate-limiting tryptophan hydroxylase step to directly increase serotonin; relatively few adverse effects at therapeutic doses.
- 155-Hydroxytryptophan: a clinically-effective serotonin precursorSource linkedPMIDBirdsall TC · Alternative medicine review : a journal of clinical therapeutic · 1998
Reference material
2- 16Sutanto CN, Xia X, Heng CW et al.. The impact of 5-hydroxytryptophan supplementation on sleep quality and gut microbiota composition in older adults: A randomized controlled trial. Clinical nutrition (Edinburgh, Scotland). 2024Source linkedPMID
- 17Truyens M, Lobatón T, Ferrante M et al.. Effect of 5-Hydroxytryptophan on Fatigue in Quiescent Inflammatory Bowel Disease: A Randomized Controlled Trial. Gastroenterology. 2022Source linkedPMID
Common questions.
Quick answers about 5-HTP, drawn from the data on this page.
What is 5-HTP?
Direct precursor to serotonin, bypassing the rate-limiting tryptophan hydroxylase step. Effective for mood, sleep, and appetite regulation.
What is 5-HTP used for?
Commonly cited benefits of 5-HTP include: Mood support; Sleep quality; Appetite control; Anxiety reduction; Migraine prevention. NutriStack rates the overall evidence as moderate.
What is a typical dose of 5-HTP?
A typical adult dose of 5-HTP is 50–200 mg daily. The commonly recommended form is 5-HTP from Griffonia simplicifolia seed extract. These are general ranges, not personalized advice; confirm the right dose with a clinician.
What are the side effects of 5-HTP?
Reported side effects include nausea, gi upset, drowsiness, vivid dreams. This is educational information; check with a healthcare professional before use.
How strong is the evidence for 5-HTP?
NutriStack rates this as Moderate, meaning several aligned RCTs or one large RCT plus supporting reviews. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.
Use this with your stack
5-HTP in NutriStack.
Add it to your stack, see how it interacts with everything else you take, and get a Stack Score that updates the moment it does.