Comparison
5-HTP vs L-Tryptophan
5-HTP
Direct serotonin precursor, one step closer than tryptophan. Sourced from Griffonia simplicifolia seeds.
L-Tryptophan
Essential amino acid precursor to serotonin and melatonin. Used for sleep and mood support.
| Field | 5-HTP | L-Tryptophan |
|---|---|---|
| Category | amino-acid | amino-acid |
| Dose range | 50–200mg | 500–2000mg |
| Half-life | 2h | 2h |
| Onset | – | – |
| Evidence | EVIDENCEB | EVIDENCEB |
| Safety | ●●●○○ | ●●●●● |
| Legal (US) | USOTC | USOTC |
| PubMed refs | 460 | 1700 |
The comparison in plain English
Both produce serotonin, but at different points in the synthesis chain. Tryptophan is the dietary precursor; 5-HTP is one step closer (the rate-limiting step is between them). 5-HTP from supplements comes from Griffonia simplicifolia seeds.
Bottom line
5-HTP raises serotonin more reliably than Tryptophan at lower doses, but the steeper effect carries higher serotonin-syndrome risk if combined with SSRIs, MAOIs, or other serotonergic compounds. Tryptophan is gentler and safer for daily use.
Choose 5-HTP if
You want a milder, broader effect (Tryptophan also feeds the niacin pathway) and lower interaction risk. 500–2000mg evening.
Choose L-Tryptophan if
You want a more direct serotonin lift and you are not on any serotonergic medication. 50–200mg evening. Avoid with SSRIs, MAOIs, triptans.