howtosupplement
Sleep/Mood/Women

L-Tryptophan

Essential amino acid and serotonin precursor that may improve sleep quality and mood in adults with mild sleep issues.

L-Tryptophan

L-Tryptophan

58
score
C
evidence
Caution
risk

Proven Benefits

01Improves sleep continuity
02Reduces premenstrual mood symptoms
03May shorten sleep latency
04May reduce depressive symptoms
05May improve stress-related mood

Chemical Forms

Recommended
  • L-Tryptophan
Avoid
    Expert Note

    Most studies use plain free-form L-tryptophan, so powder and capsules differ more in convenience than efficacy. There is no clearly superior form; the main quality issue is purity testing, because contaminated tryptophan batches were historically linked to eosinophilia-myalgia syndrome.

    Protocol

    Amount
    1-2 g
    Frequency
    Once daily, usually at bedtime
    When
    30-60 minutes before bed; take away from protein-heavy meals, as competing amino acids can reduce brain uptake.

    Condition-Based Dosing

    First-time or side-effect-prone users
    500 mg at bedtime for 3-7 days, then increase if needed
    Mild sleep support
    1-2 g 30-60 minutes before bed
    Premenstrual mood symptoms
    2-6 g/day during the luteal phase has been studied

    Safety & Limits

    Upper Safe Limit
    No official UL; up to 6 g/day has been used short term in adult trials, but self-use above 2-3 g/day should be clinician-supervised.
    Cycling
    Safe for continuous use

    Contraindications

    SSRIs, SNRIs, MAOIs, triptans, linezolid, or St. John's Wort — additive serotonergic effect; serotonin syndrome risk
    Bipolar disorder — serotonergic agents may worsen mania, agitation, or sleep disruption
    Pregnancy or breastfeeding — insufficient supplemental safety data
    Sedative-hypnotics or regular alcohol use — additive drowsiness and impaired coordination
    Moderate to severe liver or kidney disease — use only with clinician guidance
    Other serotonergic supplements (5-HTP, SAMe) — additive serotonergic effect and higher serotonin syndrome risk

    Synergies

    Vitamin B6

    Vitamin B6 is a cofactor in serotonin synthesis, so low B6 status may limit conversion of tryptophan to downstream neurotransmitters.

    Avoid Combining With

    • ✕High-protein meals around the dose (other large neutral amino acids compete for brain transport)
    • ✕BCAA or EAA supplements taken together (compete for transport into the brain)
    • ✕Alcohol within a few hours of the dose (worsens sedation and can offset sleep benefits)
    Updated Invalid Date