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ING-073Ingredient Research Profile

Sleep & Recovery

5-HTP (5-Hydroxytryptophan)

Also known as: 5-Hydroxytryptophan · Griffonia simplicifolia extract · Oxitriptan

●●○Moderate Evidence

Directly increases serotonin synthesis, bypassing the rate-limited tryptophan conversion step. Improves sleep quality, mood, and appetite satiety with good clinical evidence.

Effective Dose

100–300mg / day

per clinical evidence

Evidence Level

Moderate

Sleep & Recovery

Mechanism

Serotonin precursor (bypasses tryptophan hydroxylase rate-limit)

primary action

Best For

Sleep quality

Mood, Appetite control, Depression

This profile is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications.

What Is 5-HTP (5-Hydroxytryptophan)?

5-HTP is produced in the body from tryptophan and is the immediate precursor to serotonin (5-HT). Unlike tryptophan, 5-HTP crosses the blood-brain barrier very efficiently without competing with other large neutral amino acids. It is extracted commercially from the seeds of Griffonia simplicifolia.

How It Works: The Science

5-HTP is decarboxylated to serotonin by aromatic L-amino acid decarboxylase (AAAD). Serotonin cannot cross the BBB, so peripheral serotonin (from gut or liver) is irrelevant — 5-HTP itself must cross the BBB before conversion. In the brain, elevated serotonin improves mood, reduces appetite, promotes slow-wave sleep, and is converted to melatonin in the pineal gland at night.

Primary Mechanism

Serotonin precursor (bypasses tryptophan hydroxylase rate-limit)

Evidence-Based Benefits

Improves sleep quality and increases deep (SWS) sleep

moderate

Wyatt et al. (2006) — 5-HTP increased slow-wave sleep in healthy volunteers

Reduces depressive symptoms

moderate

Multiple trials (Shaw et al., 2002 Cochrane review) — comparable to some antidepressants in mild-moderate depression

Reduces appetite and caloric intake

moderate

Cangiano et al. (1992) — 750mg/day significantly reduced calorie intake in obese patients

Dosage Guide

Effective Dose

100–300mg / day

100–300mg, 30–45 minutes before bed. Start at 100mg to assess tolerance. Take with a small carbohydrate snack (insulin helps tryptophan/5-HTP CNS uptake). Do not use for more than 12 weeks without a break.

Safety Profile & Side Effects

Do not combine with SSRIs, SNRIs, MAOIs, or tramadol — serotonin syndrome risk. May cause GI upset, especially on an empty stomach. Eosinophilia-myalgia syndrome (EMS) occurred with contaminated tryptophan batches in the 1980s — not directly implicated with 5-HTP, but choose reputable brands.

Who Should (and Shouldn't) Take It

Best for
Sleep qualityMoodAppetite controlDepression
Who it's for

Those with poor sleep quality, mild-to-moderate mood issues, or appetite management challenges. Not a replacement for prescribed antidepressants — discuss with a doctor if currently medicated.

Frequently Asked Questions

What is the recommended dose of 5-HTP (5-Hydroxytryptophan)?

100–300mg, 30–45 minutes before bed. Start at 100mg to assess tolerance. Take with a small carbohydrate snack (insulin helps tryptophan/5-HTP CNS uptake). Do not use for more than 12 weeks without a break.

Is 5-HTP (5-Hydroxytryptophan) safe?

Do not combine with SSRIs, SNRIs, MAOIs, or tramadol — serotonin syndrome risk. May cause GI upset, especially on an empty stomach. Eosinophilia-myalgia syndrome (EMS) occurred with contaminated tryptophan batches in the 1980s — not directly implicated with 5-HTP, but choose reputable brands.

How does 5-HTP (5-Hydroxytryptophan) work?

5-HTP is decarboxylated to serotonin by aromatic L-amino acid decarboxylase (AAAD). Serotonin cannot cross the BBB, so peripheral serotonin (from gut or liver) is irrelevant — 5-HTP itself must cross the BBB before conversion. In the brain, elevated serotonin improves mood, reduces appetite, promotes slow-wave sleep, and is converted to melatonin in the pineal gland at night.

Who should take 5-HTP (5-Hydroxytryptophan)?

Those with poor sleep quality, mild-to-moderate mood issues, or appetite management challenges. Not a replacement for prescribed antidepressants — discuss with a doctor if currently medicated.

Related Ingredients

L-TryptophanMelatoninMagnesium (Glycinate / Malate)GABA (Gamma-Aminobutyric Acid)

Medical Disclaimer

Ingredient profiles are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications. Full disclaimer →