L-Tryptophan - 90 Capsules

L-Tryptophan is the essential amino acid from which the body synthesizes serotonin and melatonin – the key neurotransmitters for mood, well-being, and sleep. Under chronic stress, tryptophan is degraded via the kynurenine pathway, which lowers serotonin levels.

Benefits: Promotes serotonin and melatonin synthesis · Supports balanced mood · Improves sleep quality · Helps with stress-related insomnia

Ships from Germany · Vegan ✓ · No added sugar ✓ · GMO-free ✓ · HACCP-compliant

Scientific Background – Based on publicly available research literature. Intended for general information only and does not replace medical advice.

• Metabolic Pathway: L-Tryptophan → 5-Hydroxytryptophan (5-HTP) → Serotonin (5-HT) → Melatonin. This synthesis pathway occurs, among other places, in the brain and requires the active transport of L-tryptophan across the blood-brain barrier – in direct competition with other large neutral amino acids (BCAA, phenylalanine).
• Kynurenine Competition Under Stress: Chronic stress, via cortisol, activates the enzyme indoleamine-2,3-dioxygenase (IDO), which converts tryptophan into kynurenine (instead of serotonin). This mechanism is an established biological model for stress-induced depressive symptoms.
• Clinical Evidence: A Cochrane analysis (Shaw et al., 2002) showed moderate but preliminary evidence for the efficacy of 5-HTP and L-tryptophan in depressive mood; the quality of the studies was rated as limited.
• Dosage: In clinical studies, 500–2,000 mg/day were used; higher doses do not necessarily show stronger effects.
• ⚠️ Important Safety Note: L-Tryptophan should not be taken with MAO inhibitors, SSRIs, SNRIs, or other serotonergic substances – risk of serotonin syndrome (life-threatening). Always consult a doctor for psychiatric conditions or when taking medication.