Jarrow Formulas L-Tryptophan is a mood balancing supplement that helps support emotional wellbeing and restful sleep through the body's natural conversion of tryptophan into serotonin and melatonin. Jarrow Formulas L-Tryptophan is the essential amino acid the body uses to make serotonin and melatonin, supporting a relaxed mood and a better night's sleep. This reputation for quality comes from Jarrow Formulas, using vegan sources and independent lab testing.

Available Sizes & Variants:

60 vegetarian capsules - convenient daily dose for ongoing mood and sleep support.

Benefits & Features:

• Helps keep mood balanced and restful sleep for everyday calm and resilience.
• The main active ingredient, L-Tryptophan, helps boost serotonin and melatonin.
• Within a GMP certified facility, Jarrow Formulas ensures vegan, non GMO production and independent lab verification, so you get a pure, reliable supplement you can trust.
• Designed for daily use to support a calm mood and easier winding down.
• Supports serotonin and melatonin production.

Jarrow Formulas has long stood for purity and reliability. L-Tryptophan is produced as TryptoPure from vegetable sources, and the vegan, non GMO formula is manufactured in GMP facilities with independent lab verification. That combination of transparency, rigorous testing, and consistent dosing is what keeps customers returning. Some users pair this with n acetylcysteine or a vitamin d supplement for broader wellness, reflecting the brand's philosophy of thoughtful, science backed supplementation.

L-Tryptophan (500 mg), Vegetarian capsule (hydroxypropylmethylcellulose, water), magnesium stearate (vegetable source), cellulose, silicon dioxide.

• GTIN: 790011150565
• Manufacturer: Jarrow Formulas
• Categories: Best SellersJarrow FormulasTryptophan Supplements
• Best buy: 6 - 24 months+

United Kingdom Shipping:

Orders placed by 2pm (Monday to Friday) are dispatched the same day. Orders placed after 2pm will be dispatched the next working day.

Free shipping on orders over £50 to the UK.

Returns: Our products are meant to make you feel healthy and at your best. If you need to return your item, you can do so free of charge within 30 days in the same original and unopened packaging. Subject to T&C's.

Take 1 capsule of Jarrow Formulas L-Tryptophan 500mg on an empty stomach 30 minutes before sleep with water or fruit juice, or as directed by your qualified healthcare professional. Store in a cool, dry place, away from direct sunlight. Keep out of reach of children. Do not take this product if you are on any medications, especially antidepressants, or if you are pregnant or breastfeeding. Consult your qualified healthcare professional before using this product, especially if you are taking any SSRIs (selective serotonin reuptake inhibitors).

Please consult the product packaging for accurate instructions on how to use the product.

The Active Ingredient Is: L-Tryptophan (Essential Amino Acid)

L-Tryptophan is an essential amino acid the body uses to produce serotonin and melatonin, important for mood and sleep regulation.

This product features L-Tryptophan that is vegan, fermentation-derived from plant sources using TryptoPure technology, and analysed to ensure purity and quality.

What Does L-Tryptophan Do?

L-Tryptophan is converted in the body to serotonin and melatonin, contributing to normal mood and sleep quality. This pathway supports relaxation and daily wellbeing, in line with EFSA guidance on amino acid function and sleep regulation.

Dr. Silber of the University of California found that L-Tryptophan is converted to serotonin and melatonin in the body, which plays an important role in supporting a balanced mood and restful sleep.

This product is not intended to diagnose, treat, cure, or prevent any disease.

Welzo chose Jarrow Formulas for this L-Tryptophan supplement because the brand aligns with our strict partner criteria: a well-established reputation for quality manufacturing, ingredient transparency, and regular third‑party verification. Jarrow Formulas is widely recognised in the industry for its commitment to high manufacturing standards and trusted product consistency, making it a reliable choice for amino acid formulations. This credibility is reinforced by their GMP‑compliant facilities and independent lab verification of ingredients, including the TryptoPure L-Tryptophan sourced from vegetable fermentations. Learn more about our quality expectations and how we verify products through our rigorous testing protocols and our expert team of doctors, nurses, and nutritionists.

In our evaluation process, our doctors and nutritionists assessed brand pedigree, sourcing ethics, and manufacturing controls to ensure a durable supply chain and product integrity. This brand’s dedication to vegan, gluten‑free, and non‑GMO formulations, combined with clear ingredient lists, makes it particularly suited for this supplement. The product itself provides 500 mg of L‑Tryptophan per capsule, is gluten‑free and vegan, and emphasises the body’s natural pathways to support mood balance, emotional well‑being, and sleep quality as described in the research into the product.