• Each vegetarian capsule delivers 220 mg of L-tryptophan, a free-form amino acid that supports muscle repair and lean-mass goals when paired with diet and training.
• L-tryptophan is a precursor to serotonin and melatonin, helping support mood and sleep.
• Free-form L-tryptophan is absorbed more efficiently than amino acids from protein sources, boosting supplementation effectiveness.
• 90 vegetarian capsules from Natural Factors offer a convenient, plant-based option for amino acid support.
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Natural Factors, L-Tryptophan, 220mg, 90 Vegetarian Capsules
Size
90
vegetarian capsules
UPC
627765028638
Best Before
10/2029
About this item
Suggested Use
Recommended adult dose: 1 capsule daily or as directed by a health care practitioner.
Ingredients
Each vegetarian capsule contains:
L-tryptophan
220
mg
Non-medical Ingredients:
Vegetarian capsule (carbohydrate gum [cellulose], purified water), dicalcium phosphate dihydrate, vegetable grade magnesium stearate (lubricant), microcrystalline cellulose, silica, stearic acid.
Description
Natural Factors L-Tryptophan is a free-form amino acid used as a workout supplement to support muscle repair. L-tryptophan is one of nine essential amino acids, meaning that it cannot be synthesized by the body and must come from the diet. In addition to a healthy, balanced diet and regular resistance training, supplementing with L-tryptophan has been shown to help build lean muscle mass.
L-tryptophan is a fundamental component of proteins and has numerous critical roles throughout the body, such as building and repairing muscle and other tissues, maintaining a healthy immune system, producing hormones, and supplying energy. L-tryptophan is also used to synthesize the neurotransmitter serotonin and the hormone melatonin in the brain, which play important roles in mood and sleep.
Although various protein-rich foods contain L-tryptophan, the process of absorbing and converting it into a usable form is inefficient. As a free-form amino acid, L-tryptophan is more effective than the form obtained directly from food. By working to restore tryptophan levels and protect muscle integrity during strenuous exercise, L-tryptophan encourages the body to metabolize fat.
L-tryptophan is a pharmaceutical-grade, free-form amino acid made through a natural fermentation process. This one-per-day vegetarian capsule is an excellent option for anyone who wants extra nutritional support for their active lifestyle.
- Helps build lean muscle mass
- Provides athletic support
- Used as a workout supplement for muscle recovery
- Provides a highly usable form of the essential amino acid L-tryptophan
- Supplies a precursor for serotonin and melatonin
- Contributes to protein synthesis
Frequently Asked Questions
What is Natural Factors, and is it a trustworthy supplement brand?
Natural Factors is a Canadian-owned supplement manufacturer founded in 1948 and headquartered in Coquitlam, British Columbia. One of North America's largest supplement makers, it operates over 1,000 acres of certified organic farmland in BC's Okanagan Valley and manufactures in-house at Health Canada-licensed, FDA-inspected facilities. Every product is third-party tested through ISURA for over 800 contaminants including pesticides and heavy metals. Natural Factors is also B Corp certified, meeting rigorous environmental and social standards.
What is Natural Factors and is it a reliable Canadian supplement brand?
Natural Factors is one of Canada's largest supplement manufacturers, founded in 1955 by Jack and Rona Katz in British Columbia and still 100% Canadian family-owned. The company controls every production stage from raw material sourcing to finished product. Its facility holds TGA certification from Australia's Therapeutic Goods Administration, one of the world's strictest supplement manufacturing standards. All products are ISURA certified — independently tested for 800+ contaminants including pesticides and heavy metals — and Natural Factors conducts four rounds of product testing, double the industry average of two.
What sets Natural Factors apart from other supplement brands?
Natural Factors' most distinctive quality is vertical integration: the company grows its own raw herbs on 1,000+ acres of certified organic farmland in BC's Okanagan Valley, then processes and manufactures in-house. Most supplement brands source raw materials from external suppliers with no direct agricultural control. Natural Factors also uses ISURA third-party testing, a Canadian standard that screens for over 800 contaminants, well beyond typical heavy-metal panels. B Corp certification further reflects a documented commitment to environmental and social accountability, not just a marketing claim.
What makes Natural Factors different from other Canadian supplement manufacturers?
Natural Factors holds TGA certification from Australia's Therapeutic Goods Administration — one of the world's most rigorous pharmaceutical manufacturing standards, rarely earned by Canadian brands and far exceeding most North American certification requirements. Its ISURA testing program screens every product for 800+ contaminants, and it conducts four rounds of quality testing per product versus the industry standard of two. The company also operates its own farm in the Okanagan Valley for select botanical ingredients — a level of vertical integration uncommon among supplement manufacturers — and has been family-owned for over 70 years.
The information provided above is for reference purposes only and has not been reviewed or approved by Health Canada. It does not constitute medical advice and should not replace consultation with a qualified healthcare professional.
Caution
Consult a health care practitioner prior to use if you are pregnant or breastfeeding. Keep out of the reach of children.
Disclaimer
You should not use the information or services on this Site to diagnose or treat any health issues or for prescription of any medication or other treatment.
Always check the product label or packaging prior to using any product. If there are discrepancies, customers should follow the information provided on the product label or packaging.
Natural Factors, L-Tryptophan, 220mg, 90 Vegetarian Capsules
Size
90
vegetarian capsules
UPC
627765028638
Best Before
10/2029
$17.99
Quantity
Not enough inventory in stock
Purchase limit exceeded
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In stock at LIFEPLUS Natural Health
#1825 - 4720 Mcclelland Rd, Richmond, BC
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Today, Sep 15
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