L-Tryptophan 500 MG | GNC

Source Naturals® L-Tryptophan 500 MG


Item # 214426

Product Information



Mood, Relaxation, Sleep*
Dietary Supplement

The essential amino acid L-tryptophan helps support relaxation, restful sleep, and positive mood. It plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and street response and sleep/wake cycles. L-Tryptophan also supports immune functions because it is the body's precursor to the kynurenines that regulate immunity. If needed, L-tryptophan converts to niacin in the body, which supports circulation, a healthy nervous system, the metabolism of food, and the production of hydrochloric acid for the digestive system. Source Naturals L-TRYPTOPHAN is extremely pure and is regularly tested to ensure the highest standards of quality.*

HYPOALLERGENIC: contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.


Nutrition Facts
Serving Size  3 Capsule(s)
Servings Per Container  20

Amount Per Serving     % DV

L-Tryptophan  1.5 g   **
Iron (naturally occurring)  575 mcg   **

** Daily Value (DV) not established.
Other Ingredients
Gelatin (capsule), Microcrystalline Cellulose, Dibasic Calcium Phosphate, Colloidal Silicon Dioxide, Magnesium Stearate
Label (click image to enlarge)

How To Use

If you are pregnant, may become pregnant, breastfeeding, or are taking medicaitons such as SSRIs or MAOIs consult your health care professional before using this product., Keep out of reach of children.
, Do not use if tamper evident seal is broken or missing.
Store in a cool, dry place.
P.O. BOX 2218


4.0 / 5.0
5 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
No good for me
No good for me
August 5, 2018
3 months ago
Great sleep aid
Great sleep aid
March 26, 2015
I take one supplement in the morning and one at night. It helps me sleep well at night and helps my mood during the day. It worked well for me the first night I took it. Sometimes it can leave a bad aftertaste, but I found if I drink enough water this doesn't happen.
August 21, 2014
I take one capsule in the morning and one at night. It helps me sleep well and keeps my mood balanced throughout the day. It worked for me the first night I used it. Sometimes it can leave an aftertaste, but I have found if I drink more water that usually doesn't happen.
August 21, 2014
It actually works as a sleep aid!
This actually works as a sleep aid, promoting both intial sleep (falling asleep) and mainting sleep throught the night. It doesn't leave you groggy in the morning, either. No side effects I can find and it is safer than pure 5-HTP which can cause serotonin syndrome in large dosages. Great product!
November 16, 2013
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What are the ingreidents in L-Tryptophan?
A shopper on Jun 2, 2012
BEST ANSWER: The active ingredients in this supplement are L-Tryptophan and naturally occurring iron. Other ingredients are: gelatin (capsule), microcrystalline cellulose, dibasic calcium phosphate, colloidal silicon dioxide and magnesium stearate.