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Source Naturals, L-Tryptophan, 500 mg, 120 Tablets

Source Naturals, L-Tryptophan, 500 mg, 120 Tablets

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In Stock
  • Expiration Date: Feb 2021
  • Shipping Weight:
    0.3 lbs
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  • Product Code: SNS-01980
  • UPC Code: 021078019800
  • Package Quantity: 120 Tablets
  • Dimensions:
    2.2 x 2.2 x 4 in, 0.25 lbs
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Product Overview


  • Dietary Supplement
  • Mood, Relaxation, Sleep
  • Non-GMO Validated

The essential amino acid L-tryptophan helps support relaxation, restful sleep, and feeling better. It plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response. 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.

Suggested Use

1 tablet three times daily, between meals and preferably with fruit juice. To support restful sleep, take 3 tablets before bed.

Other Ingredients

Dibasic calcium phosphate, stearic acid, modified cellulose gum, and silica .

Suitable for vegetarians and Hypoallergenic: Contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.


Caution: If you are pregnant, may become pregnant, breastfeeding, or are taking medications such as SSRIs or MAOIs consult your health care professional before using this product.

Store in a cool, dry place.

Do not use if either tamper-evident seal is broken or missing. Keep out of the reach of children.

Supplement Facts
Serving Size: 3 Tablets
Servings Per Container: 40
  Amount Per Serving %DV
Calcium 52 mg 5%
Iron (naturally occurring) 570 mcg 3%
L-Tryptophan 1.5 g
†Daily Value not established.
iHerb Customer Reviews

Great help natural medication

Posted by iHerb Customer on Jun 15, 2017 | Verified Purchase

I have found this product to help me better than prescription my head is clearer I feel better myself Before taking this medication my head was messed up I was depressed I was angry now taking this medication I'm clear and focused

Thanks for your feedback!

Not right for me

Posted by iHerb Customer on May 09, 2017 | Verified Purchase

I am sure this product is a great one however on this occasion it was not the right fit for my needs. I followed the dosage directions and found my symptoms became worse. After the evening dose I encountered stomach cramps and diarrhoea. The next couple of days I adjusted the dose to less but found my sleep was more broken than normal and I had headaches. As such after 4 days adjusting the dosage With no odoriferous results I stopped taking them.

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Posted by 5114824664857767864 on May 08, 2017 | Verified Purchase

Helps me deal with the stresses associated with life and uni! I take three before bed and will fall asleep soon after and wake up well rested. Sometimes I take one in the day if I have a test or something high stress coming up and it assists in making me feel relaxed!

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Posted by 5562698693090674771 on Apr 23, 2017 | Verified Purchase

This has been a lifesaver for me. I've been taking it for 18 months. Has completely lifted my mood. I take one in the morning and two before bed. I've put a friend in to this and she's also experiencing a positive change.

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Great results!

Posted by 5556260112705272163 on Apr 01, 2017 | Verified Purchase

Unbelievable results for my son which was depressed with anxiety.

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