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

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In Stock
  • Expiration Date: Nov 2019
  • Shipping Weight: 0.3 lbs (0.14 kg)
  • Product Code: SNS-01980
  • UPC Code: 021078019800
  • Package Quantity: 120 Tablets
  • Dimensions: 2.2 x 2.2 x 4 in, 0.25 lbs (0.11 kg)
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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


Posted by 4652955998457969064 on Jul 16, 2016

These tablets are fantastic if you are having trouble sleeping. I recently lost my son and couldn't sleep but these made me relax and had a great sleep with no after effects, highly recommend them.

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Great stuff :)

Posted by 4803412722445604090 on Jul 02, 2016

I take this every night to get to sleep. Before using this I couldn't get to sleep & would be awake till 3am. Highly recommended!

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Posted by 4665368661407529820 on May 30, 2016

Helping me thanks, very happy.

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They work but space you out the next day

Posted by 5375783669111175622 on May 12, 2016

Take as instructed. They work but I feel off the next morning. Won't finish the bottle for that reason.

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완전 푹 자요 for sound sleep

Posted by Reviewer1117455 on May 03, 2016

샤오미 미밴드 사용하면서 수면패턴측정하는데 deep sleep light sleep 구분할정도로 아주 미세하고 진짜 측정 정확하다 싶었는데 이거 복용한 날은 미밴드가 sleep data를 감지 못할정도로 시체처럼 자나봐요 자고 나면 푹잔 느낌입니다. 그래도 최소 6시간은 자야 개운하지 중간에 깨면 더 졸리더라구요.

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