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

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In Stock
  • 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
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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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Weird dreams

Posted by 5611778108828337788 on May 02, 2016

It took a couple of weeks to feel the benefits of this product but my sleep definately improved and my anxiety was moderately reduced. Had some weird dreams though. Really weird! My son son also found this helped him to sleep during a stressful period at university.

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Better than Rx s'

Posted by Reviewer1948093 on Apr 16, 2016

Cheaper too

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