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Source Naturals, L-Tryptophan, 500 mg, 60 Capsules

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Out of Stock — Estimated availability 02/26/2017
  • Shipping Weight:
    0.23 lbs
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  • Product Code: SNS-01984
  • UPC Code: 021078019848
  • Package Quantity: 60 Capsules
  • Dimensions:
    2.4 x 2.4 x 4 in, 0.15 lbs
    Switch to Metric units
  • Due to Japanese Custom’s regulations, a maximum of three bottles per order can be imported into Japan.

Product Overview


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

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 stress 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.

Suggested Use

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

Other Ingredients

Gelatin (capsule), silica, magnesium stearate, dibasic calcium phosphate, and microcrystalline cellulose.

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


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

Store in a cool, dry place.

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.

Supplement Facts
Serving Size: 3 Capsules
Servings Per Container: 20
  Amount Per Serving: % DV
Iron (naturally occurring) 575 mcg 3%
L-Tryptophan 1.5 g
†Daily Value not established.
iHerb Customer Reviews

Tried many things

Posted by 5467881029578642891 on Dec 20, 2016

L-Trytophan works for me and Ive tried many things. I do a little combo with melatonin and I actually sleep. Source naturals is a great brand too.

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Life changing

Posted by 5223579135383264901 on Dec 12, 2016

I haven't slept properly and have suffered from Restless Leg Syndrome since my first daughter was born over ten years ago. I was literally at my wits end when I stumbled across some research on the internet in regards to Trytophan and Melatonin being helpful for sleep and I thought, what have I got to lose?! Honestly within a week I noticed a significant difference, I was sleeping ALL NIGHT! I cannot recommend these products enough, they have given me my life back!!

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Posted by 4655954080848470666 on Dec 01, 2016

A lot of sweet dreams with Tryptophane for me! A super product.

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Posted by 5275053037205054621 on Oct 18, 2016

Yes it's helping with sleep 👍

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miracle worker

Posted by 5357939797508878701 on Oct 13, 2016

I have been using L-Tryptophan for quite a few months now and it not only has been the only thing that can help me sleep. But l never wake up feeling drowsy. There have been no side effects and l am left with a feeling of well being. I will continue to use the product. It is so much better than taking valium and sleeping tablets.

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