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Source Naturals


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500 mg 120 Caps
  • 500 mg L-tryptophan capsules

  • Promotes positive mood

  • Supports relaxation and restful sleep
Source Naturals L-Tryptophan promotes positive mood, relaxation and sleep. This essential amino acid plays a part in the synthesis of melatonin and serotonin, the hormones involved with mood, stress response and sleep/wake cycles. L-Tryptophan also supports the body's immune system. Hypoallergenic: contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, salt, starch, preservatives or artificial color, flavor or fragrance.

Product Label

Supplement Facts

Serving Size 3 Capsules

Servings Per Container 40

  Amount Per Serving % Daily Value
Iron (naturally occurring) 575 mcg 3%
L-Tryptophan 1.5 g

†Daily Value not established.

Other ingredients: gelatin (capsule), dibasic calcium phosphate, microcrystalline cellulose, silica, and magnesium stearate.

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

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


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.

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

Terms and Ingredient Definitions

Source Naturals L-Tryptophan Reviews

Summary of Customer Ratings & Reviews

Customer Ratings & Reviews

L-Tryptophan 5 5 11 13
my favorite Always reliable and consistent quality December 14, 2013
Great Sleep Aide My husband uses it regularly to help him sleep. He's tried other sleeping aides , but this is the only one that has worked for him. December 10, 2013
It helps me fall asleep and have a restful sleep. August 8, 2013
Helpful with relaxation I give L-Tryptophan to my elderly mother and to my teen son, both of whom have sleep issues. It seems to help them relax and fall asleep more quickly at night. June 19, 2013
Excellent product, excellent price This product is outstanding and the price at Swanson's Vitamins is excellent. March 27, 2013
The Best I've Found I am so thrilled to have found this product. It gives me a restful night's sleep, and it is very economical. I simply love it!!! March 13, 2013
Outstanding product This product is outstanding in every way. It definitely has a claming effect. March 4, 2013
EXCELLENT I've used different brands and I finally found one I trust and it works the way it should!! February 15, 2013
Good quality! I've been using this brand of L-tryptophan for a couple of years, and have been completely satisfied. October 21, 2012
This is such a great product, a great blend that really works & the value on Swanson site is fabulous----I pray they continue this offering in this quantity--Is stopping my trips to a competitive "V Shoppe" for the value & convenience of offering this quantity... August 8, 2012
Great, effective product My mom and I both love this product. Helps you get a restful sleep. One awesome add on benefit is if you forget to take it or think you don't need it and then 4am rolls around and you can't sleep, it's fine to take it, you'll at least get a few solid hours and it won't make you drowsy in the morning. March 21, 2012
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