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Source Naturals

Serene Science L-Theanine

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200 mg 60 Tabs
  • Helps support relaxation

  • Suitable for vegetarians

  • 200 mg per tablet
L-Theanine is a unique amino acid found almost exclusively in the tea plant (Camellia sinensis) and is the primary ingredient contributing to the unusual taste of green tea. Animal studies have shown that L-theanine crosses the blood brain barrier, supporting neurotransmitters within the brain. Human studies have shown that taking L-theanine supports natural rest and relaxation.

Product Label

Supplement Facts

Serving Size 1 Tablet

  Amount Per Serving %Daily Value
Calcium 76 mg 8%
L-Theanine 200 mg

†Daily Value not established.

Other ingredients: dibasic calcium phosphate, microcrystalline cellulose, magnesium stearate, stearic acid, silica, modified cellulose gum, and hydroxypropyl cellulose.

Suggested Use: 1 tablet 1 to 2 times daily.

WARNING: Not for use by children or women who are pregnant, may become pregnant, or breastfeeding. If you are taking any antidepressant drugs, such as MAOIs or SSRIs, consult your health care professional before using this product.

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

  • 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.

Terms and Ingredient Definitions

Source Naturals Serene Science L-Theanine Reviews

Summary of Customer Ratings & Reviews

Customer Ratings & Reviews

Serene Science L-Theanine 4.7 5 5 6
The suntheanine version is... supposed to be more bioavailable... That's the only reason for the 4 star review. I got this product at a great price. Theanine is a stable, relaxed kind of thing. A simple soother for your day. Source Naturals has been a dependable brand of consistent quality as well. The 200 mg dosage is nice, if you are accustomed to a higher dose. Means taking less capsules. July 5, 2013
Quality product Competitive price for good brand June 27, 2013
great product I would not be without this product. I have been using it faithfully for 11 yrs now and still swear by it. March 5, 2013
I have a hard time falling and staying asleep, this product has definetly helps. February 22, 2011
Wonderful for focus, alertness without drowsiness! All four of my older grandchildren take this product along with fish oil. Their concentration and focus has improved dramatically and so have their grades in school! They are still all-kid but able to relax. They also sleep better at night. I absolutely recommend this product...and have done so repeatedly to my school children's parents. February 7, 2010
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