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Swanson Ultra

Double Potency Suntheanine L-Theanine

Swanson $12.99
Retail $23.49
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Veg Caps Size:
1, Pill Size Guide
200 mg 60 Veg Caps

"Theanine is one of the few supplements I can take to relax, and even help my sleep. I like this dosage and the price, and it works well." ~product review by Babble

  • Double potency L-theanine supplement

  • Delivers 200 mg per capsule, an important amount supported by clinical research

  • Promotes calm, balanced mental health and emotional well-being

L-theanine is an amino acid found almost exclusively in tea plants and, in particular, green tea. The pioneers at Taiyo International discovered that the relaxing properties of green tea may be tied to this unique nutrient and developed Suntheanine through a patented, all-natural process designed to amplify its calming potential. Research indicates that Suntheanine stimulates alpha wave activity in the brain, which is associated with calm alertness. Our new Double Potency Suntheanine L-Theanine delivers 200 mg per capsule, the upper limit shown to produce results in clinical research.

Product Label

Supplement Facts

Serving Size 1 Veggie Capsule

  Amount Per Serving % Daily Value
Suntheanine® L-Theanine 200 mg *

*Daily Value not established.

Other ingredients: Brown rice flour, hypromellose (vegetable capsule), may contain one or both of the following: magnesium stearate, silica.

Suggested Use: As a dietary supplement, take one veggie capsule per day with water before meals.

Suntheanine® is a registered trademark of Taiyo International, Inc.

Terms and Ingredient Definitions

Swanson Ultra Double Potency Suntheanine L-Theanine Reviews

Summary of Customer Ratings & Reviews

Customer Ratings & Reviews

Double Potency Suntheanine L-Theanine 4.4 5 16 16
Suntheanine L-Theniane I started using it just two weeks ago to help with my sleep and even though I still wake up during the night, it's less frequent and I sleep more deeply. Quite happy with the product. April 2, 2014
peace and calm This product works. I am left feeling calmer and more relaxed after using L-theanine. February 4, 2014
Comfort This really enables me to be relaxed and comfortable. It is important for my sense of well-being; better than deep breathing! December 22, 2013
Good theanine/good price Theanine is one of the few supplements I can take to relax, and even help my sleep. I like this dosage and the price, and it works well. November 18, 2013
Excellent value! I am amazed at the quality and efficiency of Swanson's L-Theanine! For a product of this high quality, I would be prepared to pay three times this amount, but Swanson's keeps so many of their products at such affordable prices! I have a very high-pressure lifestyle, and this supplement helps me deal with the intense pressures and I can leave those pressures behind at the end of the day. I find it much easier to relax and enjoy 'My Time'. Thank you Swanson's! November 17, 2013
Too strong! Had to stop taking these. 200 mg. too strong for me. 100 is better. November 17, 2013
The cheapest Having done the research intensively, I think this is the cheapest legit L-theanine in existence --- "Swanson Ultra Double Potency Suntheanine L-Theanine". If you already know L-theanine is what you need, this is the end of your search for a safe bargain! October 25, 2013
Easy to swallow I like the 200 mg dosage of the Suntheanine because I get the recommended amount in just one capsule instead of the usual two. I am also happy with the price. Suntheanine helps me breeze through stress. Thanks for a great product. October 23, 2013
Suntheanine L-Theanine I purchased this for my daughter after going through a divorce.She hasn't said anything about it, but to me she seems more calm. October 19, 2013
Double Potency Suntheanine L-Theanine I had been ordering L-Theanine from another site and came across it on Swanson's website. The price of it was 1/3 less than where I had been purchasing it. I take just one at night to help make it easier for me to sleep. I will continue to purchase this from Swanson. September 7, 2013
Good for lower-dose requirement This is a good-quality formulation of L-Theanine, just not the intensity that I needed. I recommend this to people who have the need for the basic properties of L-Theanine without extenuating circumstances. September 2, 2013
Sometimes you need a blend I tried taking this without feeling any results. It may work for someone who only needs this one missing supplement. I ended up going with something else sold on Swanson (Theanine Serene with Relora) which worked really well for me. If this doesn't work for you, maybe try this other one. It is pricey, but it works well. August 28, 2013
really helping me! A friend recommended I try this to treat my anger and irritability and general PMS moodiness. So I tried it, taking it 2-3 times daily. After several days, I started to feel like I was on an endorphine high, feeling really good! I feel happier, less frazzled and ready to snap. My anger is very cut down, and I can be a lot more patient and tolerate a lot more frustration. I've had a few relapses of anger, but I think overall it is really helping me, I'm glad I found it! August 21, 2013
It works I have struggled for years with not being able to focus during stressful times and sleeping at night. L-Theanine has done the trick. I like that I can take it only when I want or need it. July 29, 2013
Did not work for me. I have trouble sleeping and hoped that this product would help. Unfortunately, I saw absolutely no difference. I even tried taking triple the recommended dosage to no avail. July 26, 2013
Great value and product The Theanine I was buying was from NOW FOODS and there 200 mg one was expensive. This version is same dosage and cheaper, so this is awesome. It does a lot, and does what it says it does. July 25, 2013
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