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Reviews Home >  Supplements >  Amino Acids >  L-Theanine
Top Rated Product
NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

  How Does L-theanine Work? L-theanine promotes mental and physical relaxation without inducing drowsiness. L-theanine is an amino acid found in green tea that produces relaxing effects in the brain. For centuries, green tea has been used in the Orient for its calming properties. Did You Know? All NSI supplements are packaged in HDPE (High Density Polyethylene) bottles. These bottles keep moisture vapor out, protecting the freshness and integrity of their contents, and are 400% more effective compared other brands currently using PET (Polyethylene Terephthalate) bottles. HDPE bottles do not break as glass can and are also recyclable so we urge you to please recycle them.  

Average Customer Rating: 4.459 out of 5 4.5 out of 5
33 of 37 (89%) customers would recommend this product to a friend.
Product Details

Customer Reviews for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 1 out of 5 1 out of 5
Didn't work for me. :(, April 28, 2009
By JazzyGirl from Jamul, California
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 1 out of 5 1 out of 5
Satisfaction: 1 out of 5 1 out of 5

"With all the reviews I read, I was really looking forward to taking this product. However, it seemed to do the opposite to me. I get bouts of anxiety where my body feels heavy and tense, and my adrenaline feels like it's charging. The L-Theanine gave me just about the same feelings--not good.
I wish I knew if anyone else had the same reaction."

Age: 55-64
Gender: Female
Daily supplement usage: 3-5 supplements daily
Referral source: Self-referred
Reason for usage: Specific health concern
Duration of use: 30-60 days
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Review 2 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 4 out of 5 4 out of 5
Notice a difference, April 16, 2009
By BeWellness from Oakland, CA
Value: 5 out of 5 5 out of 5
Quality: 4 out of 5 4 out of 5
Effectiveness: 4 out of 5 4 out of 5
Satisfaction: 4 out of 5 4 out of 5

"Theanine has been great for keeping me relaxed and focused in stressful situations."

Age: 25-34
Gender: Female
Daily supplement usage: 1-2 supplements daily
Referral source: Self-referred
Reason for usage: Specific health concern
Duration of use: 61-180 days
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Review 3 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 5 out of 5 5 out of 5
Excellent Product, April 16, 2009
By subekauf from Fairfield, CT
Value: 4 out of 5 4 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"I looked for L-Theanine made from Suntheanine because I was told this assured a high quality product. I use it sometimes during the day, but always at bedtime to attain a feeling of well-being ."

Age: 65-74
Gender: Female
Daily supplement usage: 6+ supplements daily
Referral source: Friend
Reason for usage: Enhanced performance
Duration of use: Over 180 days
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Review 4 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Top 500 Contributor Top 500 Contributor
Overall Rating: 5 out of 5 5 out of 5
Calming, March 23, 2009
By NightNurse

"I work the nightshift and sometimes experience insomnia, and mild anxiety. The L-Theanine was very effective in relieving anxiety and helping me sleep without making me drowsy or groggy. Definitely recommend!"

Age: 25-34
Gender: Female
Referral source: Self-referred
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Review 5 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Top 1000 Contributor Top 1000 Contributor
Overall Rating: 4 out of 5 4 out of 5
Not sure I can tell, February 25, 2009
By Sweetwitch from Decatur, IL
Value: 5 out of 5 5 out of 5
Quality: 4 out of 5 4 out of 5
Effectiveness: 4 out of 5 4 out of 5
Satisfaction: 4 out of 5 4 out of 5

"I am sleeping better but other than that I am not sure I can tell if this is working. I will continue the bottle and see"

Age: 45-54
Gender: Female
Daily supplement usage: 6+ supplements daily
Referral source: Other
Reason for usage: Enhanced performance
Duration of use: Less than 30 days
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Review 6 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 1 out of 5 1 out of 5
no appetite, December 29, 2008
By stina2008
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 1 out of 5 1 out of 5

"Works to calm you but I don't enjoy food anymore. I'm hungry but I don't like the food."

Age: 25-34
Gender: Female
Daily supplement usage: 1-2 supplements daily
Referral source: Self-referred
Reason for usage: Specific health concern
Duration of use: Less than 30 days
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Review 7 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Top 1000 Contributor Top 1000 Contributor
Overall Rating: 5 out of 5 5 out of 5
Great stuff, September 25, 2008
By ReggieVonTaintStain from VT
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"I love this stuff. I take it a when I have to do a lot of reading and it really helps me calm down and focus. A great combo that works for me when I have a ton of studying to do is L-theanine, phosphatidylserine, and fish oil. I've never taken more than two in a day and I've never taken it before bed but I heard it can cause irritability and sleeplessness in large doses."

Age: 25-34
Gender: Male
Daily supplement usage: 3-5 supplements daily
Referral source: Self-referred
Reason for usage: Enhanced performance
Duration of use: 30-60 days
2 of 2 people found this review helpful.
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Review 8 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Top 25 Contributor Top 25 Contributor
Overall Rating: 5 out of 5 5 out of 5
August 25, 2008
By pridefc from Indiana
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"GABA is the master anti-anxiety amino acid/neurotransmitter and theanine increases your GABA levels. I feel a lot less anxious and better able to focus due to its effects on dopamine levels. Dopamine increases your ability to focus. Bottom line: relaxed & focused. Great stuff!"

Age: 35-44
Gender: Male
Daily supplement usage: 3-5 supplements daily
Referral source: Self-referred
Reason for usage: Promote overall health
Duration of use: Less than 30 days
3 of 3 people found this review helpful.
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Review 9 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Top 250 Contributor Top 250 Contributor
Overall Rating: 5 out of 5 5 out of 5
Stress Reducer w/o drowsiness, August 24, 2008
By Momm from Ohio
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"I was facing a somewhat stressful vacation with aging parents, and my health store staff recommended taking a combination of theanine and holy basil to combat stress without sleepiness, since much of the vacation involved driving. I found this combination to be very effective, and it made a stressful situation easier to handle."

Age: 45-54
Gender: Female
Daily supplement usage: 3-5 supplements daily
Referral source: Other
Reason for usage: Specific health concern
Duration of use: 30-60 days
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Review 10 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 5 out of 5 5 out of 5
stress free!, July 26, 2008
By lz51009 from IL
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"My chiropactor suggested this for my anxiety. I was sceptical, but wow does it work! I call it my "happy pill"! Non-habit forming, non-drowsy, and the best over-the-counter solution to the every day stresses we all encounter. I take one capsule every morning. Try it; it works!"

Age: 55-64
Gender: Female
Daily supplement usage: 3-5 supplements daily
Referral source: Physician
Reason for usage: Specific health concern
Duration of use: Over 180 days
2 of 2 people found this review helpful.
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Review 11 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 3 out of 5 3 out of 5
June 16, 2008
By maddysranny from Delaware
Value: 4 out of 5 4 out of 5
Quality: 4 out of 5 4 out of 5
Effectiveness: 3 out of 5 3 out of 5
Satisfaction: 4 out of 5 4 out of 5

"it is too soon to evaluate with accuracy, the effectiveness although I do think I am getting some benefit."

Age: 55-64
Gender: Female
Daily supplement usage: 6+ supplements daily
Referral source: Other
Reason for usage: Specific health concern
Duration of use: 30-60 days
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Review 12 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Top 25 Contributor Top 25 Contributor
Overall Rating: 1 out of 5 1 out of 5
its Theanine... but doesn't work, February 4, 2008
By tazman
Value: 1 out of 5 1 out of 5
Quality: 1 out of 5 1 out of 5
Effectiveness: 1 out of 5 1 out of 5
Satisfaction: 1 out of 5 1 out of 5

"The schiff melatonin / theanine product knocks me out ... where regular melatonin does nothing for me... so i figured its the theanine that relaxed me.... but then i tried this product and felt nothing....
so i'm not sure if its the synergistic effect of the theanine and melatonin in the schiff product... or a better theanine in it.... but that product works and this one does not.
also , melatonin boost growth hormone, which is great for burning fat naturally..."

2 of 4 people found this review helpful.
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Review 13 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 5 out of 5 5 out of 5
Excellent Product, February 2, 2008
By STAFFSARGE from MA
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"This product is excellent for increasing your mental alertness, concentration and mental performance without the effects of caffeine. The brand is a high quality brand product and that is why I purchased it. I found it also reduces stress or anxiety while relaxing me and does not make you drowsy. I do not use every day, but on days when I feel I need it. Usually it is 1 capsule every 6-8 hours and I do not use it at night. I have used it when I have to drive for long periods of time. Vitacost offers this at a very good price."

Age: 45-54
Gender: Male
Daily supplement usage: 1-2 supplements daily
Referral source: Other
Reason for usage: Enhanced performance
Duration of use: 30-60 days
4 of 4 people found this review helpful.
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Review 14 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 5 out of 5 5 out of 5
Stress Relief, December 26, 2007
By Sharrecks from Texas
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 4 out of 5 4 out of 5
Satisfaction: 5 out of 5 5 out of 5

"Everything I have tried for stress relief has drugged me. Not L-Theanine, because it is a natural part of protein. It took the edge of the extreme stress that was incapacitating me. It is "just enough relief" without heavy medication. I love it and recommend it highly."

Age: 55-64
Gender: Female
Daily supplement usage: 1-2 supplements daily
Referral source: Physician
Reason for usage: Specific health concern
Duration of use: Over 180 days
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Review 15 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 5 out of 5 5 out of 5
Excellent Product, December 15, 2007
By Libra53 from Seattle, WA

"This product has helped me in a number of ways. I have more energy, I'm less stressed even under stressful conditions and I'm better able to concentrate. I like the fact that NSI products use only high quality nutrients in their products too."

Age: 45-54
Gender: Female
Daily supplement usage: 1-2 supplements daily
Referral source: Self-referred
Reason for usage: Enhanced performance
Duration of use: 30-60 days
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Review 16 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 5 out of 5 5 out of 5
helps me relax, December 15, 2007
By happyh from nm
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"When I feel really anxious or uptignt I take l-theanine and soon feel very relaxed. I often take it before retiring at night. It helps me get a good night's sleep."

Age: 65-74
Gender: Female
Daily supplement usage: 6+ supplements daily
Referral source: Other
Reason for usage: Specific health concern
Duration of use: Over 180 days
1 of 1 people found this review helpful.
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Review 17 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Top 1000 Contributor Top 1000 Contributor
Overall Rating: 5 out of 5 5 out of 5
IT REALLY WORKS, December 12, 2007
By YOUNGGRAMA
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"WHAT A GREAT PRODUCT. IT GIVES ME AN ALERT CALM THROUGH THE DAY AND I FEEL RELAXED WITHOUT DROWSINESS. IT REALLY DOES WHAT IT CLAIMS."

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Review 18 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 5 out of 5 5 out of 5
Relax and Focus, November 12, 2007
By GrandmaM from Greater Houston, TX
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"My grown daughter was stressed over work, kids & exams - to the point where she couldn't remember what she studied. The L-Theanine "relaxes you so you can be yourself" and let her study.
Her son also takes it, and can slow down enough to focus. I can't say enough good things about this product."

Age: 55-64
Gender: Female
Daily supplement usage: 1-2 supplements daily
Referral source: Friend
Reason for usage: Specific health concern
Duration of use: 61-180 days
1 of 1 people found this review helpful.
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Review 19 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 5 out of 5 5 out of 5
Great price and a great product, September 28, 2007
By buddys
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"I am very pleased with the results of this product. I have ordered it a few times and will continue as long as I need it."

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Review 20 for NSI L-Theanine From Suntheanine -- 100 mg - 60 Capsules

Overall Rating: 5 out of 5 5 out of 5
Excellent Product, September 22, 2007
By Hebbybebby
Value: 5 out of 5 5 out of 5
Quality: 5 out of 5 5 out of 5
Effectiveness: 5 out of 5 5 out of 5
Satisfaction: 5 out of 5 5 out of 5

"If you are edgey, prone to anxiety or stressed this product is for you. I was having sleep issues and a lot of restlessness until I tried this product. I can't remember ever feeling this good or this calm! I now have 3 other people placing an order. I am extremely satisfied with the results."

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