Suntheanine® SR is a dietary supplement featuring patented Suntheanine® SR and formulated to support calmness, mental clarity and cognitive function. The SmartMatrix™ sustained-release tablet releases L-theanine gradually - over 6 to 8 hours - for both immediate and long-lasting support.*
Easy-to-swallow tablets
No salt, sugar, starch, artificial flavors, colors, sweeteners or preservatives
Gluten-free
Vegan/Vegetarian
Free of common allergens (milk, egg, fish, shellfish, soy, peanuts, tree nuts and wheat)
Sustained-release
SmartMatrix™ is a trademark of Innovite, Inc.
Suntheanine® is a registered trademark of Taiyo International, Inc
Suntheanine® SR is specially formulated with SmartMatrix™ sustained-release tablet technology to gradually deliver L-theanine over several hours. The tablet releases up to 40% quickly for immediate support, while the remaining 60% is released slowly to provide longer-lasting effects.*
Since Suntheanine® SR has a similar structure to glutamate and can bind to glutamate receptors in the brain, researchers believe this is the main action responsible for its ability to help the body manage stress and reduce its negative effects.
After ingestion, L-theanine has the ability to cross the blood-brain barrier from 30 minutes up to 5 hours. In the brain, L-theanine is reported to exert its calming effect by several actions. For example:
Modulating neurotransmitter activity: Suntheanine® SR may influence the transport and activity of glutamine and glutamate, key neurotransmitters involved in mental alertness and calmness.
Interacting with brain receptors: Suntheanine® SR can interact with certain glutamate receptors in the brain, which may help promote a calm and relaxed mental state.
Supporting the growth of new brain cells: Suntheanine® SR may help support neurogenesis. Stress can reduce the growth of new brain cells, but L-theanine has been shown to help support neurogenesis.
Suggested Use: As a dietary supplement for adults, take one (1) tablet daily with food or as directed by your healthcare professional.
Clean Formulas
No Preservatives
Gluten-free
Vegan Options
No Artificial Flavors
Promotes Calm, Relaxation. Randomized, double-blind, placebo-controlled trials indicate L-Theanine helps reduce stress and promotes a positive mood. Effective amounts include both a single dose (200 mg) (3,4) and 200-400 mg/day for up to 4 weeks (5-7).
Supports Cognitive Function. Randomized, placebo-controlled clinical trials indicate a single dose of L-theanine (100-200 mg) supports optimal cognitive function in healthy adults, including promoting optimal reaction times in attention tasks in healthy young adults (8); visual attention and reaction time in healthy adults under stress (9); and attention, working memory, and executive function in middle-aged and older adults (10).
Promotes Sleep Quality. A meta-analysis of 18 clinical trials found L-theanine promotes overall sleep quality, including the ability to fall asleep quickly and reduced daytime sleepiness. Most studies used 100-400mg/day, most often 200 mg/day. L-Theanine was typically taken 30-60 minutes before bedtime, either as a single dose or daily for several weeks(11)
Suntheanine® L-Theanine
High Purity. The patented fermentation process yields no less than 98% L-isomer, ensuring a reliable and effective standardized ingredient. Robust Research Portfolio. Supported by extensive research, including clinical trials, animal safety studies, and mechanism of action investigations.
Excellent Safety Profile. FDA Generally Recognized As Safe (GRAS) status and approvals by international food authorities underscore its strong safety profile.
Other Ingredients: Vegetable wax (rice bran and/or carnauba), stearic acid(vegetable), magnesium stearate (vegetable), and silica.
Suntheanine SR is manufactured in the United States (Oregon) in a state-of-the-art, FDA-registered facility that meets or exceeds current Good Manufacturing Practices (cGMP). Quality control tests are performed at every stage of the manufacturing process from rigorous raw material testing to finished product testing.
Precautions
Consult your healthcare professional prior to use if you have or suspect a medical condition, are taking any medications, or are pregnant or nursing.
References
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Wang L, et al. Food Science and Human Wellness. 2022;11(3):467–475.
Kimura K, et al. Biological Psychology. 2007;74(1):39–45.
Yoto A, et al. Journal of Physiological Anthropology. 2012;31(1):28.
Hidese S, et al. Nutrients. 2019;11(10):2362.
Moulin M, et al. Neurology and Therapy. 2024;13(4):1135–1153.
Evans M, et al. Neurology and Therapy. 2021;10(2):1061–1078.
Dassanayake TL, et al. Nutritional Neuroscience. 2023;26(11):1138–1146.
Higashiyama A, et al. Journal of Functional Foods. 2011;3(3):171–178.
Baba Y, et al. Journal of Medicinal Food. 2021;24(4):333–341.
Bulman A, et al. Sleep Medicine Reviews. 2025;81:102076.
