Mechanism of Suntheanine®
• Suntheanine® is absorbed in the small intestine via a sodium-coupled active transport process and crosses the blood-brain barrier where it is absorbed into the brain in a dose-dependent manner.
• Suntheanine® may compete for absorption in the intestinal tract and brain with amino acids found in the methionine group, including isoleucine, leucine and valine. Concentrations of other amino acids are unchanged by Suntheanine®.
• Suntheanine® directly stimulates production of alpha brain waves (a state often achieved by meditation, one of deep relaxation and mental alertness).
• Suntheanine® plays a role in the formation of the inhibitory neurotransmitter GABA and increases dopamine release through modulation of glycine and AMPA receptors. Suntheanine® promotes a relaxation and excitatory inhibition effect without leading to drowsiness.
Regulatory Status of Suntheanine®
• L-Theanine was approved in Japan in 1964 for unlimited use in foods. In 2000, Suntheanine® was introduced in the U.S. for use in dietary supplements. Suntheanine®, as produced via a patented enzymatic fermentation method, resulting in an enantiomerically pure L-Theanine, was GRAS affirmed in the U.S. in 2005 for use in foods and beverages up to 250 mg/serving, with no limitation on the number of servings. In 2007 the U.S. FDA confirmed the GRAS Affirmation in its Letter of No Objection (GRN 000209).
Suntheanine® Safety Studies
Suntheanine® has been shown to be safe for use as directed based on the following positive toxicology studies: 28 Day Subacute Toxicity Study, 78 Week Evaluation of Toxicity and Carcinogenicity, Acute Toxicity/LD-50 Determination and Ames Salmonella/Microsome Plate Test for Mutagenicity.
How Should Suntheanine® be Taken?
There is not a set schedule for taking Suntheanine®, and should be taken when levels of stress are noticed. The effects of Suntheanine® are generally felt within 30 minutes, and have been shown to last up to 8 – 12 hours. Consumption of Suntheanine® is not affected (positively or negatively) by the consumption of food. Suntheanine® may be taken at any time.
Recommended Use of Suntheanine®
The intended use for Suntheanine® is that of a relaxant to produce mental and physical relaxation without inducing drowsiness. Based on the results of clinical studies, it has been established that Suntheanine® is effective in the range of 50 – 200 mg. It is suggested that subjects with higher levels of stress consume a minimum of 100 mg for best effects. Please note that if a person is already calm and relaxed, little to no effect will be noticed at any level of consumption.