L-Theanine

See also : Green Tea
Other Names : 5-N-ethylglutamine, gamma-glutamylethylamide, L-Theanine, L-Théanine, N-Éthyl-L-Glutamine, Teanina, Théanine.
Theanine (sometimes referred to as "L-theanine") is an amino acid found naturally in green tea. Theanine is isolated from tea leaves and the bay bolet edible mushroom, which is native to North America and Europe. Theanine, discovered in 1949 as a green tea component was approved in 1964 in Japan for use in foods and beverages. In the United States, theanine supplements received a generally recognized as safe rating from the Food and Drug Administration.

Special Precautions of L-Theanine

• Theanine side effects include stomach upset, headache and dizziness. Safety information during pregnancy or nursing is lacking.
• There's also some concern that taking theanine in combination with sedatives, lipid-lowering medications, and/or drugs used in chemotherapy may produce harmful effects.
• Medications for high blood pressure (Antihypertensive drugs) interacts with THEANINE
• Stimulant drugs interacts with THEANINE

The benefits of L-Theanine are

Experts believe L-theanine is effective because it can cross the blood-brain barrier. This allows it to affect the central nervous system. It works by blocking neurons from sending stress signals. It has also been shown to improve cognition and it works in synergy with caffeine.

• Stress: According to a study published in the January, 2007 issue of the journal "Biological Psychology," theanine exerts anti-stress effects. It reduces heart rate and physiological and psychological stress responses.
• Relaxation : Alpha brain waves cycle between 8 to 12 Hz. This is considered a relaxed brain-wave state. This is the dominant brain-wave state when your eyes are closed. Alpha brain waves help balance mood and enhance creativity. A study published in 2008 in "Asia Pacific Journal of Clinical Nutrition" found that 50 mg of theanine significantly increases alpha brain wave activity within 40 to 90 minutes of ingestion.
• Immunity : Taking green-tea-derived theanine and antioxidants in supplement form may help prevent the flu, suggests a study published in BMC Complementary and Alternative Medicine in 2011. Every day for five months, the study's 197 participants took either a placebo or a capsule containing theanine and catechins (a class of antioxidants found in green tea). Results revealed that incidence of flu was significantly lower in the theanine/catechin group (compared to the placebo group).
• Brain Health : A 2010 study from Nutritional Neuroscience suggests that a combination of theanine and caffeine may help improve cognitive performance. For the study, 44 young adults took either a placebo or a combination of theanine and caffeine prior to performing a demanding cognitive task. Researchers found that the combination of theanine and caffeine significantly improved accuracy and alertness and helped to increase focus while performing the task. Additionally, findings from an animal-based study published in Free Radical Biology & Medicine in 2009 suggest that theanine may inhibit buildup of amyloid beta (a substance that forms the brain plaques associated with Alzheimer's disease).
• Depression : Theanine may help relieve depression, according to an animal-based study published in Phytotherapy Research in 2011. In tests on mice, scientists discovered that theanine produced an "antidepressant-like effect."
• Weight Loss : Theanine shows promise as a weight loss aid, according to animal-based research published in the journal In Vivo in 2004. In an experiment involving mice fed green tea powder, researchers found that theanine and caffeine found in the powder appeared to prevent weight gain and fight the buildup of fat.