08 July, 2011
L-Theanine for Obsessive-Compulsive Disorder (OCD)
Obsessive-compulsive disorder is an anxiety disorder that affects over 2.3% of the American population. Sufferers generally experience recurrent, unwanted ideas or compulsive, irrational behaviors. While the repression of compulsive behaviors produces anxiety, carrying out those acts can bring relief. According to the National Institute of Mental Health, obsessive-compulsive disorder often occurs alongside depression, personality disorders, eating disorders, or other anxiety disorders. The Memorial Sloan-Kettering Cancer Center suggests that the amino acid L-theanine may be useful in the treatment of anxiety disorders, although current research on its efficacy is not conclusive.
Discovered by Japanese scientists in 1950, the amino acid L-theanine is considered "generally recognized as safe" for human consumption by the U.S. Food and Drug Administration. Large amounts of this amino acid is found in green tea, although still in concentrations far lower than those used therapeutically. In addition to being employed as a treatment for anxiety, L-theanine is also used to support immune function, reduce the risk of stroke, and enhance the activity of some chemotherapy drugs.
L-theanine can penetrate the blood-brain barrier, exerting psychoactive effects on the central nervous system. L-theanine increases serum dopamine and GABA levels; it also demonstrates a low binding affinity to post synaptic glutamate, AMPA, NMDA, and kainate receptors. While known to affect serotonin levels in the brain, L-theanine's exact effects are as yet uncertain. L-theanine's effects on mood and anxiety are believed to be the result of its cumulative actions on these neurochemical pathways.
These effects may produce relaxation and relief from anxiety by increasing the production of alpha waves in the brain. In one study, researchers found that the production of alpha waves increased dose-dependently 40 minutes after the ingestion of 50 to 200 milligrams of L-theanine. These waves are known for producing the relaxed, high-functioning mental states often associated with peak performance. Nonetheless, there have been no studies on the efficacy of L-theanine in the treatment of obsessive-compulsive disorders. All current evidence can only be considered speculative or anecdotal.
Side-Effects and Contraindications
Current research suggests that L-theanine is remarkably safe. As a major component of tea, the most commonly consumed beverage in the world after water, it is generally believed to have an excellent safety record. There are no known drug interactions or contraindications for the use of L-theanine. However, therapeutic doses are generally somewhat higher than those generally consumed through tea, resulting in a low incidence of side effects including headache, dizziness, or gastrointestinal discomfort.
- Hill Street Studios/Blend Images/Getty Images