Is L-Theanine Effective for ADHD?

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ADHD, attention deficit hyperactivity disorder, is characterized as abnormal levels of inattentiveness, impulsivity and overactivity. ADHD affects 3 percent to 5 percent of children, and while scientists aren’t certain of the exact cause, it is possible ADHD is hereditary, and that lower dopamine levels may play a role in its severity. While ADHD is commonly treated through prescription medications, natural supplementation such as L-theanine may be used to help diminish symptoms of this condition. Talk to your doctor before using L-theanine for ADHD.


L-theanine is classified as an amino acid, and this water soluble chemical is in some mushrooms and green tea. Proponents of this amino acid claim it may enhance your body’s antioxidant count and promote mental relaxation. Preliminary studies have shown theanine may have anti-obesity and anti-tumor properties as well as preventing certain forms of cognitive dysfunction. Animal studies suggest L-theanine affects the levels of serotonin and dopamine, which may also contribute to its calming effects; however, human studies regarding this use are minimal.

Effectiveness on ADHD

Preliminary studies suggest theanine may indirectly reduce ADHD hyperactivity by promoting a sense of relaxation and enhancing the release of dopamine. The “Trends in Food Science & Technology” journal outlines a human study saying theanine created an increase in a-waves, which are brain waves associated with relaxation. This increase in a-waves indicates theanine may help relieve hyperactivity without causing drowsiness. Evidence suggests an ADHD brain does not properly respond to dopamine, and the brain may not be producing normal levels of this neurotransmitter. A study performed by the University of Shizuoka School of Food and Nutritional Sciences found theanine induces the release of dopamine in rats. If this amino acid is able to increase the production of dopamine in humans, it may assist in the reduction of ADHD symptoms. Further studies are required to prove this bodily response to theanine.

L-Theanine Sources

The primary source of L-theanine is green tea. Scientists have also derived theanine from the Boletus badius mushroom, which grows throughout the United States. If you are sensitive to caffeine or are allergic to mushrooms, you may consume theanine through oral supplements. While data supporting the clinical function and proper dosage of theanine is sparse, supplementation studies typically used 200 to 250 mg once daily.

Safety Considerations

L-theanine is generally considered safe; however, discuss use of this supplement with your physician before consuming. Side effects may include dizziness, headache and gastrointestinal discomfort; however, these adverse reactions may be caused by other ingredients in green tea or mushrooms. If you are taking chemotherapeutic drugs, lipid lowering medications or sedatives, do not use theanine without your doctor’s consent.