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What other names is Theanine known by?

2-Amino-4- (ethylcarbamoyl) Butyric Acid, 5-N-ethylglutamine, Gamma-glutamylethylamide, L-Theanine, L-Théanine, N-Éthyl-L-Glutamine, Teanina, Théanine.

What is Theanine?

Theanine is an amino acid (a building block for proteins) found in green tea.

People use theanine for treating anxiety and high blood pressure, for preventing Alzheimer's disease, and for making cancer drugs more effective.

Insufficient Evidence to Rate Effectiveness for...

  • Anxiety. Early research suggests that taking theanine might make unstressed people feel more tranquil. However, theanine does not seem to have this effect when used by people who are anxious.
  • Preventing dementia including Alzheimer's disease.
  • Treating high blood pressure.
  • Increasing the treatment effects of cancer drugs.
  • Other conditions.
More evidence is needed to rate the effectiveness of theanine for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

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