Theanine Side Effects
Can Too Much To Harmful?

Few people have heard about theanine, but this supplement probably ranked amongst one of the safest in existence.

Although theanine is an important tea constituent, theanine tablets are made synthetically using enzymes in laboratory rather than extracted from tea leaves.

This means that you don't have to worried about environmental pollution and herbicide contamination of tea leaves.

However, given that it is manufactured synthetically, is it a cause of concern? Can consuming too much cause theanine side effects?

To answer this question, we need to look into its safety records of long term human usage.

Synthetic theanine has been licensed for unlimited use in all foods (except infant food) in Japan since 1964. These include chocolate, soft drinks and herbal teas.

This is impressive. In Japan, food ingredients need to undergo extensive testing before they are approved for unlimited use.

Studies have found theanine to be harmless, even at very large quantity. Tests include the Acute Toxicity/LD50 Determination, which uses super high concentration of 5 grams per kilogram.

(That is, the equivalence of a 60 kilogram adults consuming 300 grams of theanine a day!)

In 2007, theanine receives the GRAS affirmation (Generally Recognised as Safe) from the United States FDA for its use in a number of food and beverage products.

Amazingly, for the past 40 years, there have been no scientific reports of theanine side effects.

There have been no known interactions of theanine with other prescriptions or over the counter drugs.

You may be surprised to learn that past studies have found that theanine helps improve the efficacy of anti-cancer drugs by enhancing its effectiveness and reducing its side effects.

This may be due to theanine relaxing properties, which reduces anxiety in patients' mind and help them sleep sounder at night, therefore enhancing the body's self healing process.

I have been asking myself this question: Is this a magic drug or something? Can it really have no side effects?

I guess the answer lies in the real nature of theanine. You see, it is an amino acid, the building block of protein, the stuff you and me are made of.

Theanine is related to glutamine, the most abundant, natural occurring amino acid produced by the human body. Other sources of glutamine includes chicken, eggs, spinach and beans.

Theanine helps relax the mind, and when you feel relaxed, things seem to take care of itself.

Most credible sources recommend taking 50 to 200 milligrams a day with or without food, with up to 2 to 3 times daily as needed.

Studies have also reported good results at up to 400 milligrams a day.

At high concentration (say 1000 milligrams), theanine may make you feel over-relaxed. So beware, especially if you are involved in manual work.

Leek Raj Jujena, Chu D, Okubo T, Nagato Y, and Yokogoshi H (1999). L-theanine – a unique amino acid of green tea and its relaxation effect in humans. Trends in Food Science & Technology. 1999;10(6-7):199-204.

From The Experts. http://www.suntheanine.com/FromTheExperts.cfm. Suntheanine.

Yokogoshi H, et al. (2001). Institute for Traditional Medicine (www.itmonline.org). Theanine effects on premenstrual syndrome. Amino Acid Supplements IV: Theanine. Subhuti D. Referencing: Proceedings of the Nogei Kagaku Kai, Bioscience, Biotechnology, and Biochemistry. 2001;75:166.

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