L-theanine: Natural Supplement for Anxiety, Concentration and Other Health Issues

L-theanine has been studied extensively over the past few years for its health benefits and has been found both safe and effective for many health issues. Found in green tea, l-theanine is a little known amino acid that is just beginning to show how powerful it is to researchers who study its effects on many health issues.

What is l-theanine?

L-theanine is an amino acid found in green tea leaves. Green tea is made from unfermented leaves of the plant Camellia sinensiswhich all real, non-herbal tea comes from. In several studies of the health benefits of green tea it was found that l-theanine was one of the main active ingredients along with polyphenols and other antioxidants. L-theanine is unique in that it can cross the blood-brain barrier - a barrier that protects the brain from dangerous toxins - and is absorbed 100 percent into brain tissue. L-theanine has been studied extensively in Japan and has been approved for use there since 1964. Recently, many studies of l-theanine have occurred in the U.S. and in 2007 it was approved as safe to use by the Federal Drug Administration (FDA) in the U.S.

L-theanine for Stress and Anxiety

For thousands of years many cultures have used tea as a comforting and relaxing drink. Researchers now believe it is the amino acid l-theanine in tea that helps people relax without feeling drowsy. A study published in the June, 1999 issue of Trends in Food Science and Technology found that l-theanine reduced stress in women ages 18 to 22. Another study in 2007 found that when the participants consumed l-theanine before encountering a stressful situation their heart rate was lower during the stressful event than those who did not take l-theanine. Other studies have found that l-theanine can increase the hormone dopamine - the feel good hormone - in the brain as well as increase serotonin and gamma-aminobutyric acid (GABA), both necessary for relaxation. It has also been proven in many studies that l-theanine helps to promote alpha brain waves; the brain waves that help you feel relaxed while still being alert. The generally accepted dose of l-theanine supplements for stress and anxiety is 100 milligrams; however three cups of green tea may be just as effective.

L-theanine for Concentration

L-theanine is unique in that when it is mixed with caffeine, such as in tea, it has the power to improve alertness and concentration without the jittery effects of straight caffeine. A 2007 study found that the combination of 100 milligrams of l-theanine and 60 milligrams of caffeine - approximately 4 cups of green tea - helped study participants focus on complicated tasks. Since this combination helps to boost the activity of brain neurons it is believed to be beneficial for concentration, focusing on difficult tasks and learning.

L-theanine for Heart Health

A 2009 study found that drinking 3 cups of green tea daily can lower the risk of stroke by 21 percent. It is believed that both the antioxidants and l-theanine in tea are responsible for the prevention of stroke. A 1995 study in Japan found that l-theanine reduced high blood pressure back to normal, although it did not reduce normal blood pressure to lower rates. Another study found that l-theanine lowered LDL (bad) cholesterol; however it did not affect cholesterol levels as significantly as earlier green tea studies showed.

Other Health Benefits of L-theanine

Studies have found that l-theanine may help improve the efficiency of the chemotherapy cancer drugs doxorubicin and idarubicin as well as relieve some of the side-effects of these medications. Other health benefits of l-theanine include:

• Assists in weight loss
• Boost the immune system
• Aids in sleep
• Alleviates some symptoms of premenstrual syndrome (PMS)

Forms of L-theanine Available

L-theanine is available in capsule, tablet and powder form. There are also liquid mixtures available that combine l-theanine with other relaxing herbs such as chamomile that you mix with water to make a tea. Some energy and vitamin bottled waters also include l-theanine for energy and concentration. Of course the most natural way to take l-theanine is by drinking hot or cold green tea.

L-theanine has little to no known side-effects although the FDA recommends not exceeding 1,200 milligrams per day. The average dose is 100 to 200 milligrams per day. L-theanine supplements should not be given to children under age 18 or women who are pregnant unless advised by a doctor.

Sources:

Web-Us.com "L-Theanine: "How a Unique Anxiety Reducer and Mood Enhancer Increases Alpha Waves and Alertness" by Carolyn Perrini, CLS, CNC. Retrieved May 25, 2010.

VRP.com "L-Theanine Reduces Stress Response in Human Study" 2009. Retrieved May 25, 2010.

ScienceDaily.com "Green, Black Tea Can Reduce Stroke Risk, Research Suggests" Retrieved May 23, 2010.

Memorial Sloan-Kettering Cancer Center "L-Theanine" Retrieved May 23, 2010.