Written by Slawomir (“Swavak”) Gromadzki, MPH

Anxiety is regarded as one of the most common complaints today. It is an unpleasant emotion we have all experienced and we are more likely to suffer from it when we are under stress. It is interesting that one of the top search terms that people are looking for today using internet browsers is: “L-Theanine for anxiety”. L-Theanine is a unique amino acid compound found almost exclusively in the tea plant (Camellia sinensis). It has become famous for its ability to reduce stress levels and promote calm, relaxed state of mind. In the brain L-Theanine raises alpha-brain wave activity, associated with increased sense of relaxation. It also has many other benefits including antioxidant effect, cardiovascular and immune support. L-Theanine has become so valuable and popular relaxant today because at the same time it doesn’t cause drowsiness but even increases alertness and cognitive function of the brain including focus, memory and attention during the day. One of the best L-Theanine benefits is that it is virtually free from side effects, even at larger dosages and used over longer period of time.

Helps improve mood & promotes relaxed state of mind

One of the key L-Theanine benefits is its ability to increase calmness and relaxation without creating sedative effect. A Japanese study showed oral L-Theanine administration of a single dose of 200 mg led to increased alpha-brain waves and sense of relaxation. By now we know that brain converts L-Theanine into body’s key relaxing neurotransmitters GABA, dopamine and serotonin. Scientists have found that L-Theanine’s relaxing and anti-stress effect is most evident in people with high baseline anxiety.

Increases energy & alertness during the day while promoting restful sleep at night

The effect of L-Theanine is so unique and desirable because during the day it helps relieve tension while increasing alertness and energy levels and at night it aids relaxation of the mind for a more restful and deeper sleep. This effect of L-Theanine is associated with increased levels of “happy” neurotransmitter serotonin which is known for its simultaneous calming and energising effect. A 2011 study found that the L-Theanine supplement was a great aid to improve quality of sleep and reduce time to fall asleep. A 2015, found that L-Theanine was beneficial in increasing cerebral blood flow and oxygenation of the brain.

Boosts immunity, reduces oxidative damage, supports slimming, heart & liver health

Some studies have shown that L-Theanine may be helpful in preventing cognitive dysfunction and maintaining normal cholesterol levels in the heart and brain arteries. There is evidence L-Theanine has the ability to increase activity and effectiveness of immune system. It also restored the antioxidant capability of liver cells, helping prevent liver damage. A growing number of people also claim to have experienced some weight loss associated with regular use of L-Theanine supplements.

L-Theanine vs green tea

It is  much wiser and healthier choice to take L-Theanine alone than drinking green tea. Green tea is often recommended as a relaxing beverage but it doesn’t contain enough L-Theanine to impose a desirable effect, and it also may make you wake up to go to the bathroom. In addition, green tea leads to iron deficiency and can be high in caffeine, a psychoactive substance that may trigger or exacerbate anxiety. Therefore, those who expect calming and relaxing effect are encouraged to use supplements containing optimum dose of 200mg of L-Theanine per tablet.


In animal research, L-Theanine appears to be remarkably safe as very high doses have failed to cause toxicity.

however, as a precaution, pregnant and breast feeding women should consult a health practitioner before taking L-Theanine.

L-Theanine may lower blood pressure. Therefore, if you have low blood pressure or take blood pressure medication speak with your doctor before using L-Theanine.


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