Are you a tea drinker? After water, tea is the most widely consumed beverage in the world and for good reason. You might not realize it, but tea can benefit your health.

What Is L-Theanine?

Green and black teas contain a water-soluble amino acid called L-theanine. L-theanine is a relaxing agent that is known to relieve stress and anxiety. These effects can also be felt in people with psychological disorders, including bipolar disorder. Some people even claim to experience improved concentration.

L-theanine makes up 1 to 2 percent of the dry weight of tea. Tea contains about 50 milligrams of L-theanine. Green tea has become a popular dietary supplement. It’s also a great source of caffeine.

Researchers believe that L-theanine may control aspects of human brain function. Electroencephalogram (EEG) studies have demonstrated that it can have a direct effect on the brain. The EEG scans show increased activity in the alpha frequency band. Alpha waves occur when your body is awake and alert but also relaxed. L-theanine has been shown to relax your brain without making you drowsy.

Benefits of L-Theanine

The jitters are commonly associated with caffeine sources, such as energy drinks. The L-theanine in tea keeps the jitters away by increasing the levels of the calming neurotransmitters serotonin and gamma aminobutyric acid (GABA). GABA neurotransmitters are all over the brain and stimulate nerve cells involved in anxiety inhibition as well as those that help to induce sleep.

Tea is also rich in antioxidants, which makes it an even more attractive drink. Antioxidants can be natural or man-made substances, and they help to stop or in some cases delay cell damage. Based on animal studies, the antioxidant effects of tea may also help with your cardiovascular health.

L-Theanine and Bipolar Disorder

Approximately 20 percent of adults in the United States report taking herbal products to treat medical illnesses, according to The Scientific World Journal. That equals about 1 in 5 adults.

Bipolar disorder is a mood disorder that causes severe mood changes. These changes may cause you to hurt yourself or others. If you suffer from bipolar disorder or another mood disorder, L-theanine may help. L-theanine may also help you if you suffer from anxiety or have problems sleeping.

If you think you suffer from bipolar disorder, you should see a professional. L-theanine has not been proven to be able to cure you of any disorder, nor has it been deemed a positive treatment option for everyone. Always talk to your doctor before stopping or beginning any new supplements.

Green tea contains L-theanine, but the studies and research done used much higher doses of the amino acid than what is in tea. You can find higher doses in supplements that are readily available for purchase. Supplements may help to improve your mood as well as your concentration and learning ability. Most supplements contain 200 to 400 mg of L-theanine per pill, but the amounts can vary.

L-Theanine Research and Studies

There are studies that have looked at the effects of L-theanine on mental state. One such study was done to see how L-theanine affects people with schizophrenia. Schizophrenia is a chronic and disabling brain disorder that affects about 1 percent of Americans. People with schizophrenia may have hallucinations, delusions, and an inability to think clearly or properly manage their emotions.

Schizophrenia isn’t completely understood, but it has been linked to problems with brain chemicals including the neurotransmitters dopamine and glutamate. Neurotransmitters help brain cells to communicate.

In the study, L-theanine was found to affect glutamate neurotransmission and seemed to improve symptoms in people with schizophrenia. Seventeen people with the mental disorder were given L-theanine supplements along with their antipsychotic medication for eight weeks. The results showed that L-theanine did improve symptoms as well as sleep quality. The findings seemed to suggest that L-theanine works by stabilizing the concentration of glutamate in the brain.

Another study aimed to see the effects of L-theanine on psychiatric disease-related behaviors in rats. It specifically looked at the effects of L-theanine on post-traumatic stress disorder (PTSD). PTSD is caused by the occurrence of a traumatic event that is not a normal part of human experience. Many soldiers suffer from this disorder due to the stress and things they see and experience while serving in the armed forces.

The study illustrated the possibility that L-theanine may affect the levels of some neurotransmitters in rats by changing gene expression. L-theanine seemed to produce significant gene changes that may be important in several disorders including:

  • PTSD
  • anxiety
  • mood disorders, including bipolar disorder

No such studies have been conducted on humans, and more research is needed. Initial studies, though, have proven to be positive.

Understand the Side Effects

As with any supplement, it’s important to watch out for any potential side effects. Not many side effects have been recorded for L-theanine, but consuming a large amount of green tea may cause you to suffer from nausea or irritability. The caffeine content may also upset your stomach. If your body doesn’t react well to caffeine, you should consult your doctor first.

Should I Take L-Theanine?

The studies with L-theanine and its treatment of mental disorders seem to be very promising. It’s important to note that all of the studies are in the beginning stage. Green tea has been around for years and has not posed much of a threat. The Food and Drug Administration (FDA) has given L-theanine a GRAS status, which means it’s generally recognized as safe.

For the most part, L-theanine may help to give you an extra push during the day. If you decide to take the higher doses that are found in L-theanine supplements, talk to your doctor first. If you’re currently on any medicines or have any health problems, it may not be safe.