The Advantages of L-Theanine Supplementation

Theanine is an amino acid found only in plants and is naturally concentrated in green tea and some mushroom varieties. It is a non-protein amino acid.

How L-Theanine Works in the Body

Theanine was discovered in 1949 and has been well studied and regularly used in Japan since that time.

With a chemical structure similar to the neurotransmitter glutamine, L-Theanine passes the brain-blood barrier within 30 minutes of ingestion. Glutamine is the forerunner of the two most important neurotransmitters in the body, glutamate and gamma-aminobutyric acid (GABA).

Glutamate is an excitatory neurotransmitter and excites the receiving neuron with an electrical signal. GABA is an inhibitory neurotransmitter that hinders the receiving neuron from firing its own electrical signal. Researchers hypothesize L-Theanine may increase levels of GABA which helps reduce the over excitement caused by glutamate.

It is also thought L-Theanine may increase levels of serotonin and dopamine. Both serotonin and dopamine are neuromodulators. Neuromodulators operate slower than neurotransmitters but can affect more neurons at the same time.

Serotonin helps regulate mood, sleep, appetite, and memory. Dopamine helps regulates motor control and impacts emotional feelings of motivation including reward and reinforcement.

In a study conducted on rats, researchers studied the effects of theanine on neurotransmitters in the brain. From this study, researchers believe theanine helps release dopamine and inhibit excitatory glutamate neurotransmission.

Researched Based Benefits of L-Theanine Supplementation

Possibly Reduces Anxiety and Stress to Improve Sleep Quality

In a randomized double-blinded placebo-controlled clinical trial, researchers concluded L-Theanine supplementation has the potential to help provide relief from stress-related ailments and cognitive impairments.   Participants were given either a placebo or 200 mg of synthetic L-Theanine to be taken orally before bed for four weeks. The trial found L-Theanine promotes reduced depression and anxiety while aiding sleep quality. The four-week trial also showed L-Theanine may aid executive functioning and verbal fluency scores.

In a study using 0.5 mg/kg of participant’s body weight, L-Theanine supplementation may influence the central nervous system. This influence helped increase alpha-band activity in the brain and promoted a relaxed, but alert mental state.

In another double-blind, placebo-controlled clinical trial of ninety-eight male children diagnosed with attention deficit hyperactivity disorder (ADHD), 200 mg of Theanine supplementation was taken twice daily. This trial showed L-Theanine may significantly help improve sleep quantity and quality in children with ADHD. In a sleep questionnaire, parents noted longer, deeper sleep with less movement with the Theanine supplement. This dosage seemed well tolerated with no significant adverse events noted.

Aids Cardiovascular Functionality

The American Heart Association links chronic stress to behaviors that may increase the risk of heart disease including high blood pressure. Many people use unhealthy means or fall into bad habits to manage stress. Overeating, smoking, drinking alcohol, and even reduced physical activity can all be coping mechanisms to deal with chronic stress. These unhealthy habits may increase blood pressure and strain artery walls.

For individuals dealing with high anxiety, L-Theanine may be helpful. One study involving high-stress-response adults found a 200 mg supplementation of L-Theanine may significantly help suppress rising blood pressure when performing mental tasks in acutely stressful situations. L-Theanine supplementation showed blood pressure benefits in stressful mental situations over placebo and caffeine supplementation.

Helps Increase focus

Theanine helps strengthen brain function and supports mental focus, especially when taken in combination with caffeine. A double-blind, placebo-controlled clinical trial conducted by researchers including E. A. De Bruin suggests L-theanine (97 mg) and caffeine (40 mg) supplementation taken together may significantly support the ability to focus attention during a challenging cognitive task. This trial also found improvements in self-reported alertness and accuracy when switching tasks while reducing self-reported tiredness.

In a double-blind cross-over study involving college-aged students, eighteen volunteers were sorted by their propensity for anxiety. Students were given a placebo or 200 mg of Theanine. Performance assessments were taken 15-60 minutes after supplementation.

No significant effects of L-Theanine supplementation over placebo were noted for those students with a minimal propensity for anxiety. However, for the high anxiety students, L-Theanine may provide significant physical and mental improvements. These included reduced heart rate, enhanced alpha-band activity, increased visual attention, and improved reaction time.

Aids Immune System

A randomized controlled trial of Japanese healthcare workers found a combined supplementation of green tea catechin (378 mg/day) and theanine (210 mg/day) may significantly aid the reduction of the rate of influenza infection. In the five-month study, thirteen percent in the placebo group became infected and tested positive for influenza while only four percent of the supplement group did.

In an observational study, the daily consumption of 1-5 cups of green tea by Japanese schoolchildren appeared to help reduce the rate of influenza infection during the type A influenza endemic in Japan during the winter of 2008-2009.

Research in Cancer

Researchers Sugiyama, T. and Sadzuka, Y. have conducted several studies on mice to discover the possible uses of Theanine to aid cancer treatment.

In one study, they found L-Theanine may aid the inhibition of glutamate transporter to help keep chemotherapy drugs out of normal tissue.

However, seeking to obtain L-Theanine supplementation solely from drinking green tea may have adverse effects on the efficacy of the chemotherapy drug, bortezomib (BZM). In a study involving both in-vitro and vivo, researchers found the effects of the polyphenols in green tea prevented tumor cell death by BZM.

Possible L-Theanine Side Effect

L-Theanine is considered safe when taken between 100-200 mg. No confirmed side effects have been noted with L-Theanine supplementation.

The United States Food and Drug Administration (FDA) does not regulate L-Theanine supplementation. However, L-Theanine is generally recognized as safe (GRAS) by the FDA. In a letter dated September 10, 2014, the FDA communicates they have no questions concerning GRAS L-Theanine use in various foods at levels up to 250 mg/serving.

Discover the Benefits of L-Theanine Supplements

Green tea provides roughly 10 mg of L-Theanine per cup. Most of the clinical trials referenced in this article used between 50-400 mg of L-Theanine. To obtain these levels of L-Theanine from green tea alone, you would have to drink 5-40 cups of green tea.

Taking theanine supplements is the most efficient way to realize the possible clinical benefits. SOS’s 150 mg L-Theanine capsules are a cost-effective way to discover the benefits of adding L-Theanine to your regime. For less than seven cents a capsule, you can aid stress reduction, promote more restful sleep, and help boost your immune system against viral respiratory infections.

When taken with caffeine, L-Theanine may help increase your mental focus and accuracy. SOS conveniently carries caffeine supplements, too. Caffeine supplements are a great way to get the possible energizing benefits of caffeine without the added calories and cost of energy drinks.

You can conveniently purchase SOSs products on their website or on Amazon.com.

These statements on L-Theanine supplementation have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. Seek appropriate medical advice before starting any supplement regime.

The content of SOS’s website is for information only, not advice or guarantee of outcome. Information is gathered and shared from reputable sources; however, SOS is not responsible for errors or omissions in reporting or explanation. No individuals, including those taking SOS products, should use the information, resources or tools contained within to self-diagnosis or self-treat any health-related condition. SOS gives no assurance or warranty regarding the accuracy, timeliness or applicability of the content.

Sources

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