Anxiety was on the rise even before COVID-19 pushed us all into even more pronounced panic. So anything that can help us humans feel calmer and more centered is particularly welcome right now.
Several fascinating studies have shown that theanine, a compound found in tea and some mushrooms, is connected to better brain and heart health and to longevity.
Terri Hirning, a motivational speaker and health advocate, said that for more than a decade, she has used theanine as a treatment for her son to help him recover from autism.
“Some also find theanine helpful for night wakeups where your mind just won’t shut off,” Hirning said.
What Is Theanine?Theanine is an amino acid found in tea plants and certain mushrooms. It's similar in structure to glutamic acid and glutamine, compounds essential to many bodily functions, including protein synthesis and neurotransmission.
Theanine’s BenefitsTheanine has been shown to be neuroprotective by reducing excitatory glutamate, delaying neuron death following stroke, and promoting neurogenesis (the creation of new brain cells).
Positive Synergy With CaffeineIn nature, theanine nearly always comes packaged with caffeine. Theanine is found in the highest concentrations in green tea, especially shade-grown green tea, which has higher levels of both theanine and caffeine. In laboratory experiments, it appears that theanine is most beneficial when paired with caffeine.
For example, in an interesting experiment published in March 2015, a team of neuroscientists at Northumbria University in the UK gave 24 people—12 habitual caffeine consumers and 12 non-consumers—in random order, over four visits, just caffeine, just theanine, both theanine and caffeine together, and a placebo.
Afterward, participants were tested on a range of mental tasks.
Those who were given caffeine alone reported fewer headaches and mental fatigue than when they were tested before the dose and likewise demonstrated improved reaction time and a better ability to process visual information quickly.
Participants given just theanine reported having more headaches during the testing. Where the people given caffeine had improved scores on the mental math component of the test (counting backward in increments of seven), those given theanine alone didn't.
However, the study participants who took the caffeine and theanine together enjoyed all the benefits of caffeine and none of the downsides of theanine alone and did even better than the caffeine-only group on mental math, as well as on language skills.
Help With CognitionScientists believe that some of the brain effects associated with theanine stem from its resemblance to glutamine, a powerful excitatory neurotransmitter. Recent research has shown that theanine can occupy glutamate receptors and that it's able to pass through the blood-brain barrier to exert its relaxation effect.
The study was a randomized double-blind, placebo-controlled trial, which means that neither the researchers nor the subjects knew whether they were taking theanine or a placebo. This is considered the gold standard for obtaining high-quality evidence, although the study didn't limit the subjects’ normal intake of tea, which means that the overall intake of both theanine and caffeine wasn't strictly controlled.
Counteracting Negative Effects on the BrainAlthough the use of cannabis is controversial, 37 states have legalized medical marijuana and 18 states have legalized its recreational use. Chronic cannabis use in adolescence is associated with negative effects on brain development, which may be a trigger for schizophrenia and may cause anxiety, paranoia, and other cognitive impairments.
Theanine had a positive effect on the young rats’ brains, the researchers found.
Good for Your HeartThere's also some evidence that theanine has beneficial cardiovascular effects. In one 2012 study, Japanese researchers found that high-stress-response participants (those whose blood pressure tended to rise when facing stress) given 200 milligrams of L-theanine and then asked to perform high-stress tasks not only experienced less anxiety, but also had lower blood-pressure readings than high-stress-response participants who were given a placebo. Theanine, the researchers wrote, “attenuates the blood-pressure increase in high-stress-response adults.”
Best Ways to Get TheanineTheanine was originally identified by a Japanese scientist interested in why gyokuro (shade-grown, rolled-leaf) tea was so rich in umami (deep flavor), almost like a savory soup. Sure enough, gyokuro was found to contain abundant amounts of theanine.
Gyokuro isn't always easy to find in the West, unlike matcha, the tea-ceremony form of green tea in which the leaves are ground to a fine powder so that it brews quickly and thoroughly—and you drink the powdered leaves themselves, giving you a concentrated dose of everything in the tea.
Matcha is very trendy now and can be ordered in coffee shops, tea houses, and even smoothie bars. How it’s brewed or even whether it's brewed at all doesn’t much matter, because when you drink matcha, you're consuming everything in the tea.
All true teas (made from the leaves of the tea plant, Camellia sinensis), whether black, white, green, oolong, or pu-erh, contain theanine. If you’re not a tea drinker, you can get theanine by adding matcha powder to foods and desserts: Sprinkle it on fruit salad or ice cream, use it to make a healthy cake frosting, or make some matcha-infused energy balls.