Black tea and green tea including matcha contains different levels of l-theanine
Inna Finkova / Alamy Stock Photo
L-theanine is an amino acid that is naturally found in tea leaves. First attached to TEA’s soothing effects in the 1940s, it is now sold as a supplement to stress relief, focus and better sleep. Research in its effects has so far Ben Limited, but there are exciting hints that it can have severe yefits for the brain, especially in people who have anxiety.
What advantageous effects can l-theanine have?
Research in L-Theanine is promising, but still in her infant. “Research is limited, the studies are small and the results are mixed,” Saystal Haskell-Ramsay at Northumbria University in the UK.
However, data from small trials suggests that L-Theanine can lower a person’s blood pressure while performing a task that requires attention, and in times of stress it can help lower a person’s heartbeat and tempable spigure of the stress hormone cortisol. There is also some evidence that it can increase relaxation and focus.
What effects the l-theanine has on the brain?
When absorbed into the bloodstream via the gut, L-Theanine is able to cross the blood-brain barrier. It has a similar structure like the brain chemicals glutamate and gaba, which are neurotransmitters involved in turning signaling up and down the brain. Rodent studies also suggest that L-Theanine can increase the levels of dopamine and serotonin, which are involved in many aspects of brain function, including mood and reward.
L-theanine also seems to increase the alpha-brain wave activity, which is linked to a state of calm, alerted wakefulness. “If you close your eyes, Alpha suddenly goes up,” says Manuel Gomez-Ramirez at the University of Rochester in New York.
Is this advantageous for mood and well -being?
In general, an increase in alpha-brain waves can help the brain set distractions and focus, and L-theanine can improve this effect. “The higher the alpha, the more you vote beyond the world,” explains Gomez-Ramirez. This effect is stronger when combined with caffeine as the two compounds “have some out of synergistic effect,” he says.
The effect of L-theanine on alpha waves seems more pronounced in people who are already anxious, and a study in study rats found L-theanine’s effect on dopamine and serotonin levels in certain brain areas were associated with fewer depression-like symptoms. However, evidence in humans is inconsistent as some studies find no benefit to generalized anxiety disorder and others reporting lowered stress and anxiety levels.
If it facilitates anxiety, this may explain L-theanines alleged benefits for sleep. An analysis found that it helps people fall asleep quickly and improves sleep quality.
Is there enough l-theanine in tea to have an effect?
Tea-inclusive black tea and green tea, such as Matcha content L-Theanine at different levels, about 5 to 40 mg per day. Cup. It is possible that this can offer mild effects, but most L-Theanine studies use doses around 200 mg, similar to the level typically found in supplements.
How good is the proof of L-Theanine?
Most studies use small sample sizes and spur only short -term effects that often test a single dose or a few weeks supplement. “It’s definitely promising, but we just need more work in this area,” says Amanda Bulman at the University of Canberra in Australia.
A complication is studies that often combine L-theanine with other ingredients that cloud the evidence. “It’s hard to tell what is the news that does the work,” says Haskell-Ramsay. “It is impossible to choose that this has an effect.”
Haskell-Ramsay also warns, “People often take it daily, in the long term, and we just control the data about it”.
Topics: