What Are the Benefits of L-Theanine?
Mmm, tea! There’s nothing quite like a steaming cup of this ancient elixir for both its calming properties and its caffeine that keeps us alert. These two seemingly opposing qualities have spurred debate: Is it possible the soothing effects of tea are an intrinsic property of the beverage, or is this due instead to the relaxing ritual of making and drinking a cup?
What the research shows
L-theanine, an amino acid present in tea leaves, contributes to tea’s rich umami taste as well as its peace-inducing quality. Studies have found that the combination of caffeine and L-theanine can reduce mental fatigue, ease stress, and improve cognitive function — while also mitigating some of caffeine’s negative effects.
L-theanine is believed to ease the effects of stress by inhibiting cortical neuron excitation. Additional research shows that ingesting L-theanine leads to increased alpha brain waves, the same waves produced while relaxing or meditating. It can also increase levels of the neurotransmitter GABA, which plays a role in preventing anxiety and depression.
A study published in the Journal of Physiological Anthropology reported that L-theanine decreased participants’ tension and anxiety levels. Another study showed that L-theanine reduces the effects of caffeine on blood pressure, suggesting that it could effectively temper acute stress.
A further study discovered that L-theanine lowered the heart rate of individuals with a high propensity for anxiety. The same study also found that a single dose improved reaction time and attention performance in the same group. One of the unique aspects of L-theanine is its ability to help regulate stress while also improving concentration.
How to get it?
Green teas — and especially matcha — contain the most L-theanine, while black teas have less due to their processing. L-theanine is also available in supplement form.
If you are interested in the calming and focusing effects that L-theanine can provide, but still want to enjoy your morning coffee, try an L-theanine supplement with your daily cup.
This post was originally written by Experience Life contributing writer, Marco Dregni, for Experience Life.