Does L-theanine have health benefits?

Research suggests that L-theanine might provide a range of health benefits, which may include improved mental focus and better sleep quality.

This article provides an overview of L-theanine, including its potential benefits and risks and its dosage.L-theanine is an amino acid. The human body does not produce this compound, and it is not essential for humans. Green tea, black tea, and certain types of mushroom naturally contain L-theanine.L-theanine powder

L-theanine may affect the levels of certain chemicals in the brain. These include serotonin and dopamine, which influence mood, sleep, and emotion, and cortisol, which helps the body deal with stress.

A change in the balance of these chemicals can change a person's mood or stress levels.

Small studies and tests on animals have shown that L-theanine may offer a range of benefits. Experts consider it to be generally safe, but there is currently a lack of high-quality research in humans to confirm its benefits.
1. Better mental focus

Many people drink black or green tea while at work, believing that it boosts their mental focus. A 2012 study supports this idea.

The researchers found that people who took 100 milligrams (mg) of L-theanine made fewer errors in an attention task than those in the placebo group. Drinking 50 mg of caffeine or combining the L-theanine and caffeine also improved people's focus.

More research is necessary to determine how L-theanine might affect a person's attention and focus.
2. Improved sleep

woman in a deep sleep
L-theanine may help people sleep more easily.
Several studies have suggested that L-theanine could help people relax before bedtime, get to sleep more easily, and sleep more deeply.

These benefits may result from the specific effects that the amino acid has on brain chemicals that play a role in sleep.

A 2018 study found that people reported having greater sleep satisfaction after taking 450–900 mg of L-theanine daily for 8 weeks. The study participants had generalized anxiety disorder and were taking antidepressants.