You climb into bed, close your eyes…and your mind revs up. You start fretting…about money…health…people…undone tasks. You just can’t relax. Or you fall asleep, only to wake up—worried. Maybe you’re worried about not being able to fall asleep. It’s anxiety, and it’s a common cause of insomnia.

A relaxing routine before bedtime and a bedroom suited for sleeping are key parts of the solution, but sometimes you need extra help. One thing you want to avoid at all costs—dependence on sleeping pills, which can be addictive, lead to drowsiness and accidents the next day and, let’s cut to the chase, are downright dangerous over the long term.

For help easing into a relaxed, deeper sleep, consider instead a supplement derived from green tea—L-theanine. It’s becoming popular as a supplement, and it’s showing up as an ingredient in “relaxation beverages” such as Just Chill and NeuroSleep.

To learn more, we spoke with naturopathic physician and Daily Health News contributing editor Andrew Rubman, ND, medical director of the Southbury Clinic for Traditional Medicines.


An amino acid found in tea, and in especially high levels in green tea, L-theanine increases alpha wave activity—the kind of brain waves associated with the most relaxed sleep state. This, in turn, increases the production of serotonin, dopamine and GABA (gamma aminobutyric acid), a trio of neurotransmitters that promote relaxed, positive moods.

While L-theanine has been studied as an antianxiety treatment, there are only a few clinical studies of its use for insomnia. In one, in boys with ADHD, a supplement containing 200 mg of L-theanine twice a day (400 mg total daily) for six weeks improved both sleep time and quality. In a Japanese study, adult men who took 200 mg a day for six days didn’t sleep any longer—but they felt like they did. They also reported feeling more relaxed before bedtime, having fewer nightmares, and feeling less tired and more refreshed during the day.

It’s a safe supplement, says Dr. Rubman. One key element is that it relaxes without causing grogginess…and there is no evidence that it can become addictive, as many sleeping pills can.


If you want to try L-theanine to help you sleep, Dr. Rubman suggests that you drink a cup of green tea as a soothing nightcap before bed rather than just taking the supplement…it’s cheaper and may be as effective. A typical cup of green tea may have less than 50 mg of L-theanine, which is less than the 200 mg used in studies, but may help some people. Worried about the caffeine? Don’t be, says Dr. Rubman—L-theanine inhibits the ability of caffeine to attach to receptors in the brain, so you’ll be getting very little caffeine from one cup of the tea. (Green tea is already low in caffeine—about one-third as much as in regular tea—but you can also drink decaffeinated green tea, which has the same amount of theanine as regular green tea.) Make sure that you steep the tea for at least three minutes…10 is better…so that the L-theanine is extracted.

Try drinking green tea for a few nights, or a few weeks, and if it’s not working for you, here’s how to use an L-theanine supplement…

  • As with all supplements, consult with your doctor before taking it. L-theanine may reduce blood pressure, for example, so if you’re on blood pressure medication, you’ll want to talk with your doctor before taking it.
  • If you decide to take it, try a dose of 200 mg for at least two weeks. You can take it daily or just when you feel you need it or on nights when you don’t have time to drink a cup of green tea.
  • If that dose doesn’t work, you can safely take it as many as three times a day, for a total dosage of 600 mg a day. Don’t worry about taking it during the day. L-theanine may calm you, but it won’t cause drowsiness.
  • If this supplement doesn’t work for you, consider other relaxing ones. Dr. Rubman often prescribes valerian root or 5-HTP to his patients. Try each one separately…on different days…so that you can figure out how each one affects you, and what works best.

To learn more about drug-free ways to improve your sleep, see Bottom Line’s Guide to Better Sleep…No Sleeping Pills Needed.