Table of ContentsView AllTable of ContentsShould I Take Them?L-Theanine and SleepHow Much Do I Need?When Should I Take It?Food SourcesSafety ProfilesOther Supplements for SleepFactors Affecting SleepConsulting a Provider

Table of ContentsView All

View All

Table of Contents

Should I Take Them?

L-Theanine and Sleep

How Much Do I Need?

When Should I Take It?

Food Sources

Safety Profiles

Other Supplements for Sleep

Factors Affecting Sleep

Consulting a Provider

Sleep is essential for health. According to one estimate, roughly 56% of people in the United States experience sleep issues, such as difficulty falling asleep or decreased sleep duration.Poor sleep is linked to an increased risk of health conditions like heart disease and obesity. Sleep deprivation contributes to dangerous accidents and impacts the ability to participate fully in work and social life.

Despite its known benefits, many struggle to get the recommended nightly sleep of seven to nine hours. Many sleep supplements exist, but not all may be effective or safe. Many people have triedL-theaninefor sleep. L-theanine influences neurotransmitters that encourage relaxation and sleepiness.

In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it does for prescription medications. This means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RDN or RD), or pharmacist.

Should I Take L-Theanine for Sleep?

L-theaninesupplements may be beneficial if you have trouble falling asleep or experience poor sleep quality. L-theanine does not induce sleep. Instead, they encourage relaxation topromote sleep.

L-theanine acts onglutamatereceptors in the central nervous system. Glutamate is a neurotransmitter that supports numerous functions in the body. L-theanine potentially blocks glutamate receptors to promote relaxation.

Preliminary studies in mice show that acombined supplement of L-theanine and magnesiumincreases sleep duration and reduces sleep disturbances.Still, more research in humans is needed.

It is also vital that you discuss any sleep concerns with your healthcare provider to rule out issues such as sleep apnea, chronic insomnia from depression or anxiety, mineral deficiencies (e.g., iron), and more.

L-Theanine’s Sleep Benefits

L-theanine is a protein (amino acid) found naturally in tea leaves. It is responsible for the flavor ofgreen tea.

L-theanine does not directly induce sleep. Instead, it reduces anxiety and stress and encourages relaxation, which helps facilitate sleep.

L-theanine for sleep has two effects. It acts on neurons and influences brain wave activity to promote relaxation and reduce stress and anxiety.It influencesgamma-aminobutyricacid receptors(GABA), a neurotransmitter that helps you relax.

L-theanine enhances sleep quality. It does not increase sleep duration but may reduce any bouts of wakefulness during the night. However, L-theanine boosts fatigue recovery and helps you feel refreshed upon awakening.

Unlike other sleep aids, L-theanine does not cause daytime drowsiness.Additionally, it may minimize the adverse effects ofcaffeine on sleep.

Taking GABA and L-Theanine for Stress

Always speak with your healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs.

The following dosages for L-theanine for sleep have been studied in clinical trials, but they should not replace your healthcare provider’s recommendations:

Age and past medical history may also influence how much sleep you need. Consult your healthcare provider to determine the appropriate dose for you.

There is an ideal time of day to take L-theanine, including the following:

If you find that changing the timing of your supplement works better for you, it may be ok to do so. However, be sure to discuss this with your healthcare provider.

Food Sources of L-Theanine

Tea is a significant natural source of L-theanine, with a content of about 0.5 to 2.5% in tea leaves. Since L-theanine is water-soluble, nearly all the theanine in the tea leaves will dissolve, resulting in 3 to 5 grams per mug. Matcha is a particularly potent source of L-theanine due to its processing methods.However, tea and matcha also contain caffeine, so it may not be ideal to ingest them before bed for sleep.

Is L-Theanine Safe for Me?

What Other Supplements Work for Sleep?

Other supplements besides L-theanine may benefit sleep, including the following:

Factors That Affect Sleep Quality

When to Consult Your Healthcare Provider

The occasional night of suboptimal sleep may not be cause for concern. However, chronic sleeplessness can be a sign of a more serious health condition. Moreover, consistently poor sleep can increase the risk of other health conditions, such as heart disease, diabetes, or depression.

Sleep issues may be compounded during certain situations. These include having young children, caring for people who are chronically ill, or working late shifts.

Consider talking with your healthcare provider if you repeatedly have trouble falling asleep, staying asleep, or are extremely sleepy during the day. Also, speak with your healthcare provider if you need support for yourself or your family during times of heightened stress.

Summary

Good sleep is essential for health. L-theanine supplements may improve sleep quality and reduce the time it takes to fall asleep.

For most people, L-theanine is relatively safe to take. Adding L-theanine supplements to your routine may provide the support you need for better sleep.

25 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Dasdelen MF, Er S, Kaplan B, et al.A novel theanine complex, Mg-L-theanine improves sleep qualityviaregulating brain electrochemical activity.Front Nutr. 2022;9:874254. doi:10.3389/fnut.2022.874254

PubChem.Theanine.

Rao TP, Ozeki M, Juneja LR.In search of a safe natural sleep aid.J Am Coll Nutr. 2015;34(5):436-447. doi:10.1080/07315724.2014.926153

Perini M, Pianezze S, Ziller L, et al.Characterization of L-theanine in tea extracts and synthetic products using stable isotope ratio analysis.J Food Drug Anal. 2021;29(2):311-318. Published 2021 Jun 15. doi:10.38212/2224-6614.3349

Hidese S, Ogawa S, Ota M, et al.Effects of L-theanine administration on stress-related symptoms and cognitive functions in healthy adults: a randomized controlled trial.Nutrients. 2019;11(10):2362. doi:10.3390/nu11102362

U.S. Food and Drug Administration.GRAS notices l-theanine.

The American College of Obstetricians and Gynecologists.Moderate caffeine consumption during pregnancy.

Lyon MR, Kapoor MP, Juneja LR.The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial.Altern Med Rev. 2011;16(4):348-354.

Türközü D, Şanlier N.L-theanine, unique amino acid of tea, and its metabolism, health effects, and safety.Crit Rev Food Sci Nutr. 2017;57(8):1681-1687. doi:10.1080/10408398.2015.1016141

National Institute of Health Office of Dietary Supplements.Ashwagandha: Is it helpful for stress, anxiety, or sleep?

National Institute of Health National Center for Complementary and Integrative Health.Ashwagandha.

Bruni O, Ferini-Strambi L, Giacomoni E, Pellegrino P.Herbal remedies and their possible effect on the gabaergic system and sleep.Nutrients. 2021;13(2):530. Published 2021 Feb 6. doi:10.3390/nu13020530

Fatemeh G, Sajjad M, Niloufar R, et al.Effect of melatonin supplementation on sleep quality: a systematic review and meta-analysis of randomized controlled trials.J Neurol. 2022;269(1):205-216. doi:10.1007/s00415-020-10381-w

National Institute of Health National Center for Complementary and Integrative Health.Melatonin: what you need to know.

Bent S, Padula A, Moore D, et al.Valerian for sleep: a systematic review and meta-analysis.Am J Med. 2006;119(12):1005-1012. doi:10.1016/j.amjmed.2006.02.026

National Institute of Health National Center for Complementary and Integrative Health.Valerian.

Drake C, Roehrs T, Shambroom J, et al.Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed.J Clin Sleep Med. 2013;9(11):1195-1200. doi:10.5664/jcsm.3170

U.S. Department of Agriculture.Beverages, coffee, brewed, breakfast blend.

Chaudhary NS, Grandner MA, Jackson NJ, et al.Caffeine consumption, insomnia, and sleep duration: results from a nationally representative sample.Nutrition. 2016;32(11-12):1193-1199. doi:10.1016/j.nut.2016.04.005

Alnawwar MA, Alraddadi MI, Algethmi RA, et al.The effect of physical activity on sleep quality and sleep disorder: a systematic review.Cureus. 2023;15(8):e43595. doi:10.7759/cureus.43595

He S, Hasler BP, Chakravorty S.Alcohol and sleep-related problems.Curr Opin Psychol. 2019;30:117-122. doi:10.1016/j.copsyc.2019.03.007

Centers for Disease Control and Prevention.Improve sleep: tips to improve your sleep when times are tough.

The National Council on Aging.Substances and sleep: how prescription drugs and stimulants disrupt your sleep.

The National Sleep Foundation.Not sleeping well? It might be time to see a healthcare provider.

Meet Our Medical Expert Board

Share Feedback

Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit

Was this page helpful?

Thanks for your feedback!

What is your feedback?OtherHelpfulReport an ErrorSubmit

What is your feedback?