There’s no shortage of people who are looking to improve their sleep hygiene, manage everyday highs and lows, and stay focused during busy days. And, luckily, there’s no shortage of supplements promising to help out in these areas. But which ones will go the distance and really do what they say?
We’ve already confirmed the legitimacy of magnesium glycinate for sleep and stress management, as well as adaptogens for energy and nootropics for cognitive function. Now, we’re here to tell you that l-theanine is a triple-threat for supporting focus, mood, and sleep.
Found in tea and certain mushrooms, you may already unknowingly consume this natural compound here and there, but l-theanine supplements can be a worthy addition to many a wellness routine. Here, experts break down the mega benefits of l-theanine and pro tips for adding it to your regimen.
- ABOUT OUR EXPERTS: Shivani Amin, M.D., is a functional medicine physician. Gowri Reddy Rocco, M.D., is a physician double-board certified in family medicine and regenerative, anti-aging, and functional medicine.
What Is L-theanine?
L-theanine is an amino acid primarily found in certain plant and fungal species. It’s particularly well-known for being a significant component of green and black tea leaves, says Gowri Reddy Rocco, M.D., a physician double-board certified family medicine and regenerative, anti-aging, and functional medicine. “Unlike many other amino acids, l-theanine is not used to build proteins, but is prized for its potential impact on mental functioning,” she explains. It’s structurally similar to glutamate, a neurotransmitter related to memory and learning, which allows it to exert unique effects on the brain, she adds.
How L-theanine Can Support Your Health And Wellness
L-theanine has some pretty unique benefits that make it a particularly powerful supplement. Here are the many ways it can nourish your mind and body.
1. Promotes Relaxation And Healthy Mood
L-theanine may help reduce stress and feelings of anxiety by increasing “feel-good” neurotransmitters like serotonin and dopamine in the brain, helping to improve mood and promote relaxation, says Rocco. “The amino acid and antioxidant easily crosses the blood-brain barrier to promote alpha brain waves that induce calmness, so you feel relaxed yet alert without drowsiness,” she explains.
The compound also helps ease feelings of anxiety since it plays a role in the creation of gamma-aminobutyric acid (GABA) receptors, says functional medicine physician Shivani Amin, M.D. GABA is a chemical messenger in your brain that helps control nerve cell hyperactivity associated with anxiety, stress, and fear—and by increasing receptors for it, l-theanine can have a relaxing effect, she explains.
2. Sharpens Focus
Not only does this powerful amino acid chill you out, but l-theanine can also enhance the brain’s ability to learn and focus. “By potentially enhancing the activity of alpha brain waves, which are associated with a state of wakeful relaxation, l-theanine can promote better focus and attention,” explains Rocco. “This effect is particularly noted when l-theanine is consumed with caffeine, as it is in tea, which can synergistically enhance alertness and focus.”
Read More: 6 Possible Culprits Behind Your Brain Fog
Also worth noting: L-theanine does not stimulate theta or delta waves in the brain, which trigger deep sleep and drowsiness, so it can be taken during the day to up your focus without making you sleepy, according to Rocco. “You stay alert, productive, and in control,” she says.
3. Supports Better Sleep
Although l-theanine does not induce drowsiness, it can improve sleep quality via its relaxing and mood-balancing effects, according to Amin. You might notice you fall asleep quicker and have fewer disturbances throughout the night. Studies have confirmed that l-theanine safely supports sleep by boosting slow-brain waves, regulating brain electrical activity, and increasing neurotransmitter and GABA receptor levels
4. Promotes Robust Immunity
Some research suggests that l-theanine may help boost your immunity by regulating immune responses and supporting the body’s defenses against offenders like the common cold, Rocco says. More research is needed here, but some early research suggests that l-theanine may promote a healthy immune system through its antioxidant effects and benefits for both the nervous and digestive systems.
5. Supports Brain Health
Research is still in the works, but l-theanine may have neuroprotective benefits, potentially supporting long-term brain health and function, in addition to boosting cognition, suggests Rocco. “This effect is thought to be related to its antioxidant properties and its ability to modulate neurotransmitter levels,” she says. Studies also support that l-theanine contributes to improved attention, ultimately enhancing working memory and executive brain function.
6. Encourages Healthy Blood Pressure
Thanks to l-theanine’s calming effects, the amino acid can support healthy blood pressure, particularly in stressful situations—and there’s research to prove it, says Rocco. (Just note that, for this reason, anyone taking blood pressure medications should talk to their doctor before supplementing with l-theanine.)
Should You Try L-theanine?
L-theanine is generally considered safe for long-term use with no known severe side effects, according to Amin. (Some might experience nausea or sleepiness when taking high doses.) This means that most people can give it a go! However, those who are pregnant or breastfeeding and those taking any medications should get the green light from their doctor first. L-theanine should not be taken with blood pressure medications or sleep aids/sedatives since drug interactions can cause slowed breathing, says Rocco.
Tips For Adding L-theanine To Your Routine
1. Consult With Your Provider First
Before starting l-theanine (or any new supplement), Amin recommends checking in with your doctor. This is especially important if you currently take prescription blood pressure medications, sleep aids, or are pregnant and/or breastfeeding, adds Rocco.
2. Prioritize Quality
As with all vitamins and supplements, you should always buy l-theanine from a reputable source, like a health food store or specialty supplement shop, suggests Rocco. (Hello, The Vitamin Shoppe!) These retailers are most likely to offer top-notch products free from fillers and undesirable additives like gluten. Read: Random websites are not the move!
To ensure quality and purity, Amin also recommends looking for a product that has been third-party tested. This means an unbiased party has confirmed the product contains only the ingredients it lists on the label and in the amounts stated.
3. Dose Appropriately
L-theanine can be taken with or without food, either in the morning or early afternoon to enhance daytime relation and focus, or in the evening to promote quality sleep, Amin suggests.
When it comes to dosing, Rocco recommends the following:
For a calm mind and/or focus: Start with 200 to 400 milligrams twice per day (in the morning and evening).
For sleep: Start with 100 milligrams 30 to 40 minutes before bedtime. If you don’t notice any effects, increase to 200 milligrams.
You’ll find l-theanine supplements capsule, gummy, liquid, or powder form—and which method you choose is up to you, Amin says. If you want to stick to capsules, check out The Vitamin Shoppe brand L-theanine (200 milligrams). Or, mix it up with MaryRuth’s Strawberry Melatonin-Free Sleep Gummies or Winged Chilled Out Relaxation Drink Mix Powder.