L‑Theanine
L‑Theanine
Snapshot
L‑Theanine is a unique amino acid in tea that boosts calm focus, eases stress, and enhances sleep quality without sedation.
What is L‑Theanine?
L‑Theanine (γ‑ethylamino‑L‑glutamate) is a non‑protein amino acid in Camellia sinensis leaves. It crosses the blood–brain barrier to modulate neurotransmitters, delivering relaxed alertness.
Where It Comes From
Naturally found in green, black, and white teas and some edible mushrooms, L‑Theanine is also manufactured for supplements in powder or capsule form.
Key Nutrients & Compounds
L‑Theanine itself facilitates GABA, glutamate, and dopamine balance in the brain and synergizes with caffeine to smooth out energy and improve cognition.
Health Benefits
L‑Theanine calms mental and physical stress without drowsiness; sharpens attention and multitasking; counteracts caffeine jitters; and promotes deeper, more restorative sleep.
Recommended Dosage
100–200 mg one to two times daily for stress relief or cognitive support; doses up to 400 mg/day are well tolerated; take 30–60 minutes before focus‑intensive tasks or bedtime.
How to Use It
Take L‑Theanine with water, tea, or a light snack. Combining it with caffeine sources yields balanced focus and energy.
Who Should Use It?
Ideal for individuals seeking stress management, enhanced concentration, smoother caffeine energy, or improved sleep patterns.
Possible Interactions or Cautions
Generally safe; high doses may cause mild headache or stomach discomfort. Consult a healthcare provider if on antihypertensive or psychoactive medications.
Final Thoughts
L‑Theanine offers a relaxing yet alert mental state, making it a versatile ally for stress relief, cognitive performance, and sleep support.
Scientific Studies
Kimura K, Ozeki M, Juneja LR, Ohira H. L‑Theanine reduces psychological and physiological stress responses. Biol Psychol. 2007;74(1):39–45. https://doi.org/10.1016/j.biopsycho.2006.06.006
Haskell CF, Kennedy DO, Milne AL, Wesnes KA, Scholey AB. The effects of L‑Theanine, caffeine and their combination on cognition and mood. Biol Psychol. 2008;77(2):113–122. https://doi.org/10.1016/j.biopsycho.2007.09.008
Juneja LR, Chu DC, Okubo T, Nagato Y, Yokogoshi H. L‑Theanine—a unique amino acid of green tea and its relaxation effect in humans. Trends Food Sci Technol. 1999;10(6–7):199–204. https://doi.org/10.1016/S0924-2244(00)00087-6