L-Theanine: Calm Focus (Especially With Caffeine)
L-theanine is an amino acid found in tea that promotes a state of "calm alertness" — and it’s one of the few supplements with a genuinely useful, well-liked effect.
What it does
- Promotes relaxation without drowsiness — calm but alert.
- May take the edge off stress and mild anxiety.
- Can support focus and, for some, sleep quality.
It’s naturally in green and black tea, which is part of why tea feels calmer than coffee despite the caffeine.
The caffeine combo
L-theanine’s most popular use is paired with caffeine (a common ratio is ~200 mg theanine to ~100 mg caffeine). Theanine smooths out caffeine’s jitters and crash, giving cleaner, calmer focus — useful before work or a workout. It’s generally well tolerated. As always, check with a doctor if you take medication or have a condition (disclaimer).
Quick answers
What does L-theanine do?
It promotes calm, focused alertness and can ease jitters — especially when combined with caffeine, smoothing out the crash.
Is L-theanine safe?
It’s generally well tolerated for healthy adults. If you take medication or have a health condition, check with your doctor first.
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