Pairs with morning caffeine or use it to wind down at night
Pinned to evening, the best window for L-Theanine.
Pairs with morning caffeine or use it to wind down at night
Often paired with caffeine in the morning or used to wind down. Best window is evening, optional food. Educational only, not medical advice.
L-theanine is an amino acid almost unique to tea leaves. It crosses the blood-brain barrier and increases alpha brain waves (the same state seen in alert relaxation and light meditation), elevates GABA, serotonin, and dopamine modestly, and dampens the cortisol response to acute stress without being sedating. That combination is why it pairs so well with caffeine, the caffeine supplies the alertness, the theanine smooths the jittery edge.
Calming amino acid from tea. Pairs with caffeine for focused calm or used alone for relaxation.
Two distinct use cases drive timing. Morning, 200 mg theanine plus 100 mg caffeine for focused calm, the most-studied combination for clean cognitive output. Evening, 100 to 400 mg on its own (no caffeine) for wind-down, 30 to 60 minutes before bed or whenever you need to step out of fight-or-flight. Empty stomach is not required, food slightly slows onset but does not reduce effect. No need to cycle, theanine does not build tolerance.
| Window | Fit | Note |
|---|---|---|
| Morning | Poor | Calming effect works against the day |
| Midday | Okay | Fine if the preferred window is not possible |
| Evening, 1-2h before bed | Best | Aligns with winding down |
Tap each to see why.
Common calming pairing for evenings.
Common cognitive-focus pairing in the morning.
Take together
Suntheanine is a patented, purified L-isomer form with most of the clinical evidence behind it; any reputable brand labeled Suntheanine is a safe bet. Capsules dose precisely (100 or 200 mg), powders let you titrate but taste mildly umami. Avoid mixed D,L-theanine forms, only the L-isomer is bioactive.
| Form | Notes |
|---|---|
| capsule | Standard delivery, neutral taste. |
| powder | Flexible dose, ideal when scaling up gram-level intake. |
Who takes it: Knowledge workers stacking with morning coffee, students under exam stress, people with mild anxiety who want a non-sedating option, and anyone with sleep-onset trouble that responds to relaxation rather than sedation.
Often cited as 2:1 theanine:caffeine (e.g., 200mg theanine + 100mg caffeine).
On the science
The principles behind this guidance, solubility, circadian timing, and spacing, are explained on our science page.
OptimalNourish is strictly educational. We do not recommend dosages, diagnose conditions, or suggest treatments. Always consult a qualified healthcare professional before changing your supplement routine.
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