Basics
Caffeine and L-theanine: why they are paired
If you have ever wondered why a strong cup of green tea feels calmer than a coffee with the same caffeine in it, L-theanine is a large part of the answer.
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- ZOMBIE editorial
- Published
- Last reviewed
- Reading time
- 5 min read
What it is
L-theanine is an amino acid found almost exclusively in tea leaves. It is not a stimulant and it is not a sedative. On its own, at the doses used here, most people notice very little.
Its interest is entirely in combination. Caffeine at 100mg and above produces, in a lot of people, a physical restlessness — the hands, the jaw, the sense of being wound slightly too tight. Theanine reduces that without reducing the alertness caffeine is there to provide.
Why 1:1
The ratios used in the research on this pairing cluster around 1:1 and 2:1 theanine to caffeine. We use 1:1 — 100mg of theanine alongside 100mg of caffeine, 50 with 50, 150 with 150.
The reason for matching the ratio to the dose rather than fixing a number is that the thing you are counteracting scales with the caffeine. A fixed 100mg of theanine would be over-specified in a 50mg pouch and under-specified in a 150mg one.
What it does not do
It is worth being precise, because this ingredient attracts a lot of overclaiming.
- It does not stop caffeine keeping you awake. The half-life is unchanged. A 4pm pouch is still a 4pm pouch.
- It does not make a large dose safe. 150mg with theanine is still 150mg.
- It is not a nootropic in the sense of making you smarter. The effect is on the texture of the caffeine, not on cognition in isolation.
- It will not do much if you are someone who has never found caffeine jittery in the first place.
What you should expect
Subtle, and most noticeable at the higher doses. If you take a 150mg pouch and compare it to 150mg of caffeine from any source without theanine, the difference is in how the peak feels — flatter, less physically busy — rather than in how alert you are.
It is a refinement, not a headline. We include it because the alternative is selling concentrated caffeine on its own, and that is a worse product.
Sources
This guide is general information about caffeine, not medical advice. If you are pregnant, breastfeeding, under 18, taking medication or living with a heart or anxiety condition, speak to a pharmacist or GP before using concentrated caffeine products.