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Mental Health

L-Theanine

Calm without sedation. One of the most underrated daily compounds.

What it is

L-theanine is an amino acid found naturally in green tea. It promotes alpha brain wave activity β€” associated with a relaxed but alert state β€” without causing drowsiness.

Why it matters

Living with a serious diagnosis creates sustained background anxiety. L-theanine takes the edge off that without impairing cognition or creating dependence. It pairs well with caffeine to smooth out the jitteriness of coffee while preserving focus.

The evidence

Multiple RCTs have shown L-theanine reduces subjective anxiety and improves sleep quality at doses of 200–400mg. Meta-analyses confirm the anxiolytic effect is real and dose-dependent.

This information is for educational purposes and does not constitute medical advice. Always discuss supplement use with your care team, particularly if you are undergoing active cancer treatment.

Dosing

200–400mg daily. Can be split morning and evening. Combine with caffeine (2:1 ratio theanine:caffeine) for clean focus.

Cautions

Extremely safe profile. No known serious interactions. May slightly lower blood pressure.

Tags

stress

anxiety

focus

sleep

Buy this supplement

L-Theanine 200mg capsules

Pure L-theanine, 200mg per capsule. No fillers needed. Can combine with coffee at 2:1 theanine:caffeine ratio.

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Evidence-based self-optimisation for people navigating cancer.

Not medical advice. Always work with your care team.

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