L-theanine 200 mg
The amino acid in green tea: calm without sedation, and it pairs with your morning coffee.
The short version
What it does It calms without sedating, in under an hour. One of the rare products where you will know quickly whether it suits you.
What it does not do It does not treat established anxiety and does nothing for months of exhaustion. For that, it is ashwagandha or a doctor.
What the studies say
Hidese’s trial tested L-theanine against placebo over four weeks: a drop in perceived stress and in anxiety-related symptoms, with an effect on some cognitive measures too. Theanine is the amino acid in green tea, and it is what explains why tea does not produce coffee’s jitteriness at equal caffeine.
A modest-sized trial, a Japanese population, largely self-reported measures. Nothing allows us to say it replaces proper treatment for anxiety.
Calm without sedation, felt within the hour. It is one of the rare products where you will know fairly quickly whether it suits you.
How to take it
Relevant for a one-off peak — an exam, an interview, public speaking — or if you ruminate in the evening. Also relevant if you want to keep your coffee without the jitters. Not very relevant for exhaustion that has been settling in for months: that is ashwagandha, or a doctor.
200 mg. For a peak: 30 to 60 minutes beforehand. With coffee: at the same time, roughly 2 mg of theanine per 1 mg of caffeine. In the evening: one to two hours before bed.
The effect is judged within the hour, not over weeks. If nothing happens twice in a row, it is not your product.
What is inside
L-theanine. Two origins: extraction from green tea, or production by fermentation. The L form is the active one; D/L blends are less well documented.
Check that the label says “L-theanine” and not just “theanine”. A fermentation-derived form is purer than a tea extract, which also brings caffeine with it.
Green tea extracts sold as theanine: they contain caffeine, which defeats the point of evening use.
Cautions
- Low blood pressure: monitor alongside medication
The three options
Fermentation-derived L-theanine, assayed
200 mg per capsule, 98 % pure
No additives, vegan capsules, 240 units — the exact dose used in the trials. Rejected along the way: a product three times the price, sold as premium, contains only 40 mg of theanine per capsule. You would need five.
For whom — Daily use, sensitivity to excipients.
L-theanine 200 mg in capsules
10,109 reviews, but a gelatin capsule
The largest volume of feedback in the catalogue, 200 mg per capsule. The gelatin makes it non-vegan: if you are, take the option below, in a plant capsule.
For whom — Everyday use, occasional or in the evening.
Large pack
500 mg, vegan, no bulking agent
98 % purity, 180 capsules, neither filler nor anti-caking agent. That is more than the 200 mg used in trials: open the capsule and split it if you want to stay at the tested dose.
For whom — Regular use, tight budget.
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