Is 200 mg of L-theanine too much?
200 milligrams of L-theanine is in the range studies have usually used, 100 to 400 milligrams a day. It has generally been well tolerated in trials.
General information, not medical advice. Check with a doctor or pharmacist before taking a supplement, especially if you are pregnant or breastfeeding, take any medicine, or are under 18.
The figures
| Amount checked | 200 mg |
|---|---|
| Answer | In the range studies used |
| Amounts studies used | 100 to 400 milligrams a day |
Cautions and interactions
- It has generally been well tolerated in trials.
Quick answers
- Is 200 mg of L-theanine too much?
- 200 milligrams of L-theanine is in the range studies have usually used, 100 to 400 milligrams a day. It has generally been well tolerated in trials.
- How much L-theanine do studies use?
- 100 to 400 milligrams a day.
- Is L-theanine safe?
- It has generally been well tolerated in trials.
Sources
- Published review (Frontiers in Nutrition)
https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2026.1922819/full
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