Research library / Sleep

The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic Review

JL Williams, JM Everett, NM D'Cunha, D Sergi, EN Georgousopoulou, RJ Keegan et al.. Plant Foods for Human Nutrition. 2020.

Published 2026-10-15Sources checked 2026-10-151 sourceEverstack research teamHow we work

In plain language

Across 9 randomized trials, 200 to 400 mg a day of L-theanine may help reduce stress and anxiety in people under stressful conditions.

Limits

Small, short trials; authors call for longer and larger studies.

Source

doi.org/10.1007/s11130-019-00771-5 · PubMed 31758301

Summary written by Everstack from the published abstract. Verified against Crossref on 2026-10-15. The authors do not endorse Everstack.