Areas of Focus:

Stress and anxiety 

Study Type:

Systematic Review 

Journal Publication:

National Library Of Medicine/National Centre For Biotechnology Information

Link To Study: 



This study looked at how taking L-theanine, a compound found in green tea, affects stress and anxiety levels in humans. They reviewed 9 scientific articles where people took L-theanine as a supplement and compared it to a control group. They found that taking 200-400 mg of L-theanine per day might help reduce stress and anxiety in people facing stressful situations.

However, they suggest that more research is needed, especially longer studies with larger groups of people, to confirm whether L-theanine can be used as a reliable treatment for reducing stress and anxiety.