Stress management
In a detailed study conducted at the Osaka Institute for Health Care Science in Japan, the experimental mice that ingested oolong tea showed a remarkable improvement in their stress levels by 10 to 18 %. The natural polyphenols in the oolong tea was cited as the main cause of it being such a stress-buster. Also, the L-theanine found in tea leaves is an amino acid that blocks L-glutamic acid to glutamate receptors in the brain. This would normally cause cortical neuron excitement, which leads to increased cognitive activity and neural stress responses. Since this amino acid binds to those sites, excitation doesn’t occur, and stress decreases because you are more able to keep your mind at rest.