It is surprising how much chemistry goes into understanding basic biology.
Considering a simple cup of tea. There have been many studies showing the important bioactive compounds in tea. Catechins are polyphenols that got significant attention for their anti-oxidant activities. Then there is caffeine. But another component L-theanine has not been discussed much.
L-theanine is found in teas and metabolizes to form L-glutamine and ethylamine. It is thought that the glutamine can have a pharmacological effect in the brain. There have been studies that have shown that having tea causes an effect on EEG and induces alpha rhythm (Juneja et al. Trends in Food Science & Tech 1999;10;199-204). This was a small study with L-theanine (n=16) vs placebo (n=19) and the difference was significant increase in alpha activity (p=0.05).
But studies like this encourage so many patients to take so many medications that many of the large hospitals have created webpages to educate. Look at this example from a cancer hospital in New York City:
https://www.mskcc.org/cancer-care/integrative-medicine/herbs/l-theanine
Many more studies will be required to educate but in the meanwhile many people continue to drink tea’s for taste and health benefits
