green tea should be taken as an antioxidant
while it contains the amino acid l-theanine, eccg's, and other beneficial compounds to reap any benefits you'd have to drink at least 10 cups of tea a day
i get green tea powder (go to chinatown ma man) and make ice tea with it
i also drink it hot
most green tea extracts are decaffienated
not that it contained much caffeine to begin with
other teas are beneficial but to a lesser degree
just enjoy it man
hot or cold
sipping tea tends to relax a mind