Here's some data from various sources regarding caffeine levels in different types of tea, and also some data about extraction: Theanine and Caffeine Content o

Here's some data from various sources regarding caffeine levels in different types of tea, and also some data about extraction: Theanine and Caffeine Content of Infusions Prepared from Commercial Tea Samples https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4787341/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4787341/ Caffeine in Tea Revisited http://teaintheancientworld.blogspot.com/2017/06/caffeine-in-tea-revisited.html http://teaintheancientworld.blogspot.com/2017/06/caffeine-in... Caffeine Content in 39 Tea Samples https://www.teaguardian.com/tea-health/caffeine-content-39-tea-samples/ https://www.teaguardian.com/tea-health/caffeine-content-39-t... 90% of the tea I drink is loose-leaf, and I'm sure there are definite differences between loose and tea bags, because tea bags very often have very fine almost tea "dust" instead of actual leaves, and the increased surface area makes it extract faster. The psychoactive effects you are talking about are likely a result of L-Theanine, if I had to guess