L-theanine is also present, in lower concentrations, in black tea. There’s less research on the effects of coffee on stress, but researchers have found moderate to high amounts of caffeine are ...
One cup of tea, by contrast, only contains 30 to 50 mg of caffeine. "Generally speaking, coffee has two to three times more caffeine compared to a similar-sized black tea," says Matthew Chow ...
Or do you prefer a slightly less caffeinated nudge from a warm and gentle cup of tea? Whatever your preference, scientists have found that regularly drinking coffee or tea can provide a variety of ...