In the herb world there's kind of an inside joke that's basically this- some people are "Blue Vervain" people, meaning they're pretty Type A, love lists and order and control (but often get stressed-out trying to control everything), tend towards holding stress in their bodies- particularly the neck and shoulders- and are often a "work hard, play hard" type. In the Ayurvedic framework these are folks with LOTS of Pitta.

When it comes to the bitter flavor Americans are WAY off their game compared to so many other parts of the world where bitter herbal liquors after meals are the norm. Other than our coffee, which is the main source of bitter in our diets and is actually a perfect example of too much of a good thing (read on to understand this more), our diets are more or less devoid of the bitter flavor.