Breaking through the misinformation

MSNBC attempts to break through the preconceptions, assumptions, hearsay and misinformation on a whole range of health issues, and is somewhat realistic about how inconclusive the effects of caffeine are.

That said, some effects are without question, as the quote below highlights.

There’s no question that caffeine is a powerful psychoactive drug.  We use it as a mental stimulant (and today the act of drinking coffee in coffee shops has become a social stimulant for conversation, business meetings, and logging onto the Web).  Caffeine prevents sleepiness and sharpens thinking by blocking the action of certain neurotransmitters and lift moods by affecting dopamine.  It “revs you up” by promoting release of adrenaline, starting at doses lower than fifty milligrams, which is about the amount in a serving of black tea or cola.