From your link:
” Caffeine is not only a habit forming drug but it is destructive to the tissues of the stomach, eyes, nerves and kidneys. In fact there is not a part of the body that is not injured by this drug.”
It is nice to see someone is actually going to links and doing a little reading. :-)
Since the human body is extremely complex, so is determining what aids or hurts health. Sometimes it is a matter of degrees, sometimes it is not.
Just for clarification, the scientific theory behind vaccines is, I believe, very valid. The implementation, with animal parts, dangerous preservatives, failure to handle allergies before hand, insufficiently inactivated biohazards etc., make it like roulette.