All you can do is try your best

How do you talk to people like this?

And you might remind them that the science of today is often the quackery of tomorrow and ask them exactly when did God and Nature become quacks.

At any point in history most people believe that the science and common beliefs are the ultimate truth and that all that came before was backwards and wrong, without stopping to think that one day their science and beliefs will likely be relegated to past and also considered outdated and disproven.  For centuries man believed that the world was flat and the sun revolved around it.

God and nature remain true - despite man's pathetic attempts to corrupt and surpass them.

And tell those would-be researchers to come join us here at CureZone with open minds and eyes (and stay out of the damned debate forums! - lol)