Religion/Brainwash, is there a difference

Can religion be taken for granted? During the so-called dark ages, we lived to thirty-five years of age. Why this low? The church told the people it was a sin towards God to undress. You were not even allowed to look at your own body. So started many illnesses and a short life. Modern way of living with bathroom in every house has increased our life expectancy. The most ruthless part of religion was when the Inquisition ruled the European, or Catholic church. Of all the war we have had, the religious wars have killed more people than the first and second world-war.