For most people, putting on deodorant is a necessary ritual on par with brushing teeth or washing hands. But for those who produce no armpit stench, it is totally unnecessary.Despite that, more than three-quarters of those people still use deodorant at least once a week, a new study finds.The findings, published in the latest issue of the Journal of Investigative Dermatology, show just how much a person's daily life is dictated by what's considered normal."They're spending their money, exposing their skin to what may in a few instances not be good for their skin. It sort of suggests to me that there are a lot of conformists around," said study co-author Ian Day, a genetic epidemiologist at the University of Bristol