Body odor (or B.O., bromhidrosis, osmidrosis or ozochrotia) is a perceived unpleasant smell our bodies can give off when bacteria that live on the skin break down sweat into acids-some say it is the smell of bacteria growing on the body, but it really is the result of bacteria breaking down protein into certain acids.eople who sweat too much-those with hyperhidrosis-may also be susceptible to body odor, however, often the salt level of their sweat is too high for the bacteria to break down-it depends where the excess sweating is occurring and which type of sweat glands are involved.