Some people couldn’t care less what causes foot odor. They just want to get rid of it. Other people are interested in what causes foot odor precisely because they figure they have a better chance of getting rid of it if they know what causes it. Either way, foot odor is the end result of a chain reaction of events that take place on your feet.
It can happen to people of all ages. I have even heard moms say that one or more of their kids had stinky feet from infancy! It has been a problem throughout the ages ever since people began wearing shoes. Even Roman soldiers had remedies – and they wore sandals!
The human body hosts many species of bacteria, some of which live, thrive, and multiply in a warm, moist environment such your warm sweaty feet snugly encased inside your socks and shoes. Man-made materials such as polyester, nylon, plastic, etc. do not allow for as much ventilation as do natural materials such as cotton, wool, or leather. Therefore enclosing your feet in man-made materials tends to make them sweatier and stinkier.
The bacteria feed on the components of the sweat and the resulting metabolic breakdown produces the characteristic aroma that has been known to clear a room. In other words, it stinks! It should go without saying (but I’ll say it anyway) that the more bacteria there are and the more sweat there is for the bacteria to feed on, the more odor the metabolic breakdown is going to produce.