Science Questions

I've always wondered what causes your feet to stink. Is it from your feet sweating, or do other things come into play? Josh from Wisconsin

It may shock some people, but your feet actually squirt about half a litre of sweat into your socks and shoes every single day. You also shed in the order of about 40 000 skin cells every minute or so from your body. Over a lifetime that adds up to a few stones in weight of dead skin. Now this is perfect bacterial food, so you have a combination of a warm, damp place with lots of food. This makes your feet a thriving emporium of bacteria and fungi. When these eat the skin in your shoes, they produce volatile substances that smell. It's these substances that come whiffing up to your nose. People who wear trainers a lot end up locking their feet in and let them stew. The way around it is either to use odour eaters or wear sandals, as this lets your feet ventilate. Alternatively, you can wear leather shoes, as this helps your feet breathe more naturally.

October 2005