After another long and tiring session in the garden yesterday, I slipped off my Wellington Boots and headed straight to the couch for a much needed sit down. My little boy – who was watching television in the same room - temporarily turned his gaze towards me and asked (with a curled up nose), “Daddy, why do your feet smell?” Not the most flattering of questions I thought, but a fair one nonetheless! So what’s the answer? Why do feet smell?

Sweat – and lots of it

Our feet work incredibly hard – just think how many times you stand up, how far you walk or run and how much exercise you do each day. Indeed, most of us subject our feet to pretty much constant pressure throughout our waking hours. It might not be that surprising then – particularly when we know that each foot has a quarter of a million glands - that they can produce up to a pint (0.57 litres) of sweat in a single day. Without this moisture, our skin would quickly become dry and start to crack and make mobility rather painful for us.

But it isn’t the sweat that makes the stink; after all, it is just salt and water. So what does make our feet smell then?

Bacteria – our natural little critters

It is actually the bacteria that live on our skin that produces the odour. Although that doesn’t sound very nice, it is perfectly natural. These bacteria love dark, damp places like socks and shoes and they gorge on the sweat and dead skin cells. The waste they excrete after feasting – in the form of organic acids – is what smells bad. And the more they eat the worse the smell.

For some, feet can be really smelly. Extra sweaty socks and shoes can become a haven for bacteria known as Micrococcus which, in addition to organic acid waste, also excrete horrible smelling sulphur compounds. And many of us know from our schooldays how bad sulphur based things can smell.

Of course, most of us can keep smelly feet in check by regularly cleaning ourselves and changing our socks each morning or after a bout of exercise. If we don’t, the bacteria will continue to multiply...

So there we go. If, like I, you are asked by your inquisitive child why your feet smell, you can now explain!

Sources: How It Works magazine, Kidshealth