Why do my feet smell like vinegar?

Even when we think we're alone, we're actually outnumbered by as much as two to one. That's because, according to the BBC, of our total body cell count, our actual cells make up only 43 percent — with the rest made up of colonies (and more colonies) of bacteria, viruses, and fungi. While this info may make you rethink your personal hygiene routine, most of these microorganisms are totally normal. However, getting to know these little guys is probably a good idea, as they can give you clues about what's going on with your body.  

A fourth microorganism, archaea, can also be found on our feet — these are very similar to bacteria and have been mistaken for them in the past, but archaea behave in a different way: for instance, they produce methane, which is pretty unique among microorganisms (via Science.org). While a majority of these micro-colonies live inside our gut, a fair number of them can be found in more moist surface areas of the skin, like the armpits, side of the groin, the navel, and the bottom of your feet (via Wired). 

Thanks to the type of microorganisms that live on our soles and the kind of gases they produce, Discover Magazine says we can expect our feet to smell like one of four different things: cheese (when bacteria produces methanethiol), sweat (when they produce isovaleric acid), cabbage (when microbes produce propionic acid and butyric acid), and vinegar (when they produce acetic acid).

Why smelling your own feet is important

While we may not think of smelling our feet as a pleasant activity, Discover Magazine says it is important to take a whiff every now and then, because a change in the odor could also indicate a change in the type of colonies that off our feet. Bacteria are considered good microbes, because they feast off dead skin cells, keep our skin soft, and act as a defense shield against pathogens who are more interested in live flesh. A smell change, particularly one that tends to be sour or bready, could indicate that an infection that triggers rashes and wounds could be just around the corner. 

Cleveland Clinic podiatrist Joy Rowland says foot infections can be headed off by soaking your feet thoroughly in warm water with half a cup of Epsom salts for 10 to 20 minutes. An alternative to a soak with Epsom salts is a warm vinegar soak with two parts water and one part vinegar; both foot baths pull moisture away from your feet, making them less hospitable to hostile microbes (vinegar, incidentally, is one heck of a handy all-purpose substance to keep around your house — you can even clean your toilet with it). 

Rowland also says it is important to dry your feet properly after a shower (get into those creases!), disinfect your shoes properly, and use a bit of corn starch or talcum powder to make sure the moisture produced by the glands on the soles of your feet is kept under control. 

So, if your feet smell like vinegar, that's not necessarily a cause for concern — it's just a natural by-product of the little creatures that hang around on your feet. It definitely could be worse, so keep sniffing your feet every now and then to see if there is a significant change so you can take care of it ASAP. And as always, if you're concerned, make an appointment with your doctor.