Description
Stinky feet are possibly the most deadly foot problem you’ll ever encounter. Don’t believe it? Consider this: representatives from two volatile countries meet for peace talks. The moderator, who is wearing too- tight synthetic shoes slips them off under the table to get some relief. Slowly, a malodorous mist wafts up from the depths of the table and into the irascible nostrils of the battling dignitaries. Appalled, one accuses the other of breaking a capsule of poisonous gas. The other representative grows beet-red at the accusation and shouts that if there’s any poisonous gas in the room, it must surely be from the breath of the first representative. A shouting match ensues, during which the moderator, face pale, slips the offending feet back into the tight shoes. Peace breaks down, war reigns, all because of some stinky, smelly feet.

Well. Even if this scenario seems a tiny bit far-fetched, feet that emit unpleasant odors can certainly still be embarrassing and annoying. The bad smell isn’t actually caused by the feet themselves, though: it’s a byproduct of bacteria (or sometimes fungi) that are living on the foot (so if anyone accuses you of having stinky feet, just blame it on the bacteria). In damp, dark conditions (such as the inside of a sweat-soaked shoe), bacteria tend to thrive. They feast on the dead skin cells and oil that come off your skin. Then, they…er…excrete isovaleric acid, which produces an odor human noses tend to regard with disfavor. Reactions with synthetic materials may also contribute to the bad smell. And some particularly unlucky people (usually with extra-sweaty feet) may have bacteria on their feet that emit a sulfurous (rotten egg) smell.

Feet are predisposed to sweat anyway. In fact, the skin of the feet contains more sweat glands than anywhere else, so foot sweat is hardly a novel thing. While pretty much everyone has feet that sweat (unless you have something like neuropathy, but we won’t go into that here), some people have feet that sweat more than usual (hyperhydrosis), making it much more likely that they’ll suffer from unpleasant foot odor (bromhydrosis).

Symptoms
Foot odor symptoms are not exactly easy to miss. If people scramble to leave the room (or even just adopt strange, sort of tight expressions) whenever you take off your shoes, you might have a problem with it. But seriously, a bad odor (malodorous) is one of the main indicators. You may also notice that your feet seem particularly sweaty.

Diagnosis
While smelly feet are pretty easy to notice, your podiatrist may wish to determine why exactly your feet have gotten so smelly. (Bad-smelling feet are rarely, but still occasionally, caused by another condition, such as an overactive thyroid or anaemia.) Your podiatrist may inquire about your stinky history, such as how long malodorous feet have been affecting you, etc. The foot doctor may or may not decide to get a whiff of your feet, depending on the stoutness of his or her constitution, and whether or not he or she has recently had lunch.

Treatment
Fortunately, stinky feet are (despite the introductory example) not likely to be life-threatening, and they’re quite treatable. The key to avoiding bad smells emanating from your feet is to have excellent foot hygiene. You’ll want to wash your feet daily in lukewarm water with mild soap, then dry thoroughly after washing, particularly between your toes to avoid fungal infections. (Fungal infections like athlete’s foot may be more likely to occur if you have particularly sweaty feet.) You can also use foot powders to absorb moisture, although you’ll want to clear the powder away between your toes so it doesn’t gunk them up.

Change your socks daily (more often if your feet become particularly sweaty, such as during sporting activities), and switch shoes daily too. Letting shoes air out for a couple of days after wearing them lets them dry out, preventing bacteria from thriving in them. (And it gives you an excuse to buy an extra pair or two.) Also, avoid shoes that are too tight, or that are made of synthetic materials. Leather, canvas or mesh are materials that will allow your feet to breathe (allowing air to get to your feet and dissipate moisture). You’ll also want to choose socks that wick moisture away from your skin, such as wool (if you don’t react to it) or cotton. Avoid nylon socks or stockings.

You may be able to remove and let your insoles air out, or even take them out and wash them. Disinfectant sprays inside your shoes can kill the bacteria that’s causing the bad smell. Going barefoot (unless you’re diabetic or have other reasons to avoid it) can also help your feet to dry out fully, making it harder for the bacteria on your skin to multiply and excrete that foul odor.

Some people may also find relief from the stink by using antiperspirants such as aluminum chloride hexahydrate, which may be available over the counter or as a prescription. Some stronger measures may include sending an electrical current through the skin (no, DON’T try this at home with your wall socket-if this treatment is available for you, your doctor will have a special machine for it) that often reduces perspiration for a few weeks. If your problem is really severe, you may choose to have a foot surgeon cut the nerve that controls sweating in your foot.