Do you stress out going through airport security? Can’t stand going to your best friend’s house because you have to leave your shoes at the door? Would it make you feel a little better to know that technically it’s not you that smells disgusting? Let’s get into the chemistry of why your feet reek. (Reactions Splash Intro) To understand how your feet produce those nasty odors, first we’ve got to talk sweat. Your body is covered in glands that secrete sweat in order to cool you down. There are spots on your body that have much higher concentrations of sweat glands, your feet being number one of the list. Sweat is actually odorless on its own, but it plays an integral role in fueling the stench. Shoes and socks don’t leave much breathing room for your feet, which trap in all that sweaty moisture – all the better for a bacterial family to settle down and start a life, but they do have other specific criteria to check off a list first. The best environment for bacterial growth involves these four qualities: Your feet are warm. They’re sweaty. There’s oxygen getting into your shoes, and the dead skin on your feet is a nutrient buffet for bacteria. And when these bacteria feast, they spit out nasty gases – the main culprit of your stinky feet. These are the three main stinky bacterial waste products. (Text onscreen – Methanethiol, propanoic
acid, isovaleric acid). Methanethiol makes your feet smell like sulfur And is produced when dead skin is eaten up by a genus of bacteria called brevibacteria. This stuff smells similar to a limburger or munster cheese. Nice. Isovaleric acid is another compound that shares the cheesy aroma, along with a sort
of rancid, vinegar-like scent. Isovaleric acid is produced when a bacteria
called Staphylococcus epidermis chow down on your dead skin. Propanoic acid adds a rancid, sour smell and is produced by propionibacterium when it gobbles up amino acids found in your sweat. Every time you put your shoes on, you basically refuel these three odor -causing bacteria and perpetuate the stinky feet cycle. So here’s what you need to do to get
a grip on odor control. You want to target sweat, dead skin, and
the bacteria they support. You can wash your feet with antibacterial soap and also use a pumice stone to remove dead skin – cutting out that bacterial food supply. Obviously, use fresh socks daily, and also make sure they’re made of a breathable, natural material like cotton to let moisture out. When you take your shoes off, let them air out and try to keep them dry. To keep your feet dry, you can actually use the same antiperspirant that you use for your underarms. Follow these steps, and kiss your foot shame goodbye. On the topic of smells, check out this video on why garlic gives you bad breath. Also we’ve got this interesting one
on human pheromones. Thanks for watching folks, make sure to hit the subscribe button on the way out, give us a quick thumbs up and hit us with your chemistry questions in the comments. We’ll see you again very soon.