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Some parts of your body, like your feet, get a lot stinkier than others. But it’s not actually your body that stinks. It’s the bacteria (back-TEER-ee-uh) that live on it. Bacteria are tiny living things with only one cell, but together they are powerful. They live all over you, and also inside of you. Some bacteria can make you sick. Other bacteria help you stay healthy. And some bacteria cause you to be smelly—especially the ones that live on your feet.

Feet can get hot and sweaty, especially when they spend a lot of time inside of shoes. Sweat is a good thing, because it helps cool your body down when it’s too hot. Sweat doesn’t have an odor. It is made mostly of water. The problem is, bacteria that live on your feet love wet, warm places. So when your feet sweat, bacteria eat the dead skin and oils that cover your feet and quickly reproduce (REE-pro-DOOSE), or make more bacteria. That’s when things start to get really stinky!

The bacteria on your feet give off gases as they eat. Those gases smell like rotten cheese, sulfur, vinegar, and other sour stuff—eeww! To get rid of those bad odors, you have to cut down on the amount of bacteria on your feet. Wearing clean socks can help. It’s also good to air your shoes out after you wear them. Most importantly, wash your feet with soap and water every day and dry them well. 

To learn more about stinky feet, watch this video from the American Chemical Society.