Foot odor

Foot odor (or foot odour) is a type of body odor that affects the feet of humans and is generally considered to be an unpleasant smell.

The main cause is foot sweat (also see focal hyperhidrosis). Sweat itself is odorless, but it creates a beneficial environment for certain bacteria to grow and produce bad-smelling substances. These bacteria are naturally present on our skin as part of the human flora (though exponentially more smell is created when closed-toe shoes are worn). The front part of the foot is where it produces the most sweat.Therefore, more smell is created with factors causing more sweating, such as wearing closed-toe shoes for many hours. Socks generally do not cause foot odor on their own, but when worn along with shoes, socks can help to trap the hair on the feet, especially on the toes, and may contribute to the odor's intensity by adding increased surface area in which the bacteria can thrive.

Given that socks directly contact the feet, their composition can affect foot odor. Polyester and nylon are common synthetic materials used to make socks, but generally provide less ventilation than cotton or wool do when used for the same purpose. Wearing polyester or nylon socks may increase the amount of perspiration because they do not let the feet breathe as well as cotton. This may intensify foot odor, although polyester and nylon can help reduce blisters by keeping the perspiration away from the foot. Many synthetic socks are treated with chemicals to help reduce odor. Bamboo fabric socks are naturally anti-microbial, anti bacterial and moisture wicking, cutting odor and abating athletes foot. Since the insides of shoes are typically not washed (unlike socks), and since socks also help to absorb perspiration from feet, wearing closed-toe shoes without socks increases the amount of sweat accumulating in shoes, enabling bacteria to grow over time. Bacterial growth is facilitated in this case because closed-toe shoes do not receive adequate air ventilation (especially in the toe area, where the feet produce the greatest amount of sweat), so the sweat cannot evaporate while the shoe is being worn, in addition to there being no socks to absorb the sweat. Dead skin cells, dirt and oils can also accumulate in the shoe from the foot over time which can increase odor inside the shoe. Mold and fungus are also more likely to form if socks are not worn which can increase odors and other foot issues. If closed-toe shoes (such as ballet flats or pumps) must be worn without socks, the best prevention of foot odor is to slip the shoes off momentarily, at least part-way, whenever the feet start to feel "hot" or sweaty, to allow sweat to evaporate from the feet and shoes. Foot powders are also available to manage moisture and reduce odor.

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