Feet smell due to the overgrowth of bacteria.
More Info: Sweaty feet are the source of foot odor. Each foot has more than 250,000 sweat glands able to produce up to a pint of sweat per day. However, it’s not the sweat itself that smells. It is the natural bacteria present on your body feeding on that sweat that produce an odor.
Your Feet Are a Breeding Ground for Bacteria
The hands have nearly as many sweat glands as the feet, so why don’t the hands smell? On the hands, the sweat does not accumulate and invite an overgrowth of bacteria. It simply dissipates. The conditions that a sock and a shoe create cause the problem. Bacteria multiply when conditions are dark, warm, and moist– the exact conditions created by a sweaty foot inside of a pair of shoes and socks. Some bacteria is good, an overgrowth can cause problems.
Your Feet Are Fermenting
Feet smell because they are fermenting. Fermentation is the process by which an organism breaks down a substance and then produces a byproduct. In the case of smelly feet, bacterial colonies feed on the waste material in sweat and produce a byproduct of organic acid, which produces an odor. In the case of foot odor, one of the culprits could be Micrococcus, which is commonly found on mammalian skin and in the soil.
How Do I Get Rid of the Body’s Bacteria?
Good hygiene is important for overall health, but even the most vigilante hygienic practices will not remove all bacteria from your body. The human body is a virtual microbiome of bacteria. In fact, researchers have identified more than 10,000 microbial species that coexist within the human body. Though as a society many think of bacteria as an organism that will make us sick, many bacteria are beneficial and even necessary to human life. The bacteria in the gastrointestinal tract, for example, are responsible for processing the food we eat. Without it, we would not be able to fully digest food and absorb its nutrients.
If All Humans Carry Bacteria, why do Some Feet Smell More Than Others?
All things being equal, such as good hygienic practices. . .
Sweating is the body’s manner of cooling itself when it becomes heated in response to external heat, exertion, or even nerve stimulation. Individuals have natural variations in how their body’s sweat. Some people just naturally sweat more than others do. This fact, coupled with the fact some people are more physically active and some are more highly reactive to stressful situations, means that some people are going to naturally sweat more than others do. Excessive sweating, or hyperhidrosis, could be a sign of an underlying medical condition.
Additionally, every individual has bacterial communities unique to him or her. A group of researchers from CU Boulder and the Washington University School of Medicine demonstrated this fact as well as the fact that these personalized bacterial communities vary widely from one area of the body to another.
So Smelly Feet Are a Lost Cause?
Just because you sweat more doesn’t mean that you have to give in to smelly feet. You just need to work harder at preventing the problem. Your key point of focus is to inhibit the growth of bacteria by keeping your feet, socks, and shoes dry. This means never wearing shoes without absorbent socks and never wearing wet shoes. Use a foot deodorizer just as you would an antiperspirant. It will help to control the odor and the smell. To make your shoes last longer, purchase odor absorbent insoles that can be replaced as often as needed.
Clausen, University of Arkansas Research Frontier
Why Do Feet Stink?
University of Wisconsin-Microbiology Laboratories
An Introduction to Lactic Acid Bacteria
Is Your Excessive Sweating Caused by a Medical Problem?
University of Colorado Boulder
Normal bacterial makeup of the body has huge implications for health, says CU-Boulder professor
Marshall, Journal of Applied Bacteriology
A comparative study of the cutaneous microflora of normal feet with low and high levels of odour
1988; Volume: 65; No: 1; Pages 61-68