Many people suffer from smelly feet, while others seem to have odor-free feet no matter what. Why do some people's feet smell worse than others? The answer lies in the complex biology and chemistry that produces foot odor.
The Causes of Smelly Feet
Foot odor is caused by bacteria consuming sweat and producing unpleasant-smelling substances as waste products. Feet contain more sweat glands per square inch than any other part of the body, making them prime real estate for bacteria growth.
The main culprit behind smelly feet is a bacterium called Brevibacterium, which lives naturally on the skin. When feet sweat, these bacteria feast on the sweat and break it down into acidic waste products that have a characteristic cheesy smell.
Another contributor is Propionibacterium, which metabolizes sweat into propionic acid, producing a vinegar-like odor. Other bacteria on the feet produce additional smelly substances like isovaleric acid (smelling like cheese) and methanethiol (smelling like rotten cabbage).
Why do some people have stinkier feet than others then? There are a few key factors at play:
Sweat Production
People who sweat more will nurture larger populations of odor-causing bacteria. Excessive foot sweating, known as hyperhidrosis, is a common cause of foot odor. Certain individuals are just biologically prone to sweating more due to overactive sweat glands.
Foot Hygiene
People who practice poor foot hygiene tend to have smellier feet. Not washing and drying feet properly, wearing the same shoes day after day, and not trimming toenails all provide bacteria more opportunity to multiply and create foot odor.
Genetics
There seems to be a genetic component that predisposes some people to stinky feet. Researchers have found that a gene called ABCC11, which determines your armpit odor, also influences odor in other sweaty areas like the feet. If your parents have smelly feet, you are more likely to have smelly feet as well.
Footwear
Wearing tight, non-breathable shoes like rubber boots day after day traps sweat and bacteria against the feet, creating the perfect conditions for foot odor. In contrast, wearing open toe shoes and taking shoes off periodically gives feet a chance to air out and reduces bacterial buildup.
Medical Conditions
Certain medical conditions can cause excessive foot sweating that worsens odor. These include hyperthyroidism, athlete's foot, toenail fungus, diabetes, and obesity. Treating the underlying condition can help reduce foot odor.
Diet
There is some evidence that strong-smelling foods like garlic, onions, and heavily spiced cuisine can be excreted through sweat and skin secretions, making body and foot odor worse. A diet high in red meat may also worsen BO as meat byproducts are excreted through sweat glands.
Solutions for Addressing Smelly Feet
If you suffer from foot odor, there are several effective remedies to try:
- Wash feet daily with antibacterial soap and dry thoroughly, especially between the toes.
- Apply foot powder and change socks regularly to absorb moisture. Choose moisture-wicking socks.
- Use antifungal spray or powder to prevent athlete's foot fungus which thrives in damp feet.
- Consider prescription antiperspirants for excessive sweating. Oral medications may also be prescribed for hyperhidrosis.
- Use shoe inserts and special ventilated "breathable" shoes that allow airflow. Avoid wearing the same shoes 2 days in a row.
- Soak feet periodically in diluted vinegar or antibacterial solutions like diluted tea tree oil to control bacteria.
- Get into the habit of trimming toenails regularly to prevent buildup of bacteria and fungus underneath.
- Consider laser treatments like MiraDry that disable sweat glands in the feet to reduce sweating and odor long-term.
- Change your diet to avoid foods that may be excreted through sweat and worsen foot odor.
- See a doctor to address any underlying medical conditions that may be contributing to excessive foot sweating and odor.
With some diligent foot care, you can keep foot odor in check. But don't be too hard on yourself as smellier feet for some people may just be an unfortunate genetic inheritance. Be proactive about foot hygiene and manage sweating conditions when necessary. With the right strategy, you can stay comfortable with fresh-smelling feet.
