We’ve all experienced it – taking off our shoes after a long day and getting a whiff of an unpleasant foot odor emanating from our feet. While smelly feet are very common, especially when wearing closed-toe shoes and socks all day, you may wonder what actually causes that smell. In most cases, foot odor is the result of bacteria breaking down dead skin cells on your feet into smelly substances. Here’s a deeper look into what’s really going on when your feet start to stink.
Dead Skin Buildup
Your feet shed a tremendous number of dead skin cells each day – up to 40,000 per foot! Usually this dead skin gets sloughed off naturally as you walk around. However, when your feet are confined inside socks and shoes all day, not all of this dead skin makes it outside. Some of the dead cells accumulate, especially in between the toes and along the edges of the feet. This buildup of dead skin creates additional surface area for bacteria to start growing.
Bacteria Feasting on Dead Skin
There are over 100,000 bacteria living on each foot. Most of these bacteria are harmless types that don’t cause infections. However, these bacteria do produce metabolic waste products as a byproduct of feeding on dead skin cells present on the feet. One substance in particular, isovaleric acid, is responsible for the cheesy odor coming from your feet and footwear. Other smelly byproducts can include propionic acid and butyric acid as well. The more bacteria present breaking down large amounts of dead skin, the more concentrated these odiferous substances become.
Moist Environments Promote Bacteria Growth
Wet conditions promote rapid bacteria overgrowth on the feet. Sweat itself is mostly odorless. But when your feet sweat excessively in enclosed shoes and socks without chances to air out, the warm, damp environment enables bacteria numbers to thrive. The moisture also softens and separates dead skin cells, giving bacteria easier access to food sources. Fungal organisms like yeast and mold can get involved too. All these moisture-loving microbes can produce advanced smelly metabolic byproducts if given suitable conditions.
Other Contributing Factors
There are other secondary causes that can make existing foot odor even worse:
- Poor hygiene – Infrequently washing the feet and wearing the same socks and shoes allows smells to accumulate and intensify over time.
- Hyperhidrosis – Excessive foot sweating, or hyperhidrosis, provides large amounts of sweat for bacteria to feed on and multiply.
- Athlete’s foot – A fungal foot infection breaks down tissues, producing additional food sources for bacteria.
- Shoes & socks – Old shoes, synthetic socks, and inadequate ventilation prevent sweat and smells from escaping.
Improving Smelly Feet
The nostril-assaulting scent coming from your feet is rarely due to poor personal cleanliness alone. Simply washing the feet may temporarily reduce some odors, but the underlying causes will still be present. Successfully controlling foot odor requires attacking the problem from multiple angles with consistent daily effort:
- Wash feet daily – Regular foot washing removes some bacteria and exfoliates off dead skin buildup that bacteria eat. Make sure to dry properly, especially between the toes.
- Rotate shoes daily – This allows shoes to fully dry each day, which helps minimize bacteria overgrowth. Use moisture-wicking shoe inserts as well.
- Wear clean socks – Change socks at least daily to prevent sweat accumulation. Choose breathable cotton or wool socks to reduce excessive moisture.
- Apply foot powder – Antifungal and antibacterial powders create a less-hospitable environment for microbes to grow.
- Consider prescription remedies – Chemical-based wipes, foot soaks, oral medications, Botox injections, and other prescribed treatments may be warranted for excessive foot sweating or fungal infections contributing to smells.
By understanding what’s behind foot odor and attacking it through a multi-pronged hygiene regimen and moisture reduction, most sufferers of smelly feet can achieve noticeable improvement or possible elimination of unwanted odors wafting from down below. Be diligent and proactive with your foot care to prevent that embarrassing moment after shoe removal!