Did you know that each of your feet contains as many as 250,000 sweat glands? Collectively, these thousands of tiny glands can produce as much as one pint of sweat per foot each day! Human feet host innumerable bacteria that love this concoction of water and sodium. These bacteria, which survive on sweat and dead skin cells, produce the foul odor that make feet stink. More sweat equals more food for bacteria, which in turn produces more bacteria. It’s a perpetuating cycle that can be compounded by how much you sweat, the type of footwear you choose, and the presence of other foot issues like fungal infections.
So while foot odor doesn’t necessarily signify a health problem, in rare instances, it can be a sign of a medical issue. For example, hyperhidrosis, a condition in which one’s sweat glands produce excessive sweat, can lead to excessive odor. Similarly, fungal infections, a very common occurrence, can produce dry, flaky skin that bacteria love to feed on. Both of these issues have potential solutions, so speak to your health care provider if you suspect you may have one of these problems.
Nonmedical issues can also affect foot odor. Footwear made of unbreathable synthetic materials can inhibit the evaporation of sweat and promote the humid environment bacteria love to live in. Socks made of synthetic fabrics can have the same effect. Therefore, to reduce foot odor, it’s best to choose footwear made of natural fabrics (such as cotton). Lastly, good hygiene can make a difference when it comes to foot odor. To reduce your propensity for pungency, dry your feet well after bathing and change socks and shoes regularly. If the problem persists, you might try an over-the-counter foot odor treatment. There are a variety of antibacterial, antifungal, and deodorizing options in spray and powder form that are safe, very effective, and well tolerated by most people.



Why does my sweat smell like cat urine when I wear certain shirts but not others? I have two shirts that make this happen. One is 100% cotton and the other one is probably polyester or poly blend.
Hi Randy
Thanks for your comment. It’s usually not the shirts that are causing the smell, it’s probably your diet. When sweat smells like urine it’s usually from a high protein diet. Your body converts converts excess protein into ammonia when you exercise, and that give your sweat the urine smell. It’s not unhealthy, just unpleasant. I’d suggest lowering the protein content of your diet and substitute for more whole grains, fruits and vegetables which should help the smell go away over time. As always, make sure you talk with your primary care provider before switching up your diet.
Malcolm Thaler, M.D.
Clinical Editor
One Medical Group