There are many reasons for foot odor, including the following: 1. Consider that because the sole of the foot is a densely distributed area of sweat glands, young adults, especially during strenuous activities, even mental tension, emotional depression, anxiety, may stimulate the sweat glands to secrete large amounts of sweat, and if complicated by bacterial infections, foot odor symptoms are aggravated in hot, humid environments. 2. The foot may be infected with fungus, such as tinea pedis, and the secondary bacterial infection can also cause foot odor to increase. If you have a bacterial infection, you can apply antibacterial ointment to prevent further spread of the infection.