This hint is from DoctorOz.com:
It's no wonder that feet smell. As soon as man donned shoes to better traverse the terrain, we prevented the evaporation of a quart of sweat released from thousands of sweat glands each day. Closing up the feet creates a dark, moist, warm environment that bacteria love.
Wear socks made of cotton or other wicking material that can absorb perspiration
Use dehydrating foot powder and footpads that contain activated charcoal that absorbs odor
Use a tea soak 30 minutes every day for a week to allow tea tannins to constrict sweat pores
Go barefoot or wear open sandals when you can
Try adding a few drops of essential oils such as tea tree, sage and clove to a footbath containing arrowroot and baking soda
Rub some rubbing alcohol on feet at bedtime