My feet only recently started to smell. what could have caused this sudden change?

New Shoes or Socks: If you have bought a new shoes it might have been lined with leather that causes your feet to sweat and smell. Same can be said about certains socks that increase sweating. Change them and see if your feet continue to smell. If so then see a podiatrist for further evaluation. Fungal infection of the skin and nails also increases smell in feet.

Change in foot wear: If you recently began wearing shoes with synthetics outer and inner soles, this could increase heat within the shoe. Increased temperature or loss of material breathe ability will increase perspiration resulting in increased odor. Any situation that increases perspiration will result in odor.