Test the water, get your feet wet: Taking it slow when trying new things is so common as to be cliche. Doing either, literally, in the wrong footwear, though, can really stink. Smelly feet—known medically as bromodosis—is caused by moisture interacting with bacteria and other microorganisms naturally found on our skin. Potential problems don’t end there. Wet feet can cause outbreaks of nail fungus, athlete’s foot and, in extreme cases, trench foot—a serious condition causing numbness, blisters, and painful cracks or ulcers to develop. Waterproof yet breathable boots are your answer.