Calluses are layers of hardened skin that develop in response to friction and impact. They are common on your feet and can vary in thickness based on genetics, where and how you walk or the shoes you wear. Calluses are important because they protect your feet from pain and injury. Without calluses, your feet could develop blisters or sores that could cause you to change your stride to avoid putting pressure on those tender spots. In the long term, this could lead to bigger problems like ankle, knee or back misalignment. So, please remember to be gentle when you're smoothing your calluses. It's great to have soft, smooth feet. But don't overdo it. Keep a healthy layer of protective callusing on your feet and minimize build up by choosing footwear that fits properly.