My heels are so dry they’re cracking and catching on socks. What causes this?

When your heels crack, the skin on your feet has become excessively dry and thickened. This thickening, known as callus formation, occurs as a protective response to pressure and friction. The skin loses its elasticity and becomes rigid, which makes it more susceptible to cracking under pressure. These cracks, or fissures, can be superficial or deep, depending on the severity of the dryness and the thickness of the callus.

The average thickness of callused skin on the heel can range from 1 to 3 millimeters, while healthy skin is typically around 0.5 millimeters. When the skin loses its natural moisture content, which normally ranges between 10-30%, it becomes less pliable and more prone to splitting. This is why maintaining adequate hydration in the skin is crucial to prevent cracking.

The heels are particularly prone to dryness and cracking due to their structure and function. They bear the brunt of the body’s weight and are under constant pressure, especially during walking and standing. This pressure can cause the skin to expand sideways, leading to cracking.