When we walk or stand, our body weight is carried first on the heel and then on the ball of the foot, where the skin is thicker, to withstand the pressure. When this pressure becomes excessive, some areas of the skin thicken, in the form of corns and callus, as a protective response. A callus, or callosity, is an extended area of thickened skin on the soles of the feet, and occurs on areas of pressure. It is the body's reaction to pressure or friction, and can appear anywhere the skin rubs against a bone, a shoe, or the ground. Most calluses are symptoms of an underlying problem like a bony deformity, a particular style of walking, or inappropriate footwear.
Some people have a natural tendency to form callus because of their skin type.
You can control a small amount of hard skin by gently rubbing with a pumice stone, or chiropody sponge occasionally when you are in the bath. Use a moisturising cream daily. Your chiropodist can also remove hard skin, relieve pain, and redistribute pressure with soft padding, strapping, or corrective appliances which fit easily into your shoes. The skin should then return to its normal state. The elderly can benefit from padding to the ball of the foot, to compensate for any loss of natural padding.