What Causes Calluses?

Why does this tissue layer build up in only certain locations? On the simplest level, skin is capable of doing only two things: growing or breaking down. Our skin is constantly regenerating itself, and the regeneration of new skin and sloughing of old skin cells is a perpetual process over the entire body. What is unique in corn and callus formation is that the outer layer of skin is growing at a much more rapid rate than the skin around it. The reason for this, again, is that there is increased pressure in those areas. Consider the calluses we get on our hands from repetitive activities like shoveling or lifting weights. These are the result of repeated pressures in specific locations over time. A callus is the body's way of laying down a stronger, thicker layer of skin in a location that is subjected to a more demanding share of the workload. These calluses are different than the blisters we get the same day we "surprise" our bodies unusual amounts of repetitive skin pressure or shear over a short time. A blister is the result of skin tissue breakdown before a protective callus has had time to be produced. Consider the lumberjack chopping wood; he may have had blisters his first week on the job, but the tough-as-leather hands he has now are the result of his body adjusting to the stress by laying down callus tissue.

The corns and calluses we get on our feet form for exactly the same reason: increased skin pressure and stress in specific locations. The skin is again faced with its only two choices: build up or break down. Ironically, the buildup of skin intended to protect is is actually the source of our discomfort. Each step can be a painful reminder that our skin is doing a great job of growing. It will continue to grow faster in those areas that pressures remain highest, unless we do something about it. Before discussing treatment options, it is helpful to have a good working knowledge of some of the factors that cause the increase in pressure that results in corn and callus formation.