Why do I, or any other human, get sore and cracked heels? I understand it’s less common in men than women – presumably this is down to footwear choices? The cream product I use to cure it works very well, but its active ingredient appears to be urea. How does this react with my skin to cure the problem?
• The commonest reasons for sore and cracked heels are a failure to remove a build up of keratin around the heels or an infection.
Pressure from footwear and excessive weight can cause a dense layer that stresses the underlying tissue. Extra physical effort, other than normal showering, is needed to remove it. Rubbing any emollient into the skin helps, but those containing urea help specifically by drawing water into the keratin.
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Opportunistic fungal skin infections, such as tinea pedis, can contribute to the severity of the problem, and should be suspected if the cracks do not respond to heel creams.
Celia Drakard, Registered podiatrist, Woodbridge, Suffolk, UK
• Cracked heels can start with calluses brought on by friction caused by ill-fitting shoes. If this skin dries or has a fungal infection, it loses its elasticity and is prone to cracking. This can be exacerbated by ageing, weight, psoriasis and diabetes.
Urea can penetrate the skin’s outermost layer. Here it readily absorbs and retains water, promoting rehydration of the skin. At concentrations of 40 per cent, urea causes the layer to loosen and exfoliate, diminishing the likelihood of cracking. Also, by improving the hydration of the skin, urea makes it more permeable to topical drugs, enhancing treatment of infections and inflammation.
David Muir, Edinburgh, UK
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