Cracks in the skin around the heel are common and never look good and can become painful. The cracks, technically known as heel fissures, occur in the dry callused skin that can develop around the heel in many people. Once that skin cracks, it can not heal as it is dead skin and the crack or fissure can tear the good skin below it. If that happens it will be painful and can act as a portal for an infection to enter. For this reason you need to take cracked heels seriously.
As the skin become dry and hard it becomes vulnerable to the cracks. When we are standing or walking the fat pad under the heel expands out sideways and puts a lot of pressure on that vulnerable skin. That pressure from the underlying fat pad is what causes that skin to crack. Cracked heels are more common in those who are overweight and wear open back shoes. A closed in shoe helps reduce the stress on the vulnerable skin from the fat pad expanding out sideways. There is no vitamin deficiency that causes cracked heels.
How to deal with cracked heels?
To deal with cracked heels, you are going to need to put in a bit of work. The first step is to get rid of the callused hard skin. A podiatrist can do that by careful debridement. A simple foot file could also help and so can an electric callus remover. It probably does not matter how its done, but it needs to be done as there is no cracked heel cream that is going to remove all that hard and dry skin.
Once that skin has been removed, you are then going to have to regularly apply an emollient cream to the skin to keep it supple and flexible so that it is not vulnerable to the cracks. This really does need to be done every day. The urea based creams are good for this. If there is any callus or hard skin that starts to build up, then you are going to need to go back to the podiatrist, use the foot file or the electric callus remover.