There are many causes of dry and cracked heels, which may be related to vitamin deficiency. When the body is deficient in vitamin A, it is more likely to experience generalised dryness, but it is more likely to occur on the lateral femur, the back of the upper arm, the neck, shoulders and buttocks, which is reflected in the feet as dry and cracked heels, but the feet are not among the most common sites.
If you are tested for vitamin A deficiency, you should ensure a full nutritional intake and take vitamin A supplements if necessary under medical supervision.