When the body is deficient in B vitamins, the skin may appear dry, cracked, flaky and prone to infection. If the tests confirm that the body is indeed deficient in vitamin B, it can be supplemented through oral intake under the guidance of a doctor. However, it is important to note that not all itchy soles of the feet are vitamin deficient. There are also possible causes of diseases such as ringworm, sweat rash and palmoplantar keratosis, and it is not advisable to take vitamin supplements blindly.