1 Calcium and vitamin D intake. 2  A diet low in calcium and vitamin D makes you more prone to bone loss. 3  Medication use. 4  Some medicines increase the risk of osteoporosis. 5  Activity level. 6  Lack of exercise or long-term bed rest can cause weak bones. 7  Smoking.
Signs and Symptoms. 1  Nail splitting affects the fingernails and the toenails. The condition may appear as a single horizontal split between layers of the nail plate at the growing end or as multiple splits and loosening of the growing edge of the nail plate.
Insufficient Vitamins and Minerals. Just as a lack of protein can cause your nails to split and crack, so too can insufficient vitamins and minerals. Many people claim that it is almost impossible to get insufficient vitamins, minerals and proteins in our diets but that just isnt true.