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.
Malnutrition can result in brittle fingernails that crack and split. Fingernails are composed of a strong protein called keratin that allows the nails to grow long without splitting or cracking.In order for keratin to produce strong nails, the body must be functioning properly.alnutrition can result in brittle fingernails that crack and split. Fingernails are composed of a strong protein called keratin that allows the nails to grow long without splitting or cracking.