1 A diet low in calcium and vitamin D makes you more prone to bone loss. 2  Medication use. 3  Some medicines increase the risk of osteoporosis. 4  Activity level. 5  Lack of exercise or long-term bed rest can cause weak bones. 6  Smoking. 7  Cigarettes are bad for bones, and the heart, and lungs, too. 8  Drinking alcohol.
When Toes Turn Dark. Nails change colors for multiple reasons. The most common culprit for a black toenail is blood under the hard tissue. Damage to the end of the toe causes blood to leak through the nail bed and stain the keratin a dark color. This is also known as a subungual hematoma, or a bruise under the nail.
Symptoms of Toenail Trauma. A subungual hematoma can range from a small spot under the nail to a large area of discoloration. Depending on the amount of blood beneath the nail, the nail may come loose. But often the nail does stay intact, and the blood fades as the nail grows out.