It is believed that an imbalance between new bone formation and old bone reabsorption causes osteoporosis. Women over the age of 50 are at greater risk than most people. Other risk factors* include:
- Family history of osteoporosis.
- Being small framed and thin.
- Menopause, especially before 45
- Low testosterone levels in men
- Low calcium and vitamin D intake, or an excessive intake of protein, sodium, and caffeine
- Inactive lifestyle
- Smoking and excessive alcohol intake
- Certain medications including steroid medications and seizure medication
- Certain diseases and conditions including anorexia nervosa, rheumatoid arthritis, and gastrointestinal diseases (such as malabsorption syndromes, and inflammatory disease)