The risk of osteoporosis increases with age as bones naturally become thinner. After age 30, the rate at which your bone dissolves and is absorbed by the body slowly increases, while the rate of bone building decreases. Both men and women lose a small amount (approximately 0.4%) of bone each year after age 30.¹

In women, more rapid bone loss usually begins after monthly menstrual periods stop, when a woman's production of the hormone estrogen slows down (usually between the ages of 45 and 55). A man's bone thinning starts to develop gradually when production of the hormone testosterone slows down, at about 45 to 50 years of age. Women typically have smaller and lighter bones than men. As a result, women develop osteoporosis almost 4 times more often than men.² Osteoporosis usually does not have an effect on people until they are 60 or older.

Whether a person develops osteoporosis depends on the thickness of the bones (bone density) in early life, as well as health, diet, and physical activity later in life. Factors that increase the risk of osteoporosis in both men and women include:

• Having a family history of osteoporosis. If your mother, father, or a sibling has been diagnosed with osteoporosis or has experienced broken bones from a minor injury, you are more likely to develop osteoporosis.
• Lifestyle factors. These include:
  • Smoking. People who smoke lose bone thickness faster than nonsmokers.
  • Alcohol use. Heavy alcohol use can decrease bone growth and increase the risk of falling. However, moderate alcohol use (no more than 2 drinks a day for men and 1 drink a day for women) is linked to higher bone thickness. Most doctors recommend limiting, but not eliminating, alcohol use.⁵
  • Getting little or no exercise. Weight-bearing exercises-such as walking, jogging, stair climbing, dancing, or lifting weights-keep bones strong and healthy by working the muscles and bones against gravity. Exercise may improve your balance and decrease your risk of falling.
  • Being small-framed or thin. People with small frames are more likely to develop osteoporosis because they have smaller bones and less bone mass. Thin people are more likely to develop osteoporosis because they have less body fat. Fat cells make estrogen, which may protect women from bone loss after menopause. However, being overweight puts a woman at risk for other serious medical conditions, including type 2 diabetes, high blood pressure, and coronary artery disease (CAD).
  • A diet low in foods containing calcium, phosphorus, and vitamin D.
  • Drinking cola soft drinks. Cola, but not other carbonated soft drinks, may be linked to low bone mineral density in women.⁶
• Having certain medical conditions, such as hyperthyroidism or rheumatoid arthritis, that put you at greater risk for osteoporosis.
• Taking certain medications. Several medications cause bone thinning, such as:
  • Corticosteroids, used to treat conditions such as asthma and chronic obstructive pulmonary disease (COPD). If used for a period of 6 months or longer, corticosteroids can lead to steroid-induced osteoporosis.⁷
  • Medications used to treat endometriosis.
  • Aromatase inhibitors, used to treat breast cancer.
  • Thyroid replacement medication, if the dose is more than the body needs. This should be monitored by checking the level of thyroid stimulating hormone (TSH) every year.
  • Depo-Provera, a birth control medication given by injection. Longtime use may thin bones.
  • Antacids that contain aluminum, if they are overused. Aluminum-containing antacids remove phosphorus and calcium from your body.
  • Anticonvulsant medications such as carbamazepine.⁸
• Having certain surgeries, such as having your ovaries removed before menopause.