Your body forms new bone at a faster pace than it loses it (resorption) until around age 30. After age 30, bone loss slowly gets faster than bone formation.

Something as harmless as coughing can cause a rib to break, but the most common cause of broken bones is a fall. The most common places for a bone to break are the back, wrist, and hip. It's important to prevent falls. Here are ideas:

• Use glasses or a hearing aid, if needed.
• Ask your healthcare provider if any of the medicines you are taking may make you dizzy or unsteady on your feet.
• Use a cane or walker if your walking is unsteady.
• Wear rubber-soled and low-heeled shoes.
• Make sure all the rugs and carpeting in your house are firmly attached to the floor.
• Keep your rooms well lit and the floor free of clutter.
• Use nightlights.

White and Asian women have the highest risk. African-American and Latino women have a lower risk.

After age 30, men and women slowly begin to lose bone. In women, the rate of loss increases for several years after menopause. It then slows again, but continues. In men, the bone loss occurs more slowly. But by age 65 or 70, men and women are losing bone at the same rate. Men have only a fourth as many hip fractures as women. But men over age 75 are 3 times more likely to die after a hip fracture than are women.

Drinking too much alcohol interferes with how your body uses calcium and vitamin D. Both of these nutrients are important for healthy bones. Men with alcoholism also tend to make less testosterone. This is a hormone that helps with bone formation. Women with alcoholism can have irregular menstrual cycles. This lowers the amount of the hormone estrogen, which is important for bone health. Family history is another risk factor. If your parents have a history of broken bones, you may also be at risk for them. Smokers may have less bone density. But researchers aren’t sure if that’s because of smoking or because of other lifestyle factors like poor diet or too little exercise. Smoking causes a woman’s body to make less estrogen. Men who smoke are 2 to 3 times more likely to get osteoporosis.

Ordinary X-rays don’t show bone loss until a large amount of bone density is gone. The best way to find bone density is by getting a DEXA scan (dual-energy X-ray absorptiometry). This is a painless, low-dose X-ray. Common places for the scan are the spine, hip, wrist, middle finger, heel, and shinbone. The DEXA scan can show whether you are at risk for a broken bone. If you have already broken a bone and your doctor thinks you might have osteoporosis, the test can confirm the diagnosis.

A broken vertebra in the spine is called a compression fracture. The compression shortens the person's height. This causes a curved back.

Weight-bearing exercise is the only kind of exercise that builds bone density. Try walking, playing tennis, jogging, or dancing 3 times a week.

Follow a diet that has plenty of calcium and vitamin D and get regular weight-bearing exercise. These are the best ways to prevent weakened bones later in later life. People ages 31 to 50 should get 1,000 mg of calcium each day. People over 50 should get 1,200 mg daily. Your body uses vitamin D to absorb calcium. Being out in the sun for 10 to 15 minutes a day, without sunscreen, 2 days a week helps most people’s bodies make enough vitamin D. You can also get vitamin D from eggs, fatty fish, and cereal and milk fortified with vitamin D, as well as from supplements. Exercise makes bones and muscles stronger and helps prevent bone loss. It also helps you stay active and mobile. Weight-bearing exercises done 3 to 4 times a week are best. Good choices are walking, jogging, playing tennis, and dancing.

Treatment of osteoporosis aims to stop bone loss and rebuild bone. Making lifestyle changes can help. Several medicines are also available. Some will slow how fast you lose bone. Others will actually rebuild bone. These include estrogen, raloxifene, alendronate, risedronate, denosumab, and calcitonin. Doctors sometimes prescribe estrogen to replace the hormones lost during menopause. This slows the rate of bone loss and increases bone mass in the spine and hip. But estrogen and progesterone treatment may raise the risk for other health conditions.