Most adults grew up being told to drink milk to help grow strong bones. But as we age, our bone mineral density, or bone mass, decreases naturally due to several factors. One of those factors is osteoporosis, a condition that develops when bone mineral density is low. When this happens, it can result in frequent fractures to your bones. More than 10% of adults over age 50 have osteoporosis, and nearly 45% of adults over age 50 have low bone mass, putting them at risk for the disease. But your bones are constantly rebuilding themselves, which means you can take steps to protect your bone density and prevent osteoporosis.

Although bones stop growing between the ages of 25 and 30, they are still constantly renewing themselves. As bones age, the old bone is reabsorbed into your body as new bone is formed, a process that takes around 10 years for each bone. As you get older, however, your bones break down faster than new bone grows. This leads to a decrease in bone mineral density – the amount of calcium and other minerals in your bone – starting in your 40s. And because your digestive system only absorbs less than 20% of the calcium in your diet, drinking a glass of milk at every meal like you might have done as a child won't do enough to keep your bones strong.

Some form of bone loss is inevitable, but some people are at a higher risk for low bone density and osteoporosis. They include women, white people, and Asian Americans, as well as those who:

• Consume large amounts of alcohol use
• Do not get enough physical activity
• Eat a poor diet
• Have a family history of osteoporosis
• Have a small or slim frame
• Have medical conditions, such as HIV, gastrointestinal disorders, and rheumatoid arthritis
• Smoke
• Take certain medications for acid reflux, asthma, depression, and seizures

In addition, drops in estrogen and testosterone, due to age or a hormonal disorder, can contribute to osteoporosis risk.

No matter your age, it's always a good time to take steps to protect your bone health, especially if you know you have one or more risk factors that increase your chance of developing osteoporosis later in life. Here's how to get started:

• Change your diet. Eat foods high in calcium and vitamin D, along with a well-balanced diet that provides all the nutrients you need, to help keep bones healthy.
• Cut back or quit drinking. Limit consumption to no more than one drink a day for women and two drinks a day for men.
• Exercise. Research shows that weight-bearing exercises, such as walking and running, along with strength training, such as weightlifting and resistance training, can help bone health. Doing exercises that can improve your balance, such as yoga, may also be helpful.
• Quit smoking. Tobacco has been linked to decreased bone density, although the exact connection remains unclear. Protect your bones – and the rest of your body – and kick the habit if you smoke.

Your provider may also recommend taking calcium, vitamin D, and other supplements to help in osteoporosis prevention. Women may benefit from hormone replacement therapy or taking medications called bisphosphonates that can slow bone loss.

Osteoporosis is often called a "silent" disease because for many people, the first sign they have it is when they break a bone. The U.S. Preventive Services Task Force recommends that women aged 65 and older have a bone mineral density (BMD) screening, which measures bone density. Post-menopausal women under 65 who are at high risk of the disease may also need one. At this time, scans are not suggested for all men, only those whose providers recommend them.

A BMD test is a low-dose X-ray called a DEXA or DXA scan that shows how thick your bones are. A central DXA scan measures the bone mass in your spine and hip, while a peripheral scan measures bone density in your hands and feet. Results can tell you if you have good bone health, low bone density, or osteoporosis.