Whether your doctor calls it osteopenia or low bone mass, consider it a warning. Bone loss has started, but you can still take action to keep your bones strong and maybe prevent osteoporosis later in life. That way you will be less likely to break a wrist, hip, or vertebrae (bone in your spine) when you are older.

Osteoporosis is a disease that weakens bones to the point where they break easily—most often, bones in the hip, backbone (spine), and wrist. Osteoporosis is called a “silent disease” because you may not notice any changes until a bone breaks. All the while, though, your bones had been losing strength for many years.

Bone is living tissue. To keep bones strong, your body breaks down old bone and replaces it with new bone tissue. Sometime around age 30, bone mass stops increasing, and the goal for bone health is to keep as much bone as possible for as long as you can. As people enter their 40s and 50s, more bone may be broken down than is replaced.

A close look at the inside of bone shows something like a honeycomb. When you have osteoporosis, the spaces in this honeycomb grow larger, and the bone that forms the honeycomb gets smaller. The outer shell of your bones also gets thinner. All of this makes your bones weaker.

Bone loss is the amount of minerals, such as calcium, that your body absorbs (takes) from your bones.

Bone loss can happen for several reasons. Some of the most common reasons include:

• You do not get enough calcium from food. Your body uses calcium to build healthy bones and teeth and stores calcium in your bones. Your body also uses calcium to send messages through your nervous system, help your muscles contract, and regulate your heart's rhythm. But your body does not make calcium. You have to get all the calcium your body needs from the foods you eat and drink (or from supplements). If you don't get enough calcium each day, your body will take the calcium it needs from your bones.
• You are past menopause. As you get older, your bones don't make new bone fast enough to keep up with your body's needs. The calcium taken from your bones causes you to lose bone density. Bone loss also speeds up after menopause and can lead to weak, brittle bones.

For some people, the first sign of osteoporosis is to realize they are getting shorter or to break a bone easily. Don’t wait until that happens to see if you have osteoporosis. You can have a bone density test to find out how strong your bones are.

The U.S. Preventive Services Task Force recommends that women aged 65 and older be screened (tested) for osteoporosis, as well as women under age 65 who are at increased risk for an osteoporosis-related fracture.

A bone mineral density test compares your bone density to the bones of an average healthy young adult. The test result, known as a T-score, tells you how strong your bones are, whether you have osteoporosis or osteopenia, and your risk for having a fracture.

Strong bones support us and allow us to move. They protect our heart, lungs, and brain from injury. Our bones are also a storehouse for vital minerals we need to live. Weak bones break easily, causing terrible pain. You might lose your ability to stand or walk. And as bones weaken, you might lose height.

Silently and without warning, bones may begin to weaken early in life if you do not have a healthy diet and the right kinds of physical activity. Many people already have weak bones and don’t know it. Others are making choices that will weaken their bones later.

Weak bones cause the spine to collapse.

There are several kinds of bone disease. The most common is osteoporosis. In this disease, bones lose minerals like calcium. They become fragile and break easily. With osteoporosis, your body’s frame becomes like the frame of a house damaged by termites. Termites weaken your house like osteoporosis weakens your bones. If you have severe fractures from osteoporosis, you risk never walking again. Weak bones can break easily. This can be fatal.

Fragile bones are not painful at first. Unfortunately, most people don’t realize they have weakened bones until one breaks. By that time, it is hard to make your bones strong again.

Osteoporosis causes weak bones.

The good news is that you are never too old or too young to improve your bone health. There are many things you can do to keep bones strong and prevent fractures. At all ages, a diet with enough calcium and vitamin D, together with weight-bearing physical activity every day, can prevent problems later. You can work with your doctor to check out warning signs or risk factors. When you are older, you can have your bones tested and take medicine to strengthen them.

Why does bone health matter?

Our bones support us and allow us to move. They protect our brain, heart, and other organs from injury. Our bones also store minerals such as calcium and phosphorous, which help keep our bones strong, and release them into the body when we need them for other uses.

There are many things we can do to keep our bones healthy and strong. Eating foods rich in calcium and vitamin D, getting plenty of exercise, and having good health habits help keep our bones healthy.

But if we don’t eat right and don’t get enough of the right kinds of exercise, our bones can become weak and even break. Broken bones (called fractures) can be painful and sometimes need surgery to heal. They can also cause long-lasting health problems.

But the good news is that it is never too late to take care of your bones.

What is osteoporosis?

There are many kinds of bone diseases. The most common one is osteoporosis (AH-stee-oh-por-OH-sis). With osteoporosis, our bones become weak and are more likely to break. People with osteoporosis most often break bones in the wrist, spine, and hip.

Our bones are alive. Every day, our body breaks down old bone and puts new bone in its place. As we get older, our bones break down more bone than they put back. It is normal to lose some bone as we age. But, if we do not take steps to keep our bones healthy, we can lose too much bone and get osteoporosis.

Many people have weak bones and don’t even know it. That’s because bone loss often happens over a long period of time and doesn’t hurt. For many people, a broken bone is the first sign that they have osteoporosis.

Who gets osteoporosis?

There are many things that can increase your chances of getting osteoporosis. These things are called “risk factors.” Some risk factors are things you can control, and some things are outside of your control.

Risk factors you can control:

• Diet. Getting too little calcium can increase your chances of getting osteoporosis. Not getting enough vitamin D can also increase your risk for the disease. Vitamin D is important because it helps the body use the calcium in your diet.
• Physical activity. Not exercising and not being active for long periods of time can increase your chances of getting osteoporosis. Like muscles, bones become stronger – and stay stronger – with regular exercise.
• Body weight. Being too thin makes you more likely to get osteoporosis.
• Smoking. Smoking cigarettes can keep your body from using the calcium in your diet. Also, women who smoke go through menopause earlier than those who don’t smoke. These things can increase your risk for osteoporosis.
• Alcohol. People who drink a lot are more likely to get osteoporosis.
• Medicines. Certain medicines can cause bone loss. These include a type of medicine called glucocorticoids (gloo-ko-KOR-ti-koids). Glucocortiocoids are given to people who have arthritis, asthma, and many other diseases. Some other medicines that prevent seizures and that treat endometriosis (en-do-me-tree-O-sis), a disease of the uterus, and cancer can cause bone loss, too.

Risk factors you cannot control:

• Age. Your chances of getting osteoporosis increase as you get older.
• Gender. You have a greater chance of getting osteoporosis if you are a woman. Women have smaller bones than men and lose bone faster than men do because of hormone changes that happen after menopause.
• Ethnicity. White women and Asian women are most likely to get osteoporosis. Hispanic women and African American women are also at risk, but less so.
• Family history. Having a close family member who has osteoporosis or has broken a bone may also increase your risk.

Am I really at risk?

Because more women get osteoporosis than men, many men think they are not at risk for the disease. Many Hispanic and African American women are not concerned about their bones either. They believe that osteoporosis is only a problem for white women. However, it is a real risk for older men and women from all backgrounds.

Also, people from certain ethnic backgrounds may be more likely to have other health problems that increase their risk for bone loss. If you have one of the following health problems, talk to your doctor about your bone health:

How do I know if I have osteoporosis?

Since osteoporosis does not have any symptoms until a bone breaks, it is important to talk to your doctor about your bone health. If your doctor feels that you are at risk for osteoporosis, he or she may order a bone density test. A bone density test measures how strong – or dense – your bones are and whether you have osteoporosis. It can also tell you what your chances are of breaking a bone. Bone density tests are quick, safe, and painless.

What can I do to make my bones healthier?

It is never too early or too late to take care of your bones. The following steps can help you improve your bone health:

• Eat a well-balanced diet rich in calcium and vitamin D. Good sources of calcium include low-fat dairy products, and foods and drinks with added calcium. Good sources of vitamin D include egg yolks, saltwater fish, liver, and milk with vitamin D. Some people may need to take nutritional supplements in order to get enough calcium and vitamin D. The charts below show how much calcium and vitamin D you need each day. Fruits and vegetables also contribute other nutrients that are important for bone health.

Recommended calcium and vitamin D intakes

Definitions: mg = milligrams; IU = International Units
Source: Food and Nutrition Board, Institute of Medicine, National Academy of Sciences, 2010.

• Get plenty of physical activity. Like muscles, bones become stronger with exercise. The best exercises for healthy bones are strength-building and weight-bearing, like walking, climbing stairs, lifting weights, and dancing. Try to get 30 minutes of exercise each day.
• Live a healthy lifestyle. Don’t smoke, and, if you choose to drink alcohol, don’t drink too much.
• Talk to your doctor about your bone health. Go over your risk factors with your doctor and ask if you should get a bone density test. If you need it, your doctor can order medicine to help prevent bone loss and reduce your chances of breaking a bone.
• Prevent falls. Falling down can cause a bone to break, especially in someone with osteoporosis. But most falls can be prevented. Check your home for dangers like loose rugs and poor lighting. Have your vision checked regularly. Increase your balance and strength by walking every day and taking classes like Tai Chi, yoga, or dancing.

Will I need to take medicine for my bones?

There are medicines to help prevent and treat osteoporosis. These include bisphosphonates; estrogen agonists/antagonists (also called selective estrogen receptor modulators or SERMs); calcitonin; parathyroid hormone; estrogen therapy; hormone therapy; and a recently approved RANK ligand (RANKL) inhibitor. Your doctor may want you to take medicine if your bone density test shows that your bones are weak and that you have a good chance of breaking a bone in the future. Your doctor is more likely to order medicine if you have other health concerns that increase your risk for breaking a bone, such as a tendency to fall or a low body weight.

Like muscle, bone is living tissue that responds to exercise by becoming stronger. Young women and men who exercise regularly generally have greater bone mass (bone density and strength) than those who do not. For most people, bone mass peaks by the late twenties. After the age of 30, women and men can help prevent bone loss with regular exercise. The best activities for bones are weight-bearing and resistance exercises. Weight-bearing exercises force you to work against gravity. They include walking, hiking, jogging, climbing stairs, playing tennis, and dancing. Resistance exercises – such as lifting weights – can also strengthen bones. Swimming and bicycling are examples of non-weight-bearing exercises.

Although weight-bearing and resistance activities contribute to the development and maintenance of bone mass, weightlessness and immobility can result in bone loss. Space travel has provided significant research data on the subject of weightlessness and bone loss. Astronauts exposed to the microgravity of space experience significant bone loss, leaving their bones weak and less able to support the body’s weight and movement upon return to Earth.

The impact of bed rest and inactivity

Some people can’t perform weight-bearing activity. They include, for example, people who are on prolonged bed rest because of surgery, serious illness, or complications of pregnancy; and those who are experiencing immobilization of some part of the body because of stroke, fracture, spinal cord injury, or other chronic conditions. These people often experience a significant bone loss and are at high risk for developing osteoporosis and having a fracture.

Bone loss typically occurs over several months and then gradually levels off as the bones adjust to the state of weightlessness.

Maintaining bone health

In general, healthy people who undergo prolonged periods of bed rest or immobilization can regain bone mass when they resume weight-bearing activities. Studies suggest that there is a good chance to fully recover the lost bone if the immobilization period is limited to 1 to 2 months. Additionally, even brief intervals of weight-bearing activity during periods of limited mobility or bed rest can help lessen bone loss.

The greatest concern is for people who cannot resume weight-bearing activities and therefore typically do not regain lost bone density. Studies suggest that taking an osteoporosis treatment medication and reducing or eliminating other risk factors for osteoporosis can help slow the rate of bone loss.

The bottom line

• A lifetime of weight-bearing exercise is important for building and maintaining bone mass, improving balance and coordination, and promoting overall good health.
• Weight-bearing exercise should be resumed and maintained after a prolonged period of bed rest or immobilization to help recover bone lost during disuse.
• Those who cannot resume weight-bearing exercise are at significant risk for osteoporosis. In this case, it is important to reduce or eliminate other risk factors for osteoporosis, such as smoking and excessive alcohol consumption, and to eat a diet rich in calcium and vitamin D. Taking an osteoporosis medication may also be an option to minimize bone loss.

Bones feel solid, but the inside of a bone is actually filled with holes like a honeycomb. Bone tissues are broken down and rebuilt all the time. While some cells build new bone tissue, others dissolve bone and release the minerals inside.

As we get older, we begin to lose more bone than we build. The tiny holes within bones get bigger, and the solid outer layer becomes thinner. In other words, our bones get less dense. Hard bones turn spongy, and spongy bones turn spongier. If this loss of bone density goes too far, it’s called osteoporosis. Over 10 million people nationwide are estimated to have osteoporosis.

It’s normal for bones to break in bad accidents. But if your bones are dense enough, they should be able to stand up to most falls. Bones weakened by osteoporosis, though, are more likely to break.

“It’s just like any other engineering material,” says Dr. Joan McGowan, an NIH expert on osteoporosis. If you fall and slam your weight onto a fragile bone, “it reaches a point where the structures aren’t adequate to support the weight you’re putting on them.” If the bone breaks, it’s a major hint that an older person has osteoporosis.

Broken bones can lead to serious problems for seniors. The hip is a common site for osteoporosis, and hip fractures can lead to a downward spiral of disability and loss of independence. Osteoporosis is also common in the wrist and the spine.

The hormone estrogen helps to make and rebuild bones. A woman’s estrogen levels drop after menopause, and bone loss speeds up. That’s why osteoporosis is most common among older women. But men get osteoporosis, too.

“A third of all hip fractures occur in men, yet the problem of osteoporosis in men is frequently downplayed or ignored,” says Dr. Eric Orwoll, a physician-researcher who studies osteoporosis at Oregon Health and Science University. Men tend to do worse than women after a hip fracture, Orwoll says.

Experts suggest that women start getting screened for osteoporosis at age 65. Women younger than age 65 who are at high risk for fractures should also be screened. Men should discuss screening recommendations with their health care providers.

Screening is done with a bone mineral density test at the hip and spine. The most common test is known as DXA, for dual-energy X-ray absorptiometry. It’s painless, like having an X-ray. Your results are often reported as a T-score, which compares your bone density to that of a healthy young woman. A T-score of −2.5 or lower indicates osteoporosis.

There’s a lot you can do to lower your risk of osteoporosis. Getting plenty of calcium, vitamin D, and exercise is a good start, Orwoll says.

Calcium is a mineral that helps bones stay strong. It can come from the foods you eat—including milk and milk products, dark green leafy vegetables like kale and collard greens—or from dietary supplements. Women over age 50 need 1,200 mg of calcium a day. Men need 1,000 mg a day from ages 51 to 70 and 1,200 mg a day after that.

Vitamin D helps your body absorb calcium. As you grow older, your body needs more vitamin D, which is made by your skin when you’re in the sun. You can also get vitamin D from dietary supplements and from certain foods, such as milk, eggs, fatty fish, and fortified cereals. Talk with your health care provider to make sure you’re getting a healthy amount of vitamin D. Problems can arise if you’re getting too little or too much.

Exercise, especially weight-bearing exercise, helps bones, too. Weight-bearing exercises include jogging, walking, tennis, and dancing. The pull of muscles is a reminder to the cells in your bones that they need to keep the tissue dense.

Smoking, in contrast, weakens bones. Heavy drinking does too—and makes people more likely to fall. Certain drugs may also increase the risk of osteoporosis. Having family members with osteoporosis can raise your risk for the condition as well.

The good news is, even if you already have osteoporosis, it’s not too late to start taking care of your bones. Since your bones are rebuilding themselves all the time, you can help push the balance toward more bone growth by giving them exercise, calcium, and vitamin D.

Several medications can also help fight bone loss. The most widely used are bisphosphonates. These drugs are generally prescribed to people diagnosed with osteoporosis after a DXA test, or to those who’ve had a fracture that suggests their bones are too weak. Bisphosphonates have been tested more thoroughly in women, but are approved for men too.

Researchers are trying to develop drugs that increase bone growth. For now, there’s only one available: parathyroid hormone. It’s effective at building bone and is approved for women and men with osteoporosis who are at high risk for having a fracture.

Another important way to avoid broken bones is to prevent falling and occasions for fracture in the first place. Unfortunately, more than 2 million so-called fragility fractures (which wouldn’t have happened if the bones had been stronger) occur nationwide each year. “To reduce the societal burden of fracture, it’s going to take a combined approach of not only focusing on the skeleton but focusing on fall prevention,” says Dr. Kristine Ensrud, a physician-researcher who studies aging-related disorders at the University of Minnesota and Minneapolis VA Health Care System.

Many things can affect the risk for a fall, such as how good a person’s balance is and how many trip hazards are in the environment. The kind of fall matters, too. Wrist fractures often occur when a person falls forward or backward. “It’s the active older person who trips and puts her hand out,” McGowan says. Hip fractures often arise when a person falls to the side. Your hip may be strong enough to handle weight that goes up and down, but not an impact from another direction.

“That’s why exercise that builds balance and confidence is very good at preventing fractures,” McGowan says. For example, she says, tai chi won’t provide the loads needed to build bone mass, but it can increase balance and coordination—and make you more likely to catch yourself before you topple.

NIH-funded researchers are looking for better ways to tell how strong your bones are, and how high your chances are of breaking a bone. For now, though, the DXA test is the best measure, and many seniors, even older women, don’t get it, Ensrud says. If you’re concerned about your bone health, she adds, “Ask your health care provider about the possibility of a bone density test.”

Prevent Falls To Protect Bones

To prevent falls at home:

• Keep rooms free of clutter, especially on floors.
• Don’t walk in socks, stockings, or slippers.
• Be sure rugs have skid-proof backs or are tacked to the floor.
• Keep a flashlight next to your bed to guide you in the dark.

Exercises to improve balance:

• Stand on one leg at a time for a minute. Slowly increase the time. Try to balance with your eyes closed or without holding on.
• Stand on your toes for a count of 10, and then rock back on your heels for a count of 10.
• Move your hips in a big circle to the left, and then to the right. Do not move your shoulders or feet. Repeat 5 times.