Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly throughout your life. During childhood and your teens, your body adds new bone faster than it removes old bone. After about age 20, you can lose bone faster than you make bone. To have strong bones when you are young, and to prevent bone loss when you are older, you need to get enough calcium, vitamin D, and exercise. You should also avoid smoking and drinking too much alcohol.

Bone diseases can make bones easy to break. Different kinds of bone problems include

• Low bone density and osteoporosis, which make your bones weak and more likely to break
• Osteogenesis imperfecta makes your bones brittle
• Paget's disease of bone makes them weak
• Bones can also develop cancer and infections
• Other bone diseases, which are caused by poor nutrition, genetics, or problems with the rate of bone growth or rebuilding

Osteoporosis is a bone disease that develops when bone mineral density and bone mass decreases, or when the quality or structure of bone changes. This can lead to a decrease in bone strength that can increase the risk of fractures (broken bones).

Osteoporosis is a “silent” disease because you typically do not have symptoms, and you may not even know you have the disease until you break a bone. Osteoporosis is the major cause of fractures in postmenopausal women and in older men. Fractures can occur in any bone but happen most often in bones of the hip, vertebrae in the spine, and wrist.

However, you can take steps to help prevent the disease and fractures by:

• Staying physically active by participating in weight-bearing exercises such as walking.
• Drinking alcohol in moderation.
• Quitting smoking, or not starting if you don’t smoke.
• Taking your medications, if prescribed, which can help prevent fractures in people who have osteoporosis.
• Eating a nutritious diet rich in calcium and vitamin D to help maintain good bone health.

Osteogenesis imperfecta (OI) is a genetic disorder in which bones break easily. Sometimes the bones break for no known reason. OI can also cause weak muscles, brittle teeth, a curved spine, and hearing loss. OI is caused by one of several genes that aren't working properly. When these genes don't work, it affects how you make collagen, a protein that helps make bones strong.

OI can range from mild to severe, and symptoms vary from person to person. A person may have just a few or as many as several hundred fractures in a lifetime.

No single test can identify OI. Your doctor uses your medical and family history, physical exam, and imaging and lab tests to diagnose it. Your doctor may also test your collagen (from skin) or genes (from blood). There is no cure, but you can manage symptoms. Treatments include exercise, pain medicine, physical therapy, wheelchairs, braces, and surgery.

Paget’s disease of bone is a chronic (long-lasting) disorder that causes bones to grow larger and become weaker than normal. The disease usually affects just one or a few bones. The bones most commonly affected by Paget’s disease include:

• Pelvis.
• Skull.
• Spine.
• Femur and tibia (leg bones).

Many people with Paget’s disease do not experience symptoms specific to the disease. However, the bone changes can cause:

• Bone pain.
• Misshapen bones.
• Broken bones (fractures).
• Inflammation and arthritis in the joints close to the affected bones.

With treatment, many people can manage their symptoms, improve pain, and control the effects of the disease.

What Happens in Paget’s Disease?

Throughout your lifetime, the body constantly removes old bone and adds new bone to the skeleton. As we age, it is normal for this process to happen at a slower pace. As the disease starts, the body loses much more bone than it makes. As Paget’s disease progresses, new bone forms at a faster rate than the rate at which old bone is removed. However, the new bone does not form correctly, leading to larger bones that are misshapen, weaker, and softer than normal bone.

Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another part of the body is more common.

There are three types of bone cancer:

• Osteosarcoma - occurs most often between ages 10 and 19. It is more common in the knee and upper arm.
• Chondrosarcoma - starts in cartilage, usually after age 40
• Ewing's sarcoma - occurs most often in children and teens under 19. It is more common in boys than girls.

The most common symptom of bone cancer is pain. Other symptoms vary, depending on the location and size of the cancer. Surgery is often the main treatment for bone cancer. Other treatments may include amputation, chemotherapy, and radiation therapy. Because bone cancer can come back after treatment, regular follow-up visits are important.

Like other parts of the body, bones can get infected. The infections are usually bacterial, but can also be fungal. They may spread to the bone from nearby skin or muscles, or from another part of the body through the bloodstream. People who are at risk for bone infections include those with diabetes, poor circulation, or recent injury to the bone. You may also be at risk if you are having hemodialysis.

Symptoms of bone infections include

• Pain in the infected area
• Chills and fever
• Swelling, warmth, and redness

A blood test or imaging test such as an x-ray can tell if you have a bone infection. Treatment includes antibiotics and often surgery.

Osteoporosis and tooth loss are health concerns that affect many older men and women. Osteoporosis is a condition in which the bones become less dense and more likely to fracture. This disease can affect any bone in the body, although the bones in the hip, spine, and wrist are affected most often. In the United States more than 53 million people either already have osteoporosis or are at high risk due to low bone mass.

Research suggests a link between osteoporosis and bone loss in the jaw. The bone in the jaw supports and anchors the teeth. When the jawbone becomes less dense, tooth loss can occur, a common occurrence in older adults.

Skeletal bone density and dental concerns

The portion of the jawbone that supports our teeth is known as the alveolar process. Several studies have found a link between the loss of alveolar bone and an increase in loose teeth (tooth mobility) and tooth loss. Women with osteoporosis are three times more likely to experience tooth loss than those who do not have the disease.

Low bone density in the jaw can result in other dental problems as well. For example, older women with osteoporosis may be more likely to have difficulty with loose or ill-fitting dentures and may have less optimal outcomes from oral surgical procedures.

Periodontal disease and bone health

Periodontitis is a chronic infection that affects the gums and the bones that support the teeth. Bacteria and the body’s own immune system break down the bone and connective tissue that hold teeth in place. Teeth may eventually become loose, fall out, or have to be removed.

Although tooth loss is a well-documented consequence of periodontitis, the relationship between periodontitis and skeletal bone density is less clear. Some studies have found a strong and direct relationship among bone loss, periodontitis, and tooth loss. It is possible that the loss of alveolar bone mineral density leaves bone more susceptible to periodontal bacteria, increasing the risk for periodontitis and tooth loss.

Role of the dentist and dental x-rays

Research supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) suggests that dental x-rays may have benefits as a screening tool for osteoporosis. Researchers found that dental x-rays were highly effective in distinguishing people with osteoporosis from those with normal bone density.

Because many people see their dentist more regularly than they see their doctor, dentists are in a unique position to help identify people with low bone density and to encourage them to talk to their doctors about their bone health. Dental concerns that may indicate low bone density include loose teeth, gums detaching from the teeth or receding gums, and ill-fitting or loose dentures.

Effects of osteoporosis treatments on oral health

It is not known whether osteoporosis treatments have the same beneficial effect on oral health as they do on other bones in the skeleton. Additional research is needed to fully clarify the relationship between osteoporosis and oral bone loss; however, scientists are hopeful that efforts to optimize skeletal bone density will have a favorable impact on dental health.

Bisphosphonates, a group of medications available for the treatment of osteoporosis, have been linked to the development of osteonecrosis of the jaw (ONJ), which is cause for concern. The risk of ONJ has been greatest in patients receiving large doses of intravenous bisphosphonates, a therapy used to treat cancer. The occurrence of ONJ is rare in individuals taking oral forms of the medication for osteoporosis treatment.

Taking steps for healthy bones

A healthy lifestyle can be critically important for keeping bones strong. You can take many important steps to optimize your bone health:

• Eat a well-balanced diet rich in calcium and vitamin D.
• Engage in regular physical activity or exercise. Weight-bearing activities – such as walking, jogging, and dancing – are the best for keeping bones strong. Resistance exercises, such as lifting weights, also can strengthen bones.
• Don’t smoke, and limit alcohol intake.
• Report any problems with loose teeth, detached or receding gums, and loose or ill-fitting dentures to your dentist and your doctor.

Osteomalacia is a disease that is characterized by a weakening of the bone, often due to a deficiency of vitamin D. This vitamin supports the development of the bones of the body, so when there are low levels of vitamin D, the bones are not strong enough. Symptoms of osteomalacia can include muscle weakness, bone pain, and walking with a waddling gait. Pain is especially likely to occur in the lower back, hips, and legs. The weakening of the bones may also cause them to easily fracture.

Osetomalacia can be caused by having a low level of vitamin D in the diet or lack of sun exposure. The condition may also be the result of an underlying disease such as celiac disease, or kidney or liver disorders.

Diagnosis of osteomalacia is possible through blood or urine tests to check for vitamin D levels or a bone biopsy. Treatment options include supplementing the diet with more vitamin D or calcium. Any underlying condition will also need to be treated.

The bones of the human body are made up of living cells that need a blood supply to stay healthy. In osteonecrosis, blood flow to part of a bone is disrupted. This results in death of bone tissue, and the bone can eventually break down and the joint will collapse. Osteonecrosis is also called:

• Avascular necrosis.
• Aseptic necrosis.
• Ischemic necrosis of bone.

Osteonecrosis can happen to any bone, but most often it develops in the ends of long bones, such as the:

• Thigh bone (femur), especially the upper part—the ball in the hip socket. The lower end, which is part of the knee joint, is also often affected.
• Upper arm bone (humerus), especially the upper part—the ball in the shoulder joint.

When the disease involves part of a bone in a joint, it can lead to the breakdown of the bone and arthritis.

Less often, the bones of the elbows, ankles, feet, wrists and hands are affected.

The primary symptom of osteonecrosis is pain, and doctors usually diagnose the disease using imaging methods such as x-rays or magnetic resonance imaging (MRI). Most people require surgical treatment to prevent further bone damage, to protect the bones and joints, and to improve use of the joints.

Osteopetrosis refers to a group of rare, inherited skeletal disorders characterized by increased bone density and abnormal bone growth. Symptoms and severity can vary greatly, ranging from neonatal onset with life-threatening complications (such as bone marrow failure) to the incidental finding of osteopetrosis on X-ray. Depending on severity and age of onset, features may include fractures, short stature, compressive neuropathies (pressure on the nerves), hypocalcemia with attendant tetanic seizures, and life-threatening pancytopenia. In rare cases, there may be neurological impairment or involvement of other body systems.Osteopetrosis may be caused by mutations in at least 10 genes. Inheritance can be autosomal recessive, autosomal dominant, or X-linked recessive with the most severe forms being autosomal recessive. Management depends on the specific symptoms and severity and may include vitamin D supplements, various medications, and/or surgery. Adult osteopetrosis requires no treatment by itself, but complications may require intervention.

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.