American Medical Association Family Medical Guide - American Medical Association [695]
Preventing Osteoporosis
Because bone changes in response to environmental factors (such as what you eat and the amount of exercise you get), you can take steps to keep your bones strong. The following measures can help you avoid osteoporosis:
Calcium
Taking in a sufficient amount of calcium (see page 5) helps build and maintain bone strength throughout life. Good sources of calcium include low-fat or fat-free dairy products (such as skim milk), fish with edible bones (such as sardines), and green, leafy vegetables. Too many children get a substantial portion of their daily calories from fruit drinks, soft drinks, and high-fat, high-calorie snacks instead of from calcium-rich foods such as dairy products. Encourage your children to eat foods that are rich in calcium.
Vitamin D
Vitamin D helps the body absorb and use calcium. Oily fish such as salmon, vitamin D-fortified milk, and eggs are good sources of vitamin D. Although your body makes some vitamin D when you expose your skin to sunlight, you need to get most of your vitamin D from your diet or from supplements.
Weight-bearing exercise
Weight-bearing exercise such as walking, climbing stairs, and jogging stimulates new bone growth by putting stress on the bones. Lifting weights and doing exercises such as push-ups have the same effect. It’s never too late to start exercising. If you have been diagnosed with osteoporosis, your doctor will probably recommend low-impact exercises such as walking and ask you to avoid activities such as tennis and golf that involve twisting.
Medication
Most of the medications used to treat osteoporosis (see previous page) are also used to prevent it when taken before significant bone loss has occurred.
Osteogenesis Imperfecta
Osteogenesis imperfecta, sometimes called brittle bone disease, is a genetic disorder that causes bones to break easily, often for no apparent reason. The disorder results from a genetic defect that affects the body’s production of collagen, the major protein in connective tissue that provides structure and strength to the skeleton. A person with osteogenesis imperfecta has abnormal collagen or has less collagen than normal.
Osteogenesis imperfecta has four forms, which can vary greatly in severity from one person to another. Type I is the mildest, most common form; type II is usually fatal at or within a year of birth; type III is progressively deforming; and type IV is moderately severe. People with the same type of osteogenesis imperfecta, even members of the same family, can have different symptoms that differ in severity.
The genetic defect occurs in a dominant gene that is either inherited or is the result of a spontaneous mutation (change) in a parent’s egg or sperm cell before conception. For this reason, a person who has the disorder has a 50 percent chance of passing the gene (and therefore the disorder) on to each of his or her children. If you or a relative has osteogenesis imperfecta, talk to a genetic counselor (see page 952) to learn your risk of transmitting the disorder to a child.
Symptoms
The most obvious symptom of osteogenesis imperfecta is bones that break easily. Other symptoms of the most common form (type I) include loose joints and poor muscle tone; a blue, purple, or gray tint to the whites of the eyes; a triangular face; curvature of the spine; bone deformities; a gray tint to the teeth; or hearing loss beginning in the person’s 20s or 30s. The less common, more severe forms can cause bone deformities, short stature, a barrel-shaped rib cage, or respiratory problems. The most severe form (type II) can be fatal at or shortly after birth, often because the child is born with underdeveloped lungs.
Diagnosis and Treatment
Doctors can usually diagnose osteogenesis imperfecta from the symptoms. The diagnosis is sometimes confirmed by a chemical analysis of the person’s collagen or by a genetic test (see page 953). There is no cure for osteogenesis imperfecta. The goal of treatment is to prevent or control the symptoms and help the person achieve optimal bone and muscle