Osteoporosis, or porous bone, is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to bone fragility and an increased risk of fractures of the hip, spine, and wrist. Men as well as women are affected by osteoporosis, a disease that can be prevented and treated.

What Is Bone?
Bone is living, growing tissue. It is made mostly of collagen, a protein that provides a soft framework, and calcium phosphate, a mineral that adds strength and hardens the framework.

This combination of collagen and calcium makes bone both flexible and strong, which in turn helps it to withstand stress. More than 99 percent of the body’s calcium is contained in the bones and teeth. The remaining 1 percent is found in the blood.
Throughout your lifetime, old bone is removed (resorption) and new bone is added to the skeleton (formation). During childhood and teenage years, new bone is added faster than old bone is removed. As a result, bones become larger, heavier, and denser. Bone formation outpaces resorption until peak bone mass (maximum bone density and strength) is reached around age 30. After that time, bone resorption slowly begins to exceed bone formation.
For women, bone loss is fastest in the first few years after menopause, and it continues into the postmenopausal years. Osteoporosis – which mainly affects women but may also affect men – will develop when bone resorption occurs too quickly or when replacement occurs too slowly. Osteoporosis is more likely to develop if you did not reach optimal peak bone mass during your bone-building years.

Risk Factors
Certain risk factors are linked to the development of osteoporosis and contribute to an individual’s likelihood of developing the disease. Many people with osteoporosis have several risk factors, but others who develop the disease have no known risk factors. There are some you cannot change and others you can.

Risk factors you cannot change:
    -Gender – Your chances of developing osteoporosis are greater if you are a woman.
    -Age – The older you are, the greater your risk of osteoporosis. Your bones become thinner and weaker as you age.
    -Body size – Small, thin-boned women are at greater risk.
    -Ethnicity – Caucasian and Asian women are at highest risk. African American and Hispanic women have a lower risk
    -Family history – Fracture risk may be due, in part, to heredity.

Risk factors you can change:
    -Sex hormones – Abnormal absence of menstrual periods (amenorrhea), low estrogen level (menopause), and low testosterone
    -Anorexia nervosa – Characterized by an irrational fear of weight gain, this eating disorder increases your risk for osteoporosis.
    -Calcium and vitamin D intake – A lifetime diet low in calcium and vitamin D makes you more prone to bone loss.
    -Medication use – Long-term use of glucocorticoids and some anticonvulsants can lead to loss of bone density and fractures.
    -Lifestyle – An inactive lifestyle or extended bed rest tends to weaken bones.
    -Cigarette smoking – Cigarettes are bad for bones as well as the heart and lungs.
    -Alcohol intake – Excessive consumption increases the risk of bone loss and fractures.

Symptoms
Osteoporosis is often called the “silent disease” because bone loss occurs without symptoms. People may not know that they have osteoporosis until their bones become so weak that a sudden strain, bump, or fall causes a hip to fracture or a vertebra to collapse. Collapsed vertebrae may initially be felt or seen in the form of severe back pain, loss of height, or spinal deformities such as kyphosis (severely stooped posture).