Osteoporosis is literally translated at "porous bone" and is a disease characterized by low bone mass and deterioration of bone tissue, leading to enhanced bone fragility and a consequent increase in fracture risk. Bone mass can be measured and, according to the Women's Health Organization (WHO) study group, four diagnostic criteria have been established in women.

Normal: a value for bone mass within 1 SD of the young adult reference mean. Low bone mass (osteopenia): a value for bone mass more than 1 SD below the young adult mean but less than 2.5 SD below this value.

Osteoporosis: a value for bone mass 2.5 SD or more below the young adult mean. Severe osteoporosis: a value for bone mass 2.5 SD or more below the young adult mean in the presence of one or more fragility fractures. Usually bone mass is expressed as T-score, with a T-score=0 as the young adult reference mean.


Although osteoporosis is also a disease of men, this classification is only available for women. Maintaining bone strength is an important component of overall health. Bones provide the structural support your body needs in order to function properly. And bone health becomes increasingly important as you grow older and hormonal changes begin to affect your skeleton. Bones are made up of living tissue (mainly collagen) that is constantly remodeling. This process, also called bone turnover, consists of two major phases: bone resorbtion — when bone collagen is broken down, and bone formation — when bone is rebuilt. In healthy adult bone, these phases are balanced. During menopause, estrogen levels go down. At the same time, bone breakdown (resorption) may increase. When levels of bone resorption are higher than levels of bone formation, overall bone loss may occur. Because of this, menopause is the number one risk factor for developing osteoporosis. Indeed, most bone loss occurs within five to seven years after menopause. Cigarette smoking accelerates the onset of menopause and increases the risk for osteoporosis. HRT relieves menopausal symptoms and helps prevent osteoporosis. Seventy-five percent of women ages 45 to 75 have never talked with a doctor about osteoporosis, according to a Gallup poll.


Osteoporosis risk factors:

• Being female
• Being postmenopausal
• A small, thin frame
• Advanced age
• Family history of osteoporosis
• Early menopause
• Diet low in calcium
• Use of certain medications (steroids, anticonvulsants, excessive thyroid hormones, certain cancer treatments)
• Sedentary lifestyle
• Cigarette smoking
• Excessive alcohol intake

Please see the "Osteoporosis Ask the Expert Archives" for more information.