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.
Facts and Figures
Osteoporosis is a major public health threat
for 44 million Americans, 68 percent of whom are women.
In the U.S. today,
10 million individuals already have osteoporosis and 34 million more have low
bone mass, placing them at increased risk for this disease.
One out of every
two women and one in four men over 50 will have an osteoporosis-related fracture
in their lifetime.
More than 2 million American men suffer from
osteoporosis, and millions more are at risk. Each year, 80,000 men have a hip
fracture and one-third of these men die within a year.
strike at any age.
Osteoporosis is responsible for more than 1.5 million
fractures annually, including 300,000 hip fractures, approximately 700,000
vertebral fractures, 250,000 wrist fractures, and more than 300,000 fractures at
Based on figures from hospitals and nursing homes, the
estimated national direct expenditures for osteoporosis and related fractures
total $14 billion each year.
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
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.
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
– Your chances of developing osteoporosis are greater if you are
a woman. Women have less bone tissue and lose bone faster than men because of
the changes that happen with menopause.
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
Ethnicity – Caucasian and
Asian women are at highest risk. African American and Hispanic women have a
lower but significant risk.
history – Fracture risk may be due, in part, to heredity. People
whose parents have a history of fractures also seem to have reduced bone mass
and may be at risk for fractures.
Risk factors you can
Sex hormones – Abnormal
absence of menstrual periods (amenorrhea), low estrogen level (menopause), and
low testosterone level in men can bring on osteoporosis.
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
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.
intake – Excessive consumption increases the risk of bone loss
To reach optimal peak bone mass and continue
building new bone tissue as you age, there are several factors you should
Calcium: An inadequate supply of calcium over a
lifetime contributes to the development of osteoporosis. Many published studies
show that low calcium intake appears to be associated with low bone mass, rapid
bone loss, and high fracture rates. National nutrition surveys show that many
people consume less than half the amount of calcium recommended to build and
maintain healthy bones. Good sources of calcium include low-fat dairy products,
such as milk, yogurt, cheese, and ice cream; dark green, leafy vegetables, such
as broccoli, collard greens, bok choy, and spinach; sardines and salmon with
bones; tofu; almonds; and foods fortified with calcium, such as orange juice,
cereals, and breads. Depending upon how much calcium you get each day from food,
you may need to take a calcium supplement.
Calcium needs change during one’s lifetime.
The body’s demand for calcium is greater during childhood and adolescence, when
the skeleton is growing rapidly, and during pregnancy and breastfeeding.
Postmenopausal women and older men also need to consume more calcium. Also, as
you age, your body becomes less efficient at absorbing calcium and other
nutrients. Older adults also are more likely to have chronic medical problems
and to use medications that may impair calcium absorption.
Calcium Intakes (mg/day)