Osteoporosis literally means 'porous bones'.
The bones in our skeleton are made of a thick outer shell and a
strong inner mesh filled with collagen (protein), calcium salts
and other minerals. The inside looks like honeycomb, with blood
vessels and bone marrow in the spaces between bone. Osteoporosis
occurs when the holes between bone become bigger, making it
fragile and liable to break easily. Osteoporosis usually affects
the whole skeleton but it most commonly causes breaks
(fractures) to bone in the wrist, spine and hip.
Bone is alive and constantly changing. Old, worn out bone is
broken down by cells called osteoclasts and replaced by bone
building cells, called osteoblasts. This process of renewal is
called bone turnover.
In childhood the cells that make new bone work faster, enabling
the skeleton to increase in density and strength. During this
period of rapid bone growth it takes the skeleton just two years
to completely renew itself; in adults this takes seven to ten
years. Bones stop growing in length between the ages of 16-18
but continue to grow in strength into your mid-twenties. By this
age your bones have reached their maximum potential strength
(peak bone mass). Up until the age of 35 a balance between bone
breakdown and new bone formation means that bone density stays
stable. After this age, bone loss increases as part of the
natural ageing process. This can lead to osteoporosis and an
increased risk of fracture, particularly in women, due to
accelerated bone loss at the menopause.
Who is at risk?
We are all potentially at risk of osteoporosis because of the
bone loss that occurs as we get older, particularly as we are
living longer as a population. There are also many other factors
which can increase your risk:
-- A lack of
oestrogen, caused by early menopause (before the age of 45).
-- early hysterectomy (before the age of 45), especially if both
ovaries are removed (oophorectomy).
-- missing periods for six months or more (excluding pregnancy)
as a result of over-exercising or over-dieting.
-- low levels of the male hormone, testosterone (hypogonadism).
Men and Women
use of corticosteroid tablets (for conditions such as asthma,
-- maternal history of a hip fracture
-- malabsorption, inflammatory bowel
disease (Crohn's disease or ulcerative colitis) and gastric
-- long-term immobility
-- heavy drinking
-- low body weight.
If you have already broken a bone after a
minor bump or fall, you may already have osteoporosis. Other
warning signs include height loss and kyphosis (curvature of the
spine). If you also have a poor diet that is low in calcium and
you take little weight-bearing exercise you may also be at risk
of having osteoporosis. The good news is that osteoporosis can
be treated in most cases and there are many ways to help to
prevent osteoporosis and keep bones healthy.
How do I know if I have osteoporosis?
Because you cannot see or feel your bones getting thinner you
will probably be quite unaware of any problems with your bone
health. Osteoporosis is a silent disease and for most people,
the first sign that something is wrong can be when they break a
bone, often in the wrist or spine, after a minor bump or fall.
Osteoporosis should not be confused with osteoarthritis,
commonly called 'rheumatism'. They are different things.
Wrist fractures are particularly common in women in their
fifties but sadly osteoporosis frequently goes undiagnosed. In
the spine, osteoporosis can cause the small vertebrae to crush
or wedge, often causing chronic pain. However, some people may
not experience pain, and the first indication of osteoporosis
might be the resulting loss of height. If several bones crush
and form wedge shaped fractures the spine can start to curve.
Severe curvature of the spine can reduce the space under the rib
cage, cause digestive and breathing problems and sometimes
incontinence, as the internal organs are pressed on the bladder.
Hip fractures are most common in older people, usually after a
fall, and can have a big impact on quality of life.
Can I be tested for osteoporosis?
A simple X-ray of bone can highlight a
fracture but osteoporosis only shows on an X-ray when at least
30% of your bone density has been lost.
A bone density scan, called a Dual Energy X-ray
Absorptiometry (DEXA) scan, is used to measure the density
of bones. This test is currently the most accurate and reliable
means of assessing the strength of your bones and your risk of
fracture. It is a simple, painless procedure that uses very low
doses of radiation. You will be asked to lie down on the machine
for 10-15 minutes whilst an X-ray arm passes over you to take an
image of your spine and hip. Some centres have forearm machines
which measure the density of the wrist. A bone density scan can
diagnose osteoporosis, assess risk of fracture and monitor
effects of treatment.
How can I get a
bone density scan?
Bone density scans are only recommended for
people who are at high risk of osteoporosis, so discuss your
medical history with your doctor, who can decide whether to
refer you to a hospital for a scan. Your doctor may use the
results to decide on treatment for you, or you may be asked to
see a specialist consultant.
What will the
results tell me?
The results will show how your bone density
compares to the average bone density of both a young adult of
the same sex and someone the same age (and sex) as yourself. The
results can be given as a percentage of the normal value, or as
standard deviation, which means the number of units above or
below the average for the population. If your bone density is
between the normal range and the range defined as osteoporosis,
this is called osteopenia, which means you have low bone
What is a bone-friendly diet?
Healthy bones need a well-balanced diet, incorporating minerals
and vitamins from four different food groups, including bread
and cereals; fruit and vegetables; milk and dairy products;
meat, fish, eggs, pulses, nuts and seeds. You especially need to
ensure that your diet is rich in calcium. Calcium is the most
abundant mineral found in our bones and helps to give them
strength and rigidity. Men and women need different amounts of
calcium at different stages of life.
Good sources of calcium are milk and dairy
products such as cheese and yogurt. Don't worry if you are
watching your weight or cholesterol as low-fat varieties contain
just as much calcium as their full-fat counterparts. If you
don't like or are unable to eat dairy products, you should be
able to get enough calcium from non-dairy sources but it might
take a bit more planning. Non-dairy foods such as bread, green
leafy vegetables and baked beans all contain calcium. Be careful
not to have too much animal protein, salt or caffeine because in
excessive quantities these can reduce your body's ability to
absorb or retain calcium.
Vitamin D is needed to help the body absorb
calcium. Although foods such as dairy produce, margarine and
fish oils contain vitamin D, the major source of this vitamin is
from the action of sunlight on skin. About 15-20 minutes of
sunlight a day on the face and arms during the summer months is
adequate to enable the body to store enough vitamin D to last
the rest of the year. Be careful not to stay out in the sun too
long to avoid burning or increasing your risk of developing skin
cancer. Elderly people living in nursing homes who rarely get
outside may become deficient in vitamin D; supplements of
calcium and vitamin D may then be needed.
How to get enough calcium?
Milk, cheese and yogurt are good sources of
calcium because they are readily available, and contain high
amounts of calcium. There are also other foods which contain
high levels of calcium, such as bony fish or tofu and useful
amounts are found in vegetables like broccoli and spinach, dried
fruits such as figs or apricots and nuts and seeds. For children
who are reluctant to eat dairy products, calcium can also be
obtained from foods like baked beans, pizza or ice-cream. Adding
a cheese topping or a cheese or yoghurt sauce to meals can also
help to boost daily calcium intake. Most people should be able
to get enough calcium from their diet, but for people who find
this difficult, calcium supplements are an alternative. Calcium
and vitamin D supplements in the elderly have been shown to
reduce bone loss and fractures.
For people who have been diagnosed with osteoporosis, there are
a range of treatments available to help prevent bone loss:
replacement therapy (HRT), is a common means of
preventing and treating osteoporosis in women. Taking HRT also
helps to greatly relieve distressing menopausal symptoms such as
hot flushes, night sweats, headaches and vaginal dryness. Some
women may experience side effects such as breast tenderness and
temporary nausea but these symptoms usually stop after the first
few months or with a change of the type or dose of HRT. There
are over 30 forms of HRT available in pills, patches, implants
or gels. HRT does not prevent heart disease. If it is taken for
not longer than 2 years, it does not appreciably increase your
risk of developing breast cancer.
are non-hormonal drugs for osteoporosis which work by "switching
off" the cells that break down bone, allowing the bone building
cells to work more efficiently. There is solid evidence that
bisphosphonates like alendronate (Fosamax) and risedronate (Actonel)
are effective in reducing loss of bone mass and reducing the
risk of fracture. Fosamax is also licensed for the treatment of
osteoporosis caused by corticosteroids and for the prevention of
osteoporosis in women who have low bone mass (osteopenia).
3 Calcium and vitamin D supplements
are an effective treatment to reduce bone loss in the
elderly. Most people should be able to obtain adequate calcium
in their diet but supplements are an alternative for people who
find this difficult. Calcium alone has a limited effect as a
treatment for osteoporosis but combined with vitamin D, it is
particularly helpful for the elderly and housebound who cannot
obtain natural sunlight and may have a poor diet.
4 Calcitonin is a hormone
made by the thyroid gland which prevents the cells that break
down bone from working properly, improving the action of bone
building cells. Currently, calcitonin is available as an
injection and as a nose apray. Because calcitonin has a pain
killing effect it can be useful to use for a short time
following a spinal fracture.
5 Testosterone is a
treatment for men who are deficient in the male sex hormone, but
it can also increase bone density in men with osteoporosis who
have normal testosterone levels. It is available as injections
6 Anabolic steroids can
increase bone and muscle mass and may be helpful in the very
elderly who are frail and also in people with spinal fractures.
Nandralone decanoate is the only anabolic steroid currently
licensed for treating osteoporosis, and injections are carefully
monitored due to side effects.
7 SERMs (Selective
Estrogen Receptor Modulators) are a new generation of
drugs which reduce the risk of osteoporosis and heart disease,
but do not increase the risk of breast or endometrial cancers.
One form, raloxifene (Evista), is licensed for the prevention
and treatment of osteoporosis in post-menopausal women.