Brittle bones danger
Around the world, every three seconds a bone fractures owing to osteoporosis. And one in three women and one in five men aged over 50 will suffer an osteoporosis-related fracture, according to the International Osteoporosis Foundation.
In the UK, more than three million people now have osteoporosis, with more than a quarter of a million fractures each year, and treating it is estimated to cost the NHS up to £2 billion a year.
‘The effects of osteoporosis are a major public health and social problem,’ says Professor Alan Silman, expert in musculoskeletal problems and medical director of Arthritis Research UK.
‘The trauma that causes fractures in older people with osteoporosis can be quite mild – falling out of bed, tripping over, and so on,’ he says. ‘From a public health viewpoint, we need to look at preventing, diagnosing and treating osteoporosis, but as a society we need to prevent falls.’ This can be done by ensuring that stairs are well lit and have handrails, fitting grab bars in bathrooms and placing non-slip mats in showers and the like.
‘We also need a follow-up system,’ Professor Silman adds, ‘so that when someone over 60 presents at A&E with a fractured wrist, that person will be tested for osteoporosis. It is important we take action as, with an ageing population, the numbers of people affected by it will grow.’
Bone weakness in late age
As we get older, our bones aren’t able to regenerate as well as they did when we were young, when bone is at its strongest. In young people the body makes new bone faster than it breaks down the old, so bone density increases, peaking at around the age of 30. After that, more bone is lost than gained.
This happens to almost everyone, but it becomes osteoporosis only when the bones become fragile and vulnerable to fractures. Often, it is diagnosed only after a fracture has occurred, usually to wrists, hips or vertebrae.
Bone is in a constant cycle of renewal, where specialised cells called osteoclasts break down the old bone and osteoblasts build new bone. But with advancing age, this remove-and-replace cycle can get out of balance, leading to increased bone loss and a drop in bone density.
Just why this happens is not clear, but there are a number of theories. For women, after the menopause there is a drop in levels of oestrogen, the female hormone essential for bone health, leading to a rapid decline in bone density. That’s why more women than men suffer from osteoporosis.
In most cases, it is not known why men develop osteoporosis, although with advancing age, there is a decline in levels of testosterone, which helps to keep bone healthy. The andropause (so-called male menopause) – a collection of symptoms that some men experience in their late forties/early fifties – has also been implicated.
A wide range of treatments can be prescribed for osteoporosis and, while effective, some carry a risk of side effects. Hormone replacement therapy (HRT) was once widely used for women, but it has been linked to a risk of stroke and breast cancer and, according to the NHS, is almost never used to treat osteoporosis these days.
Weight-bearing exercise, such as brisk walking, and an active lifestyle are known to strengthen and maintain healthy bones. However, there is growing interest in alternative, non-pharmaceutical treatments and research is increasingly showing that many dietary changes may have beneficial effects. But the emphasis is still on that word ‘may’.
What women should eat to protect against osteoporosis
An onion a day may keep osteoporosis at bay. Onions can improve bone density and lower the risk of a hip fracture, according to researchers at the Medical University of South Carolina, who compared the bones of women aged over 50, who ate onions daily, to those who ate them less than once a month.
Regular eaters were found to have 5% greater bone density. Older women who ate onions daily were calculated to be 20% less likely to have a hip fracture. A compound in onions called GPCS is thought to slow the removal of old tissue, making bones denser and stronger. Silicon content in onions may also help in the process of turning calcium into bone.
Prunes are the most effective fruit for preventing as well as reversing bone loss, according to a study at Florida State University that involved 236 postmenopausal women.
Bone density was measured at the start and the end of the year-long trial, during which half the women ate 100g (3½oz) prunes a day and the others ate 100g dried apple. Prunes significantly increased bone density of the spine, so something in prunes seems to improve bone turnover, the researchers concluded.
A high intake of fish increases bone density and lowers osteoporosis risk, according to a study of nearly 700 postmenopausal Chinese women. Those who ate the most had a 75% lower risk of osteoporosis than those who ate the least. They also had up to 7% higher bone density and up to 9% greater bone mineral content.
‘Higher intake of sea fish is independently associated with greater bone mass and lower osteoporosis risk,’ say the researchers.
A glass of beer may boost bone health in women. Researchers at the University of Extremadura, Spain, used ultrasound to measure bone density and then compared the results against diet, including beer and wine. Beer drinkers were found to have better bone health; compounds in beer called phytoestrogens, which mimic some of the actions of the hormone oestrogen, may be responsible.
The hormone that may be good for your bones:
High levels of the so-called cuddle hormone, oxytocin – which increases in the blood after cuddling or kissing – may be good for the bones. Researchers at the University of Nice found that postmenopausal women with severe osteoporosis had low blood levels of the hormone. Just how oxytocin works is not clear, but one theory is that it stimulates the osteoblasts responsible for bone formation.
What men should eat to protect against osteoporosis
Men who ate plenty of fruit and vegetables had up to a 39% lower risk of hip fractures, according to a study at the National University of Singapore. Antioxidant compounds called carotenoids, found at high levels in carrots, and which give fruit and veg their colour, are likely to be responsible. The study was based on more than 63,000 men and women aged 45 to 74, who were monitored for a decade.
Men who drank the most tea had a 48% lower risk of a hip fracture than those who drank the least, according to a study at Sun Yat-sen University in China. One theory is that tea is a major source of antioxidants called flavonoids, which may play a role in maintaining bone density. One tea flavonoid – epigallocatechin-3-gallate – has been shown to improve bone density.
Olive oil in the diet increases levels of a compound called osteocalcin, which has a protective effect on bones, according to a two-year study on men aged 55 to 80 at Madrid University. This may help to explain why osteoporosis rates are lower in southern Europe where traditional diets have high intakes of olive oil.
Conventional medical treatments for osteoporosis for men and women
Calcium and Vitamin D supplements can reduce the risk of hip fracture in older people according to an NHS report, which says that in order to have the right effect, relatively high doses are needed – over the counter preparations may not contain enough calcium. There is a slight risk of heart attack when taking a calcium supplement, so don’t self-medicate – consult your doctor first.
These work by reducing the action of osteoclasts, the cells that break down old bone, slowing down the rate of bone loss. Studies have found they produce significant increases in bone density in women. Prescribed as a tablet or injection. Possible side effects include irritation to the oesophagus, nausea and stomach pain.
This also works by slowing down bone loss and by boosting the growth of new bone. It is taken as a powder dissolved in water. Possible side effects include nausea and diarrhoea.
Conventional medical treatments for osteoporosis for women
Selective oestrogen receptor modulators (SERMS)
These have a similar effect to oestrogen, and help to maintain bone density and reduce the risk of fracture. Available as tablets. Possible side effects include hot flushes, fatigue and a potential increased risk of blood clots.
Conventional medical treatments for osteoporosis for men
Useful for men whose osteoporosis is linked to poor production of the male sex hormone, testosterone.
Find out more
Contact the National Osteoporosis Society at www.nos.org.uk