BBC News Online health staff
An eating disorder in her teens left Dr Anna Richman with a legacy of ill-health.
Anna still suffers from side effects
Aged only 32, Anna has osteoporosis - a condition usually associated with menopausal women twice her age.
Formerly a statuesque six footer Anna, used to be taller than her sisters, but the osteoporosis has taken at least two inches from her height.
"The irony is that I wanted to lose weight to have a better-shaped body.
"When I lost the height from my spine my waist actually disappeared and I was left with a protruding stomach.
"I will never get that height back. It seems to have gone from the top half of my body and it affects the way I dress."
As well as osteoporosis, anorexia can have further drastic effects on the body.
A lack of food deprives the body of protein and prevents the normal metabolism of fat.
The effects of this can include an irregular heart beat caused by a change in the heart muscle - which in turn can lead to heart failure and death.
Other problems can include ceasing of menstruation, dehydration, kidney stones and kidney failure.
Some anorexics also develop a fine, downy body hair, called lanugo, on the face and arms and their muscles waste away. Some suffer constipation or bowel irritation.
Anna, who now works as a hospital doctor in Liverpool, started to diet in her late teens.
"I was only dieting for 18 months, but the implications have gone on for years," he said.
It wasn't long after Anna started dieting that her weight got out of control.
Very soon she was hospitalised with anorexia.
"It did just start off as a bit of a diet. I lost a bit of weight and then it went from a diet to anorexia."
When Anna was first hospitalised her weight had plummeted to just seven-and-a-half stone.
Doctors helped her build her weight back up to over 10 stone.
But then she relapsed and needed hospitalisation as it slumped again to just six stone.
Watching her friends leave her behind as they gained their A' Levels and then university places, Anna struggled to take charge of her life again.
She took her exams and started to study medicine, but the damage had been done.
"When I was 19 I was just getting over the anorexia and had taken a part-time job in a nursing home.
One in three woman and one in 12 men over 50 have osteoporosis
Treating broken bones due to osteoporosis costs the NHS about £5 million a day
"I had a backache and was just told that everyone at the home used to get these.
"But then one day I was in excruciating pain with my back and I just fell to the floor. I could not walk and had to crawl back to bed."
Eventually doctors diagnosed Anna with osteoporosis and spotted that she had two compression fractures in the spine.
Her bone density was low and doctors recommended a high-dose pill to boost her levels.
But she found taking calcium tablets and doing weight bearing exercises worked better.
Emma Burrows, of the National Osteoporosis Society, said young women like Anna are at an increased risk of osteoporosis.
"Oestrogen is essential for healthy bones in women. Over-dieting can cause a drop in oestrogen levels similar to that experienced at the menopause and can result in fragile bones that are liable to break easily.
"It is essential that we all protect our bones by eating a healthy, well-balanced and calcium rich diet, and that doesn't mean it has to be fattening.
"Low-fat dairy products, such as skimmed milk, actually contain more calcium than the full-fat varieties, and calcium can come from non-dairy sources too.
"Young women who miss their periods for six months or more as a result of over-dieting or over-exercising are at an increased risk of suffering a broken bone due to osteoporosis and should talk to their GP about a possible bone scan or treatment."