Tall people have a higher risk of developing cancer - WalesOnline

BEING tall could increase the risk of developing 10 different types of cancer, startling research reveals today.

A study by experts at Oxford University has found that every 10cm (4in) increase in height also raises the relative risk of developing certain forms of cancer by as much as 16% in women.

It is not clear why taller people have a higher risk of cancer – further studies are needed to understand the link.

But it has been suggested that the link is due to hormone levels related to childhood growth and in turn to cancer risk in later life.

Some have also put forward the idea the link could be due to the fact taller people have more cells in their bodies and so a greater chance of developing cancerous cell changes.

The research, published today in The Lancet, found a link between height and 15 types of cancer by studying more than a million middle-aged women in the UK, involved in the Million Women Study.

The women ranged between 1.55m and 1.75m and taller. The average height for women in the UK today is 1.6m (5ft 4in).

Height was a "statistically significant" factor in 10 types of cancer – cancer of the colon, rectum, breast, lining of the womb, ovary, kidney, central nervous system, non-Hodgkin lymphoma, leukaemia and malignant melanoma.

No cancer showed height decreased risk of the disease.

Jane Green, the lead author of the study based at the Cancer Epidemiology Unit, at the University of Oxford, said: "We showed that the link between greater height and increased total cancer risk is similar across many different populations from Asia, Australasia, Europe and North America.

"The fact that the link between height and cancer risk seems to be common to many different types of cancer in different people, suggests there may be a basic common mechanism, perhaps acting early in peoples' lives, when they are growing.

"Of course people cannot change their height. And being taller has actually been linked to a lower risk of other conditions, such as heart disease."

The height of European adults increased by about 1cm (0.39 inches) per decade during the 20th century.

The study suggests this may explain around 10% to 15% of the rise in cancer cases seen over this period.

Sara Hiom, director of health information at Cancer Research UK, which part-funded the study, said: "Tall people need not be alarmed by these results.

"Most people are not a lot taller (or shorter) than average, and their height will only have a small effect on their individual cancer risk.

"This study confirms the link between height and cancer paving the way for studies to help us understand why this is so.

"On average, people in the UK have a more than one-in-three chance of developing cancer in their lifetime.

"So it's important that everyone is aware of what is normal for their body and go see their doctor as quickly as possible if they notice any unusual changes.

"And while we can't control our height, there are many lifestyle choices people can make that we know have a greater impact on reducing the risk of cancer, such as not smoking, moderating alcohol, keeping a healthy weight and being physically active."

Dr Caitlin Palframan, policy manager at Breakthrough Breast Cancer, said: "We already know being tall slightly increases the risk of developing cancer, and this study provides confirmation.

"The big question is why this connection exists. If we can unravel why height affects the risk of cancer, it will lead us closer to understanding how some cancers develop," she added.

Dr Ian Lewis, head of research at Welsh cancer charity Tenovus, said: "While height may provide new insights into what causes cancer further down the line, our natural height is predetermined and cannot be massively influenced by our actions.

"We can, however, have an impact on our predisposition to cancer through our health and by our lifestyle choices.

"Half of all cases of cancer can be prevented by making healthier lifestyle choices," he added.

"The single biggest risk factor for cancer, as well as a myriad of other diseases, is smoking.

"Smoking is Wales' biggest cancer killer, which can affect all people regardless of their genetic make-up."