- Arts & Literature
- Science & Technology
By Jonathan Tomlin
Taller women are at greater risk from ovarian cancer, according to Oxford University researchers.
Every two inches in height was found to increase the chance of developing the disease by seven per cent.
The research, published in the journal PLoS Medicine, involved 47 studies, with over 100,000 women, including about 25,000 women with ovarian cancer.
Height has been linked to an increased risk of cancer for many years, but this was the most comprehensive study into ovarian cancer.
Professor Valerie Beral of the Epidemiology Unit, the lead researcher, told the BBC: “By bringing together worldwide evidence, it became clear that height is a risk factor.”
Scientists still do not know the cause of the link.
Dr Gillian Reeves of the Cancer Epidemiology Unit, who was also involved in the study, said: “The fact that height is clearly associated with risk may well be important for understanding how ovarian cancer develops.”
She added: “Although we do not yet know why height is related to ovarian cancer risk, there are a number of possible explanations.
“For example, the association that we see may be due to the biological effects of factors associated with height – such as increased levels of insulin like growth factor (IGF-1) (which has been associated with a number of other cancers such as breast and prostate cancer), or increase numbers of cells being at risk of becoming cancerous. Future studies should clarify this.”
Ovarian cancer is the fifth most common cancer in women, with over 6,500 cases diagnosed each year. Two-thirds of these cases are fatal because the disease is often symptomless before it spreads.
Age and not having children increase the chance of contracting the disease, while the contraceptive pill helps to protect against it spreading.
But obesity is still shown to be a greater factor in increasing women’s risk of developing the cancer.
Sarah Williams, health information officer at Cancer Research UK, said: “This study included as much evidence as possible to produce a clearer picture of the factors that can affect a woman’s risk of developing ovarian cancer, and found that body size was important.
“Women can reduce their risk of this and many other diseases by keeping to a healthy weight. For women trying to lose weight, the best method is to eat healthily, eat smaller amounts and be more physically active.”
Dr Paul Pharoah, a cancer researcher at Cambridge University, said that the increase in risk was small.
He said: “If we compare a woman who is 5ft tall with a woman who is 5ft 6in tall, there is a relative difference in ovarian cancer risk of 23%.
“But the absolute risk difference is small. The shorter woman will have a lifetime risk of about 16-in-a-1000 which increases to 20-in-a-1000 for the taller woman.
“A similar difference in absolute risk would be seen when comparing a slim woman with a body mass index of 20 to a slightly overweight woman with a body mass index of 30.”