London - The taller you are, the greater your risk of developing cancer, according to a study.
Scientists have calculated that lifetime cancer risk increases on average by about 18 percent in women and 11 percent in men for every 10cm increase in height.
The risk is even greater for some specific cancers. The risk of breast cancer in women increases by 20 percent for every 10cm increase in height, while malignant melanoma increases by about 30 percent for every 10cm height increase for both men and women, the study found.
It is not the first time that researchers have identified a link between adult height and risk of cancer, but it is probably the largest study to establish such a clear connection. The scientists analysed the medical records kept on 5.5 million Swedish men and women born between 1938 and 1991, including height records from the country's national passport register. The researchers followed the progress of each participant from the age of 20 until the end of 2011, which enabled them to establish the link between height and cancer.
The findings, which have not yet been published in a scientific journal but will be presented at a European endocrinology conference in Barcelona, were not influenced by socioeconomic differences such as education and income, said Emelie Benyi, a PhD student at the Karolinksa Institute in Stockholm.
“To our knowledge, this is the largest study performed on linkage between height and cancer including both women and men. It should be emphasised that our results reflect cancer incidence on a population level,” Ms Benyi said. “As the cause of cancer is multifactorial, it is difficult to predict what impact our results have at the individual level. Identifying different risk factors for cancer could be the first step in understanding the mechanisms behind cancer.”
Various explanations have been put forward for the results. These include greater exposure to growth hormone in childhood, greater number of cells in the body, a higher intake of calories or, in the case of malignant melanoma, greater surface area of skin.
“Our studies show that taller individuals are more likely to develop cancer but it is unclear so far if they also have a higher risk of dying from cancer,” Ms Benyi said.
Professor Mel Greaves, of the Institute of Cancer Research in London, said other factors such as family history and obesity have a greater impact than height.
The Independent