New research has confirmed tall people have a greater risk of cancer because they possess more cells in their body.
The research specified average height for women as 162cm (5 feet, 4 inches) for women and 175cm (5 feet, 9 inches) for men. It revealed a person’s risk of developing cancer increases by 10% for every 4 inches.
Other research has also linked height to health problems like heart problems, diabetes, and blood clots among others.
Leonard Nunney, a professor of biology at the University of California Riverside tested the analyzed previous sets of data on people who had contracted cancer — each of which included more than 10,000 cases for both men and women — and compared the figures with anticipated rates based on their height.
He tested the hypothesis that this was connected to the number of cells against alternatives and found it held in 18 of the 23 cancers tested, the study says.
The research also found that the increase in risk is greater for women, with taller women 12% more likely to contract cancer and taller men 9% more likely to do so. Those findings matched with Nunney’s predicted rates, using his models, of 13% for women and 11% for men.
Colon and kidney cancer and lymphoma were among the types of cancer for which the correlation was strongest.
‘We’ve known that there is a link between cancer risk and height for quite a long time — the taller someone is, the higher the cancer risk,’ Georgina Hill from Cancer Research UK said.
‘What we haven’t been sure of is why — whether this is simply because a taller person has more cells in their body, or whether there’s an indirect link, such as something to do with nutrition and childhood,’ added Hill, who was not involved in the study.
She said the study provides good evidence of the ‘direct effect’ theory that the total number of cells does indeed cause the link.
She, however, said lifestyle still poses a higher risk than height in developing cancer.
‘It was only a slightly higher risk and that there are more important actions that people can take to make positive changes, [such as] stopping smoking and maintaining a healthy weight,’ she said.
Two of the types of cancer tested for, thyroid cancer and melanoma, were found to be more susceptible to an increase in risk than expected, and Nunney suggested in the study that other factors could be at play in those cases, such as geography.
‘There are no obvious reasons for these exceptions, although the author speculates that cell turnover rates may come into play for melanoma,’ Dorothy C. Bennett, director of the Molecular and Clinical Sciences Research Institute in London said.