Just adding a few pounds of extra weight can raise a person’s risk of developing 10 common cancers.
Researchers from the London School of Hygiene and Tropical Medicine gathered data on 5.2m people in the UK, of which nearly 170,000 developed cancer, and found that a person’s Body Mass Index, a measure of body fat, was linked to 17 out of 22 cancers.
The findings, published in the Lancet medical journal, suggest BMI was “positively associated” with 10 most common cancers, including uterus, cervix, thyroid, kidney, liver and colon. Post-menopausal breast cancer and leukaemia were also a heightened risk, the scientists said.
A person is deemed to be overweight if they have a BMI score, calculated using their weight and height, of 25 to 30 and are obese if it is above 30.
The study, funded by the National Institute for Health Research, Wellcome Trust and Medical Research Council, said that for every two stone women gained, their risk of womb cancer grew by 62%, the risk of cervical cancer rose by 10% and ovarian cancer by 9%.
For men, every two-and-a-half stone (or two stone for women) increased the risk of kidney or gall bladder cancer by 31% while liver cancer risks grew by 19%.
Dr Krishnan Bhaskaran, who led the study, said more than 12,000 cases of the 10 most common cancers could be attributed to obesity.
“The number of people who are overweight or obese is rapidly increasing worldwide,” he said.
“It is well recognised this is likely to cause more diabetes and cardiovascular disease. Our results show that if these trends continue, we can also expect to see substantially more cancers as a result.
“The higher the BMI, the higher the risk.”
It comes after a report by Nuffield Health in April revealed many people were unaware they were overweight or of the health risks it could lead to.
Research conducted by the charity found that two-fifths of obese people had no concerns about serious illness due to their weight.
Speaking at the time Dr Davina Deniszczyc, medical director for wellbeing at Nuffield Health, said: “We are seeing a vast number of people unwittingly straying into dangerous medical territory and perhaps not realising that the obesity awareness campaigns are directed at them.”
The researchers believe excess weight accounts for 41% of uterine and 10% of gall bladder, kidney, liver and colon cancers in Britain.