More than 300 Irish cancer deaths a year are caused by overweight and obesity, a study has found.
While the public is aware of the risks of excess body weight for heart disease and diabetes, it is also a major risk factor for cancer, according to researchers in the HSE and the National Cancer Control Programme.
The study estimates that 4.5 per cent of newly diagnosed invasive cancers can be attributed to excess body weight, or a yearly average of 784 cases and 310 deaths.
This estimate is likely to be conservative, because of the variation in relative risks identified in the scientific literature, the authors say.
Pancreatic cancer was not included in the analysis for technical reasons, although the most recent international studies also indicate a link here with high body fat
The risk varies for different sites in the body. The greatest number of cancers attributable to excess weight are colorectal cancers in men and post-menopausal breast cancer in women.
Colorectal cancer
Under 8 per cent of breast cancer cases are weight-related, equating to 153 cases a year. For men this factor underlies 212 cases of colorectal cancer annually.
The highest rates of deaths causally related to excess body weight – defined as a body-mass index of over 25 – was seen for endometrial cancer (33 per cent, or 20 cases annually) and oesophageal adenocarcinoma (32 per cent, or 16 cases).
Pancreatic cancer was not included in the analysis for technical reasons, although the most recent international studies also indicate a link here with high body fat.
The study, published in the latest edition of the Irish Medical Journal, says a clear and concerted information campaign is needed for healthcare professionals and the public to highlight the risks of excess body weight in relation to cancer. Further initiatives to counteract the "obesogenic environment" and to facilitate necessary behavioural change are also needed.