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For certain cancers, escalating obesity is a higher risk to health than smoking

A new campaign from Cancer Research UK (CRUK) has been launched to highlight the danger of obesity and its link to cancer, revealing that being overweight is the leading cause of cancer of the bowel, kidneys, ovaries and liver. Figures published by the charity show that there are twice as many obese adults as smokers. “Our children could be a smoke-free generation, but we’ve hit a devastating record high for childhood obesity,” warns Michelle Mitchell, CRUK’s chief executive.

By comparing obesity and smoking in relation to cancer, CRUK hopes to educate the public and get the Government to take action. London-based nutrition and dietetic consultant, Linia Patel, explains, “The campaign by CRUK wanted to highlight the issue that the majority of the population (75%) are not aware of the correlation between obesity and cancer, and are much more aware of the impact of smoking. The reality is that obesity is on the rise, so while raising the issue of weight is such a sensitive topic, there is a need to create awareness (without fat shaming).

“It’s also important to remember that the causes of cancer are multifactorial, so the emphasis should be in creating healthy dietary and lifestyle changes that will, in turn, have a positive impact on weight,” she adds.

CRUK points out that scientists have so far identified that obesity causes 13 types of cancer. Extra body fat sends out signals that can tell cells to divide more often and, similar to smoking, can cause damage that builds up over time and raises the risk of cancer<1>.

The charity wants the Government to act on its ambition to halve childhood obesity rates by 2030 and introduce a 9pm watershed for junk food adverts on TV and online, alongside other measures such as restricting promotional offers on unhealthy food and drinks. In addition, CRUK points out that being active plays a vital role in the prevention of cancer as it helps regulate hormonal activity. CRUK explains that, when it comes to bowel cancer, exercise has a preventative role, as being active helps move food through our bodies. This reduces the amount of time any harmful chemicals in food waste are in contact with our bowel, helping to prevent cancer. “Further research is needed to find out more about the ways extra body fat can lead to cancer,” suggests Mitchell.

Professor Linda Bauld, Cancer Research UK’s prevention expert, explains that it’s time to follow smoking’s lead, “There isn’t a silver bullet to reduce obesity, but the huge fall in smoking over the years – partly thanks to advertising and environmental bans – shows that Government-led change works. It was needed to tackle sky-high smoking rates, and now the same is true for obesity.”


  1. Brown, K.F., Rumgay, H., et al (2018) The fraction of cancer attributable to known risk factors in England, Wales, Scotland, Northern Ireland, and the UK overall in 2015, British Journal of Cancer, doi: 10.1038/s41416-018-0029-6.