Obesity greater risk for some cancers than smoking

Author: Ingrid Torjesen

As smoking rates fall and obesity rates rise, Cancer Research UK has warned that excess weight causes more cases of certain cancers than smoking and has urged the government to take action to tackle obesity.

Almost a third of UK adults are obese, and this group now outnumbers people who smoke two to one in the UK.

While smoking is still the nation’s biggest preventable cause of cancer and carries a much higher risk of the disease than obesity, a Cancer Research UK analysis has revealed that being overweight or obese trumps smoking as the leading cause of four different types of cancer. Excess weight causes around 1,900 more cases of bowel cancer than smoking in the UK each year, 1,400 more cases caused of cancer of the kidneys, 460 more cases of cancer of the ovaries and 180 more cases of liver cancer.

Michelle Mitchell, Cancer Research UK’s chief executive, said: "As smoking rates fall and obesity rates rise, we can clearly see the impact on a national health crisis when the government puts policies in place – and when it puts its head in the sand. 

"Our children could be a smoke-free generation, but we’ve hit a devastating record high for childhood obesity, and now we need urgent government intervention to end the epidemic. They still have a chance to save lives.

"Scientists have so far identified that obesity causes 13 types of cancer but the mechanisms aren’t fully understood. So further research is needed to find out more about the ways extra body fat can lead to cancer."

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. It has also launched a nationwide campaign to increase awareness of the link between obesity and cancer.

Professor Linda Bauld, Cancer Research UK’s prevention expert, said: "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.”

Professor Dame Parveen Kumar, British Medical Association board of science chair, said: “While we are very much aware of the health risks associated with smoking, less effort has been thrown behind tackling obesity, which is now a major cause of cancer.

“The government is dragging its heels in introducing measures to restrict the advertising and promotion of unhealthy food and drink and, as such, we have reached an all-time high for childhood obesity.

“The severity of this problem must not be underestimated. As well as the pressing need to raise public awareness of the worrying link between obesity and multiple types of cancer, we need to see a reversal of the cuts to public health funding so we can prevent children and adults reaching this critical stage. Failure to do so will continue to cost lives.”