Obesity to blame for 'more than one in ten' bowel cancer cases

Charity Cancer Research said the figures underlined the need for tough restrictions on retailers promoting junk food sales through multi-buy offers, which it said were luring shoppers to "pile on the pounds".

An evaluation carried out by Cancer Research UK estimated that 4,800 cases of bowel cancer in Scotland over the past decade had being caused by patients being too heavy.

The calculations also indicate that while overweight and obesity was behind an estimated 10.5 per cent of bowel cancer diagnoses in 2005, by 2015 that had crept up to 12.1 per cent as the prevalence of obesity within Scotland's population increased.

The estimates have been calculated by combining data on overweight and obesity prevalence from Scottish Health Surveys, official statistics on bowel cancer and research on the relative risk of developing bowel cancer according to body mass index (BMI).

Bowel cancer is the third most common form of the disease in Scotland. There are around 3,800 diagnoses of bowel cancer a year in Scotland, with the disease claiming around 1,600 lives annually. The latest research suggests that obesity could be responsible for around 460 cases each year and nearly 200 deaths.

Professor Linda Bauld, Cancer Research UK’s cancer prevention expert, who is based at Stirling University, said the findings were a "huge worry".

She added: “Shoppers are bombarded with multi-buy offers every time they set foot in a supermarket. Unfortunately, instead of encouraging us to fill our trolleys with food that’s good for us, these ‘deals’ persuade us to stock up on foods that pile on the pounds.

“Cancer Research UK believes restricting these multi-buy offers on unhealthy foods and drinks would go a long way to improving the health of the nation. The Scottish Government can and must do more and its forthcoming strategy is a once in a generation opportunity to introduce measures that will have a profound impact on our lives.”

Prof Bauld is expected to raise the issue in a presentation to the board of Food Standards Scotland in Aberdeen tomorrow.

Scientists have yet to unravel exactly how being overweight or obese can cause bowel cancer, but insulin resistance - which also leads to diabetes - is believed to be a likely factor.

Geoff Ogle, chief executive at Food Standards Scotland, said: “There is no single ‘silver bullet’ solution to these issues, which is why Food Standards Scotland has put forward a broad range of measures to Scottish Government to tackle Scotland’s poor health and diet.

“A soft drinks industry levy has already had some effect and we have seen soft drinks producers reducing the sugar content of their products as a result. However, Food Standards Scotland remains of the view that a tax on sugar content across other food and drink should also be introduced.

“Our recent recommendations include calls for regulation of promotions, promotion of healthier options, a reduction in portion sizes and more effort from the out of home sector to increase the availability of healthier options and provide clear calorie information for consumers.

“In our view, regulation helps to create a level playing field for industry, and without it, we face the very real prospect of increasing diet-related ill health, including cancer-related diseases, which place unsustainable burdens on the NHS and our economy.”

Scotland's public health minister, Aileen Campbell, said: “We will consult on our new diet and obesity strategy this year, building on our wide range of activity to make it easier for people to be more active, eat less, and eat better. As part of that, we are looking at what further effective actions we can take within the powers available to us, including action on the use of multi-buy promotions.

“We are also engaging with the food and drink industry on action to offer healthier choices, rebalance promotions, and reformulate products, with a focus on reducing calories, salt, fats and added sugar."