Cancer risk: Is it right to compare obesity to smoking?

Cancer Research UK’s recent campaign compares obesity to smoking as a cause of cancer. Is this a fair comparison?

Published: July 19, 2019 at 7:00 am

Controversy, the nirvana of any campaign, brings wide reach and lots of media attention. Cancer Research UK (CRUK) has attracted plenty, its new ads loitering at bus stops and flooding social media with images of old-fashioned fag packets emblazoned with the simple message ‘obesity is a cause of cancer too’.

As well as increasing awareness, CRUK say the goal is to protect children against ‘junk’ food adverts by getting the Government to commit to a 9pm watershed on TV. However, the new campaign may be doing more harm than good, with over 11,500 people signing a petition calling for its immediate end.

Smoking and obesity are fundamentally different: smoking is a behaviour (something people do) whereas obesity is a physical outcome (a measurement of body mass). Both are complex social issues which require good government policies to promote health.

But at an individual level, the most effective way to reduce smoking-related cancers is to stop smoking. This abstinence approach is impossible to replicate for obesity. People can’t just stop eating; neither can they simply lose weight. In fact, although short term weight loss is possible, weight loss trials show that, in the long term, most people put it back on. This leaves many of us in an unhealthy cycle of yo-yo dieting.

Body weight and size are influenced by many different factors both at a personal level (genetics, psychology) and a societal level (built environment, government policies). For instance, some people are genetically predisposed to have a higher body mass and be more resistant to weight loss than others. This means societal factors affect some people more than others and weight management isn’t the same for everybody.

Listen to geneticist Dr Giles Yeo explaining why obesity isn't a self-control problem:

Regardless, the sight of these cigarette-style posters encourages people to associate the stereotypes of smoking with obesity, in particular, that obesity is the result of irresponsibility. The simple fact is that neither smoking nor obesity are merely outcomes of individuals making bad choices. In this way, this campaign encourages weight stigma and discrimination. Smoking is considered to be unfairly damaging the health of others – the same cannot be said for obesity. However, as the ensuing media debate has shown this comparison encourages the same moral outrage. This creates a very hostile environment for people of higher weights.

We’ve all seen media stories that go something like this: a culture of political correctness is allowing fat people to live in denial because people are too afraid of hurting their feelings with hard truths. This framing is patronising clickbait that masks reality. It’s also counterproductive: numerous studies show weight stigma promotes calorie consumption, exercise avoidance and weight gain.

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If weight stigma was effective, it would be fair to say the dominant anti-fat culture we already live in would prevent people putting on weight. But it doesn’t. Fear of weight stigma also stops people going to see healthcare professionals and leads to cancer going undiagnosed. Clearly this should be a concern for CRUK.

So how could the CRUK campaign be improved? If policy change is the aim and the government are the target, then logically the CRUK campaign should focus on building public pressure to force government action. The campaign should educate the public about how inequality, unemployment and lack of food industry regulation increase the risk of cancer, and encourage people to support their call for social change. Rather than increasing hostility towards people of higher body weights, CRUK should bring people together in a call for positive action.

Response from Michelle Mitchell, chief executive of Cancer Research UK:

“Obesity is a complex issue, with no single cause or solution. We’re comparing smoking and obesity to show how Government-led change can help people form healthier habits, not to compare tobacco with food. The campaign aimsto raise awareness of the link between obesity and cancer, and bring about policies thatmakehealthy options accessible for everyone, including restricting junk food advertising and price promotions on the most unhealthy products. It isn’t meantto make anyone feel bad about their weight, or make anyone think negatively about people who are overweight or obese.

“We have adopted many of the World Obesity Federation principles and signed up to the Obesity Health Alliance’s position statement on weight stigma, and continue to engage with experts on these complex issues.

While we don’t want to cause any offence, we’re spreading an important message – and having run this campaign several times, we’ve surveyed thousands of people with a range of body weights, and 84 per cent agree it’s an important message that needs to be communicated.”

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