A third of all cancer cases in Canada are preventable, according to a new study.
The Canadian Population Attributable Risk of Cancer (ComPARe) study brought together a multidisciplinary team of experts to estimate how many Canadian cancer cases are caused by preventable factors. They looked at the incidence of over 30 types of cancer diagnosed in 2015, then they probed into whether they had been caused by any of over 20 modifiable risk factors, like what we eat and drink, and whether we are physically active and maintain a healthy body weight.
The study found that the top five preventable risk factors for cancer are smoking cigarettes, physical inactivity, excess weight, low fruit consumption, and sun exposure. And the most preventable cancer was cervical cancer, thanks largely to the HPV vaccine.
The study was led by University of Calgary researchers Christine Friedenreich and Darren Brenner. ComPARe’s partner institutions are Alberta Health Services, Carleton University, Cancer Care Ontario, Canadian Cancer Society, McGill University, Cancer Epidermiology and Prevention Research, McMaster University, Occupational Cancer Research Centre, Oregon State University, and Queen’s University.
The good news is that there are steps anyone can take immediately to lower their cancer risk. We can live smoke-free, get more active, eat better, wear sun protection, and get vaccinated. Having these numbers in hand makes a more concrete argument for making positive lifestyle changes.
Even more importantly, it gives policy makers concrete targets based on the preventable burden of disease. Think of it as a roadmap for taking action, translating a vast body of research into real world programs and policies that will make the biggest difference.
The study went one step further and projected how many cancer cases would have been preventable by 2042 if current lifestyle trends continue. If Canadians don’t switch to a different track, 111,700 cancer cases will be due to modifiable risk factors in 2042.
Amongst these risk factors, excess weight ranks highly on the list of priorities, as cancer cases due to excess weight is set to nearly triple, making it the second leading preventable cause of cancer by 2042. Solving this problem, which would have a positive impact on many health conditions aside from cancer, requires a broad approach; social, economic, physiological, environmental, and political factors will all need to be addressed.
It needs to be easier to make healthy food choices and to incorporate physical activity into the day. We need to address social stigma around excess weight so that people can access help.
Educational tools like the newly revised Canada’s Food Guide need to start from an early age, helping to curb childhood obesity and helping Canadians form good habits. Keeping an up-to-date Food Guide also gives evidence-based eating advice at any age. But access to these healthy choices also needs to be accessible, even for low-income households. It’s now well accepted that poverty is not just a social issue, but it’s also the single strongest predictor of whether people are well or ill.
A healthier population starts with disease prevention. The ComPARe study helps prioritize how to tackle the lifestyle factors that contribute to cancer. And if Canada can become a leader in decreasing its cancer cases, it could provide a plan for global change.