Each year thousands of UK cancer cases could be prevented through better diet, less alcohol and weight management The Daily Telegraph has reported. The statement is based on a new report by the World Cancer Research Fund (WCRF), discussing ways to reduce lifestyle factors that raise the risk of major cancers.
Several other news sources have featured coverage on the report, with The Guardian saying that most cancer is not inevitable and that 26% of British cancer cases could be prevented through lifestyle change. BBC online says the experts behind the report believe urgent action is needed to avert a crisis, with cancer rates set to increase due to an aging population, rising obesity, falling physical activity and growth in eating unhealthily.
Where did the news reports come from?
The news is based on a policy report by the World Cancer Research Fund recommending a number of measures to reduce rates of preventable cancer, sometimes referred to as ‘lifestyle cancers’. This review focused on the possible implementation of population and community programmes which had been shown to be effective in an earlier WCRF report.
The first expert report, a systematic review of scientific research, was published in late 2007. It looked at the evidence that specific dietary patterns, nutrition and physical activity can prevent cancer. The report concluded that globally, each year millions of cancer cases are preventable.
In the preface of this new report, Professor Michael Marmot explains that although the recommendations of their first report were “rather straightforward”, they are hard to implement. Simply conveying information on risks and benefits has, in the past, shown limited impact on individual food and activity choices. In response, the WCRF has drawn up these recommendations so that governmental and public bodies can play a role in encouraging individuals’ lifestyle changes.
How were these reports compiled?
The WCRF’s report ‘Policy and Action for Cancer Prevention. Food, Nutrition, and Physical Activity: a Global Perspective’ involved over 100 scientists from 30 different countries.
In the study an expert panel of 21 respected scientists worked for five years to assess a body of research, firmly basing their conclusions and recommendations on the scientific evidence.
The second review, ‘Policy and Action for Cancer Prevention’, looked at the 10 simple messages from this first report: stay lean throughout adult life, limit foods and drinks that promote weight gain, be physically active, limit red meat consumption, avoid processed meat, eat non-starchy vegetables and fruit, limit alcohol consumption, limit salt intake and breastfeed children.
In this second report, researchers looked for relevant evidence and evaluated how these recommendations could be implemented in areas of the physical environment, economic, social and personal dimensions. The recommendations to be included in the report were then agreed by a panel of 23 experts.
What recommendations does this new report make?
The large report makes 48 recommendations to reduce cancer rates. These address the roles of public bodies including government, schools, medical professionals, employers and the media. It also addresses the role played by members of the public themselves. The WCRF says these types of organisations can share responsibility for taking action, with individuals taking responsibility for the choices they make as consumers and citizens.
Among these 48 recommendations is the advice for schools and workplaces actively to encourage physical activity and ban unhealthy food. The WCRF also recommends that governments introduce widespread walking and cycling routes to encourage physical activity, and that those who do the weekly food shopping for their family should check food labels to make sure the food they buy is healthy.
Other recommendations include proposals that:
- Schools, workplaces and institutions should not have unhealthy foods available in vending machines.
- Governments should incorporate UN recommendations on breastfeeding into law.
- The food and drinks industry should make public health an explicit priority at all stages of production.
- Industry should give a higher priority for goods and services that encourage people to be active, particularly young people.
- Health professionals should take a lead in giving the public information about public health, including cancer prevention.
What did the new report say about preventable cancers?
The report estimates the percentage of cancers that could be prevented in four countries in the UK, US, Brazil and China. Estimated proportions of UK cancers that were preventable:
- 67% of mouth, pharynx and larynx cancers,
- 75% of cancers of the oesophagus,
- 33% of lung cancers,
- 45% of stomach cancers,
- 41% of pancreatic cancer,
- 16% of gallbladder cancer,
- 43% of bowel cancer,
- 17% of liver cancer,
- 42% of breast cancer,
- 56% of endometrial (womb) cancer,
- 20% of prostate cancer,
- 19% of kidney cancer,
- 39% of these 12 cancers combined, and
- 26% of all cancers.
What interpretations did the researchers draw from these results?
The authors of the report say that, after not smoking, maintaining a healthy lifestyle is the most important thing you can do for cancer prevention.
Of lifestyle factors, maintaining a healthy weight is particularly important. For example, in the US, 16% of bowel cancer cases in men and 17% of breast cancer cases in women could be prevented just by being in the healthy weight range.
The authors say that there are more recommendations for government than any other group, and this reflects the special role the government plays in public health.
For the industry groups, the authors say that recommendations are aimed at owners, directors, executives and other decision-takers in relevant industries such as food and drink, urban and rural planning and development, construction and engineering, and entertainment, leisure and sports. For all these groups, this report proposes that a new balance is struck in favour of health.
What does the NHS Knowledge Service make of this report?
This is a thorough report that appears to have covered all relevant dimensions of a population approach to the prevention of cancer, except perhaps smoking cessation programmes, which the WCRF says is not within its remit.
Fortunately, many of the behaviour changes targeted are also relevant for helping to prevent other chronic diseases such as heart disease and diabetes. This means individuals wishing to cut their cancer risk will also cut their risk of several other health problems by making just one change.
The authors also caution that, because of the way that different lifestyle factors are interlinked, it is not possible simply to add the preventability estimates from smoking and other lifestyle factors together to get a combined total.
Commentators have said that the report “will play an important role in helping to set the agenda for how policy can reduce the number of cancer cases”.