About one-third of the most common cancers could be prevented in wealthy countries through healthier lifestyles, says a team of international researchers. And governments and industry need to help, they conclude in a sweeping report issued Thursday.
About a quarter of cancers could also be prevented in poorer countries if they adopted better diets, weight control and exercise, according to the report, entitled "Policy and Action for Cancer Prevention."
While individuals have a role to play, governments and industry need to begin co-ordinated efforts to reduce the burden of cancer.
The report, released jointly by the American Institute for Cancer Research and the World Cancer Research Fund, is as good an estimate as possible about the proportion of preventable cancer cases, says panel member Dr. Tim Byers, of the University of Colorado, Denver.
"On a global level every year, there are millions of cancer cases that could have been prevented. This is why we need to act now before the situation gets even worse," he said in a statement.
The document is a follow-up to an October 2007 report by the two groups, which evaluated over 7,000 studies on cancer rates and came away with 10 recommendations for lowering cancer risk.
While the recommendations in that report bear repeating, this report emphasizes the message that all sections of society need to make cancer prevention a higher priority, says Dr. Shiriki Kumanyika, of the University of Pennsylvania School of Medicine.
"The 2007 expert report identified the specific choices that people can make to protect themselves against cancer, but actually making those healthy choices remains difficult for many people," she said.
"The policy report takes the next step; it identifies opportunities for us as a society to make those choices easier."
The other players in society that need to take a leadership role include: government; industry; media; schools; workplaces and institutions; and doctors.
This report makes 48 recommendations for those sectors to help individuals cut their risk of cancer. Among them:
- Governments should require widespread walking and cycling routes to encourage physical activity.
- Doctors and other health professionals should better inform patients about public health, including cancer prevention.
- The food and drinks industry should make public health an explicit priority.
- Schools should actively encourage physical activity and provide healthy food for children.
- Schools, workplaces and institutions should not have unhealthy foods available in vending machines.
- Industry should give a higher priority for goods and services that encourage people to be active, particularly young people.
- People should use independent nutrition guides and food labels to make sure the food they buy for their family is healthy.
The report focused only on the proportion of cancers that could be prevented through diet, physical activity and weight management.
It did not include smoking, which alone accounts for about a third of cancers, the report authors say.
Sir Michael Marmot, chair of the report panel, says that by making relatively straightforward changes, we can significantly reduce the number of cancer cases around the world.
"This report is relevant to everyone from heads of government to the people who do the weekly food shopping for their family and the overall message is that everyone needs to make public health in general, and cancer prevention in particular, more of a priority," he said in a statement.
