The chart below is from the study I cited in yesterday’s post. You can click it to make it bigger.
The numbers (percents) in the graph represent the population-attributable-fraction, “an estimate of the proportion of reduction in cancer that would occur if exposure to a certain risk factor were reduced to the optimal exposure distribution.”
So, regarding exercise, you might be able to reduce cancer deaths worldwide by 2% if everyone’s behavior fell in line with “optimal exposure.” (The example they gave for optimal exposure for exercise was “2.5 hours/week of moderate-intensity physical activity.”) 2% sounds small, but it equates to ~135,000 cancer deaths each year.
Look at smoking. I think … you may want to plan on a cancer diagnosis down the road if you smoke, or if you are exposed to second-hand smoke. It is that powerful a risk factor.
Here’s a clip of Yul Brynner from his interview on Good Morning America 9 months before his death in 1985. After he died, The American Cancer Society took 29 seconds of the interview and produced this public service announcement:
“Now that I’m gone, I tell you don’t smoke. Whatever you do, just don’t smoke. If I could take back that smoking, we wouldn’t be talking about any cancer. I’m convinced of that.”
One more thing about that graph. If you remove the bar for smoking, which lifestyle behavior rises to the top? Low fruit and vegetable consumption. Take smoking out of the picture and diet becomes the strongest predictor of whether we get cancer.