Just how big a contributor to cancer risk is obesity? Elizabeth Tracey reports


Obesity is a risk factor for several types of cancer, with a new study looking at additional metabolic risk factors to further define it, and giving rise to the idea of metabolically healthy versus unhealthy obesity. William Nelson, director of the Kimmel Cancer Center at Johns Hopkins, says the issue is even more complicated than that.

Nelson: What people call energy imbalance, which is a combination of obesity, physical activity and dietary excess, they're not all equivalent, which is where this study heads. It's emerging now is probably the largest environmental risk factor for cancer in the US and there are cancers that are clearly more heavily influenced like a lifetime of poor energy balance or obesity. What they did in this particular study is they took data from a very large number of people throughout northern europe 23,24 thousand cancers.     :32

Nelson says those with metabolically unhealthy obesity were most at risk for cancer. At Johns Hopkins, I’m Elizabeth Tracey.