It’s not just for heart disease any more

When I see patients for physicals these days, I spend time discussing their risks for various illnesses. Part of this discussion includes a review of their Body Mass Index (BMI) and Waist to Hip Ratio (WHR), and usually this discussion is in the context of risk of heart disease, high blood pressure, diabetes and stroke.

Recently one patient who has a very high BMI but a good WHR asked about the risk for other illness. I mentioned that there was an increased risk of cancer in people who are overweight or obese.

Researchers from the American Cancer Society (N Engl J Med 2003;348:1625-38) analyzed participants in the Cancer Prevention Study II, which began in 1982 and initially included over one million Americans from every state, the District of Columbia, and Puerto Rico. In the baseline questionnaire, participants were asked to report their current weight, their weight one year before, and their height. Then they were followed until the end of 1988. For this study, researchers excluded those who were below normal weight at the beginning of the study, had a history of cancer, those whose height and weight information was incomplete at the beginning of the study, and those who did not provide information on their race or their smoking history. They were left with 404,576 men and 495,477 women.

After all the analysis was said and done, those whose Body Mass Index (BMI) was over 40 had a risk of death from cancer--of all types and locations--that was 52% higher for men and 62% higher for women than those whose weight was within the "normal" range of 18.5 and 24.9 BMI. For those whose BMI was between 30 and 35 (those who are usually termed "obese"), the increased risk of death from cancer was only an additional 9% for men and 23% for women, while those who are termed "very obese" (BMI between 35 and 40) had an increased risk of 20% and 32% for men and women respectively.

What this means for you

Here’s another reason to maintain a healthy body weight. Is your Body Mass Index putting you at an increased risk for cancer?

First posted: June 23, 2006