Men who are overweight or obese when they are diagnosed with prostate cancer are more likely to die from the disease than men who are not overweight. Even more alarming, patients with more aggressive forms of prostate cancer are even more likely to die if they are overweight.

The Kaiser Permanente study included 751 Kaiser Permanente patients with prostate cancer who underwent radical prostatectomy, an operation that includes removal of the prostate and surrounding tissue. The researchers explored the association between a patient’s Body Mass Index (BMI) and prostate cancer mortality. The study took into account tumor aggressiveness and other characteristics.

What Is Your BMI?

The study considered a BMI between 18 and 25 as healthy, a BMI of 25-30 as overweight, and a BMI over 30 as obese. Overall, men who were obese at the time they were diagnosed with prostate cancer were more than 50% more likely to die from the cancer than men with a healthy BMI.

The type of prostate cancer was also taken into account. The Gleason score measure the aggressiveness of the cancer and ranges from 2 to 10, with the highest number representing the greatest likelihood of tumor cells spreading. Men with Gleason scores of 8 or higher had even higher correlations between Body Mass Index and death.

“We found among patients undergoing surgical treatment for prostate cancer, weight at time of diagnosis is more strongly correlated with prostate cancer survival than many other factors researchers have studied in the past, including some prostate cancer treatments,” said lead author Reina Haque, PhD, a researcher at Kaiser Permanente Southern California’s Department of Research & Evaluation in Pasadena, Calif.

Important Study Triggering More Research

Additional studies are needed to determine which lifestyle modifications, such as diet or exercise, could prolong a prostate cancer patient’s life. The current study only looked at men who underwent prostrate surgery. Further investigation is needed to determine if the findings of this study apply to men who received other treatments such as radiation or hormone therapy.

In previous studies, the connection between men’s weight at prostate cancer diagnosis and likelihood of survival was based on self-reported or otherwise uncertain body weight data. This made previous claims linking obesity and prostate cancer mortality somewhat controversial. However, this study used BMI collected from actual medical records, instead of self-reported data, so this study is more convincing.

The biological relationship between obesity and prostate cancer prognosis is still not fully understood, so research is ongoing. Bottom line, this is yet another study advising you to exercise, eat right and maintain a healthy weight.