Studies Link Obesity and Breast Cancer

In case you needed more of a reason to keep an eye on your weight, recent research has found that, in general, obesity is linked to cancer. For obese women, especially those who have gone through menopause, this means an increased risk of breast cancer. Though experts can't yet explain to us why the link is there, they are working hard to figure it all out.

What we do know is that the higher your Body Mass Index (BMI) the measurement of your weight against your height squared, the more chance you have of developing cancer. This was confirmed by an extensive data review of 140 studies by scientists at the University of Manchester in England earlier this year. Other work had found the same links between cancers and more body fat, and in 2007 a report issued by the American Institute of Cancer Research and the U.K.-based World Cancer Research Fund concluded that body fat is associated with an increased risk for several different types of cancer.

If that wasn't enough a recent study at the University of Texas M.D. Anderson Cancer Center, found more than two-thirds of women with stage III locally advanced breast cancer were overweight (32%) or obese (34%). The research also found that a greater number of obese patients were likely to be diagnosed with inflammatory breast cancer - a rare and more deadly form of this type of cancer.

The extra weight increases your risks, and brings other problems too. It's harder to spot tumors (or recurrences) early, and women who are overweight or obese are known to avoid checkups altogether. Once a cancer has been spotted, the added weight can cause problems figuring the best chemotherapy dose - plus the more weight the more medicine that must be used, and the more intense any side effects will be.

"We know that women who are overweight at the time of breast cancer diagnosis have a higher risk of recurrence than lean women, but the reasons for this are not clear," says Dr. Jennifer A. Ligibel of the Dana-Farber Cancer Institute in Boston. "Recent evidence suggests that high insulin levels, which are common in overweight women, may be involved in the increased risk of breast cancer recurrence."

Debbie Saslow, director of breast and gynecologic cancer at the American Cancer Society, points out that it's not completely clear what role obesity plays in breast cancer risk. According to ACS numbers, about 182,500 women in the U.S. will be diagnosed with invasive breast cancer during 2008. Right now there are almost 2.5 million breast cancer survivors in the United States.

In all this doom and gloom, there is some rather encouraging news. Studies have shown that exercise - 30 to 60 minutes of moderate-to-high intensity activity each day - cuts breast cancer risk according to Colleen Doyle, director of nutrition and physical activity at the American Cancer Society. You don't have to go from no workout to a full hour of high intensity activity in one leap - in fact, if you're really out of shape and very sedentary, talk with your doctor first, before you start getting more active.

Once you get the okay, adding activities like walking is a great way to get started. Build your routine, both in time and intensity slowly, over weeks or months, until you are able to do the 30 minutes recommended. Not only will you notice that you're feeling better... stronger and more confident, but you'll be doing one of the best things you can to lower your risk of breast cancer and give yourself many healthy, happy years.