The link between obesity and cancer

NORTH PHILADELPHIA (WPVI) -- People have many reasons to lose weight - to cut their blood pressure or blood sugar, to lessen joint pain, or just have more stamina.

But few say they want to reduce their cancer risks. Medical experts say they should.

It's simple math, but not usually on our minds when stepping on the scales.

"Every roughly 10 percent increase in their body weight, their risk of certain types of cancers goes up by about 10 percent or so," says Dr. Neil King, a bariatric surgeon at Temple Health.

Dr. King says more than a dozen cancers are directly linked to obesity, such as breast cancer after menopause, endometrial cancer, ovarian cancer, pancreatic cancer, colorectal cancer, and multiple myeloma.

"Most people think of fat as sort of an inactive tissue, when in reality it's very biologically active," he says.

Fat increases estrogen, a hormone that drives some cancers.

Fat also causes chronic low-grade inflammation throughout the body which helps malignant cells multiply.

Bariatric surgery can cut cancer risks 33 to 50 percent, however, the first step comes well before the operating room.

"To start getting that patient to make changes in their diet, and some behavioral changes in their lifestyle," says Victoria Brown, R.D., L.D.N. a dietitian in the Temple Health bariatric program.

Changes like eating more whole foods like fruits and vegetables can make a huge difference.

"Half of your plate should be fruits and vegetables," says Brown.

Decreasing processed and calorie-dense foods, like snacks, fast foods, and especially sugar-sweetened drinks.

"Soda, even 100 percent fruit juice - all these beverages have tons of added sugar and they're just adding extra calories," she notes.

Making time for physical activity is another important change.

When improvements are made before surgery, it's easier to make them habits afterward.

"Patients really have to change their relationship with food and their relationship with exercise in order to sort of prepare for this process, because it is a lifelong process," says Dr. King.

And the benefits aren't limited to the overweight patient. When one person in a family makes changes, everyone tends to get healthier.