Researchers have revealed that the breast cancer risk in postmenopausal women is a function of waist circumference, independent of body mass index (BMI), which means that whether a woman is pear shaped or apple shaped makes no difference.
This is because BMI is a numerical value that’s calculated from a person’s height and weight (though some calculations include age and gender). But as you can see, these features of the calculation have nothing to do with the shape of a woman’s body.
A woman can have a pear shape and a BMI value equal to a woman with an apple shape.
As a personal trainer, I work with women of all kinds of body shapes: pear, apple, buff, skinny-fat, “average,” you name it. I found this study quite interesting because historically, studies have shown that the pear shaped person has a lower heart disease risk than the apple body.
The study about breast cancer comes from the American Cancer Society and focused on mostly white women. The study was not able to verify previous findings that body shape alone is an independent risk for breast cancer. The full report is in Cancer Causes, and Control (April 2014).
The report points out that, indeed, many studies have linked abdominal excess weight or obesity to heart disease, type II diabetes and some cancers including breast. The trend was to conclude that an apple shape (excess fat concentrated in a person’s middle) is more harmful than the pear shape (fat loaded more in the thighs, hips and butt).
Mia Gaudet, PhD, and her team analyzed data from almost 29,000 women. A strong correlation was unveiled between postmenopausal breast cancer risk and waist size. But the association vanished once BMI was adjusted for.
“The message is that if you have a high BMI,” says Dr. Gaudet, “regardless if you are pear or apple shaped, you are at higher risk of breast cancer.” This study looked at BMI and waist circumference together.
Women who’d like to shrink their waist size to lower breast cancer risk need to step away from the crunch machine and pick up some heavy barbells. I’m serious. Heavy barbell work will shear more fat off the entire body than will folding-movements that isolate a tiny muscle group. As for what’s “heavy,” this is a highly relative term, and is defined as that which is difficult to lift/pull for between eight to 12 repetitions. Best barbell (and dumbbell) exercises include the deadlift, squat and bench press.