If you are like most women, you’ve thought a lot about your body shape over the years. From the time teenage hormones kick in, our waist, hips, thighs, and breasts take on an inflated significance. But what most women don’t know is that body shape is the single most important predictor of your future health. While most health experts have focused almost exclusively on weight, the truth is that shape beats weight when it comes to your risk of heart disease, type 2 diabetes, metabolic syndrome, breast cancer, osteoporosis, depression, and other disorders.

All women can be categorized as having either an “apple” or a “pear” body shape, depending on where you carry excess body weight. If your waist is your problem area, then you have an apple shape. But if fat tends to accumulate around your lower body—around your hips and thighs—then you have a pear shape. Although most women know all too well what part of their body collects fat, the scientific definition of body shape requires knowing your waist-to-hip ratio, which takes just three simple steps:

• Measure around your waist with a flexible tape measure. If you have a visible waist, measure around the narrowest part. If you don’t have a waist, measure around the widest part of your middle, usually about one inch above your navel. Hold the tape measure loosely, without putting pressure on the skin. Don’t suck in your gut! That number is your waist circumference.
• Measure around your hips—not where the bones of your pelvis jut out, but about three to four inches lower. You should be measuring around your buttocks, not above or below it. If you have any doubt, take the measurement at the widest point of your lower body, which may include your “saddlebags” if you are pear-shaped. That number is your hip circumference.
• Divide your waist circumference by your hip circumference to get your waist-to-hip ratio, or WHR. For example, if your waist circumference is 36, and your hip circumference is 34, divide 36 by 34 to get a WHR of 1.06.

If your WHR is 0.80 or lower, your body is classified as pear-shaped. If your WHR is higher than 0.80, your body is classified as apple-shaped.

How Important Is Body Shape?

Although we’ve known for decades that these different body shapes existed, only now are their causes and related health risks becoming clear. The startling discovery is that these two categories of women—apple-shaped and pear-shaped—are as physiologically different from each other as women are from men. The reason is fat.

Fat comes in two main varieties: subcutaneous fat, which is located under the skin; and visceral or abdominal fat, which packs itself around the inner organs of your abdomen. Subcutaneous fat, being closer to the surface, is always easy to see—cellulite, for example, is subcutaneous fat. Visceral fat, on the other hand, is not always visible from the outside. It jams up against your intestines, kidneys, pancreas, and liver (and sometimes even inside your liver). We all need some visceral fat because it protects our internal organs, acting both as shock absorber in case of trauma, and as insulator to help us conserve body heat.

While subcutaneous fat may be visible and annoying, it is relatively harmless. In fact, fat in the pear zone—hips, thighs, and buttocks—helps to protect you from disease. Scientists believe that pear-zone fat acts like a fat magnet, trapping certain fats from the foods you eat and keeping them from escaping into your bloodstream, where they can damage your arteries.

Excess visceral fat, on the other hand, is more metabolically active than subcutaneous fat, and most of what it does is harmful to the body. It decreases insulin sensitivity (making diabetes more likely), increases triglycerides, decreases levels of HDL cholesterol (the good one), creates more inflammation and blood clotting, and raises blood pressure—all of which increase your risk of heart disease. Instead of trapping fat, visceral fat releases more free fatty acids into your bloodstream, further increasing your risk of both diabetes and heart disease, as well as certain cancers. This is why apple-shaped women, who carry their weight around their waists, have an increased risk of metabolic and vascular diseases.

Although pear-shaped women are protected from heart disease and diabetes, they have health risks of their own. For example, pear-zone fat produces a less potent form of estrogen than apple-zone fat, making pear-shaped women more likely to experience more severe symptoms of menopause, and to develop osteoporosis. Plus, pear-shaped women have less male hormone than apple-shaped women, so they are likely to have lower bone mass density than apple-shaped women to begin with. Pear-shaped women are also more likely to develop eating disorders, probably because society tends to value the narrow hips and slender legs that are impossible for pear-shaped women to achieve, even with liposuction.

Health Tips for Your Body Type

No matter which body shape you have, how old you are, or how much you weigh, there are many things you can do to decrease your personal disease risk. Diet and exercise are only part of the equation—medical monitoring is critical, as is a change in mind-set. You need to stop thinking of your weight problems, and learn to accept yourself as a woman with a figure. Every woman can become stronger, look better, and feel healthier.