Excess body fat is a health hazard, but the distribution of that fat may be the best predictor of future health risks. The results of a new study published in the September issue of the American Journal of Clinical Nutrition indicate that how much fat a person has is less important than the location of fat when it comes to determining risk for cardiovascular disease.

For the study, researchers at Wake Forest University Baptist Medical Center evaluated body fat distribution in nearly 400 adults between the ages of 47 and 86. They found that the amount of non-subcutaneous fat — the fat deposited around organs and between muscles — was directly correlated to the amount of hard, calcified plaque present in the body.

Calcified plaque is associated with the development of atherosclerosis, or hardening of the arteries, a condition that increases the risk of developing heart disease. Among American men and women, heart disease is the leading cause of death.

Over the past decade, dozens of studies have demonstrated the importance of body shape and body fat distribution in determining a number of health risks. Individuals who tend to store body fat around their waists are considered to be apple-shaped because, like the fruit, they're largest around the middle. Pear-shaped individuals, on the other hand, store more of their excess body fat around their hips, buttocks and thighs.

How do you know which fruit you most resemble? The answer lies in a measurement called the waist to hip ratio (WHR). To determine your WHR, all you need is a tape measure and a calculator.

Start by standing erect, and measuring your waist at a point about one inch above your navel. Next, measure your hips by placing the tape measure around your buttocks. To determine your WHR, divide your waist measurement by your hip measurement.

If your WHR is 0.8 or less, your body can be classified as pear-shaped. If your WHR is higher than 0.8, your body shape falls into the apple category. To a large degree, the shape of your body determines which type of fat you'll accumulate most when you gain weight.

Body fat comes in two main varieties: subcutaneous fat, which lies just under the skin, and non-subcutaneous fat, which is stored deep in the torso and the muscles of the body. The most clinically significant type of non-subcutaneous fat appears to be visceral fat, which surrounds the organs, including the heart and liver.

While pear-shaped individuals tend to have more subcutaneous fat, people who are apple-shaped tend to have more visceral fat.

Subcutaneous fat is close to the surface of the body. It's the visible fat you can pinch with your fingers. While this type of fat may be cosmetically unappealing, it typically doesn't represent a significant health hazard.

Excessive visceral fat is considered far more dangerous. Packed away in the abdomen, it isn't always visible from the outside, but this type of fat is far more metabolically active than subcutaneous fat, and most of its actions are harmful to the body.

A growing amount of scientific evidence suggests that excess visceral fat increases the risk for a variety of debilitating diseases. Not only does it boost levels of triglycerides and low-density lipoprotein (LDL), it also lowers levels of cardio-protective high-density lipoprotein (HDL) cholesterol.

Several studies have shown that regardless of total body weight, apple-shaped individuals have a greater risk of heart disease than those who are pear-shaped. Because the subcutaneous body fat that collects around the hips, thighs and buttocks is typically associated with higher levels of HDL, pear-shaped individuals appear to have greater protection against cardiovascular disease.

Compared to pear-shaped individuals, those who are apple-shaped are significantly more likely to develop diabetes. Unlike subcutaneous fat, visceral fat reduces the body's sensitivity to insulin, the hormone responsible for maintaining normal blood-sugar levels.

Regardless of body shape, the risk of developing heart disease and diabetes increases with every inch added to the midsection. The good news is that with positive changes in diet and exercise habits, it's entirely possible to reduce waist circumference.

Studies show that losing just two inches from the midsection can lower total cholesterol levels and blood pressure. When it comes to protecting yourself from heart disease and diabetes, losing a few pounds is great, but losing a few inches from your waist may be even better.

Rallie McAllister is a board-certified family physician, speaker and the author of several books, including "Healthy Lunchbox: The Working Mom's Guide to Keeping You and Your Kids Trim." Her website is www.rallieonhealth.com. To find out more about Rallie McAllister, M.D., and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate Web page at www.creators.com.

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