Waistline and body type

What Your Waistline Can Tell Your Doctor

by Tanya Zilberter, PhD

And you thought narrow waist was only important for models!

The National Institutes of Health guidelines indicate that within each BMI category, the health risk increases in a graded fashion so that those with high waist circumference are at a greater health risk than those with narrower waistline. Why?

First of all, because the waist circumference, as simple as it is, tells a lot about body fat types, distribution, and harmful health effects. If you look at a picture of human skeleton, you’ll see that in the waist region there’s absolutely nothing below the ribcage but a spinal column — so it doesn’t make any sense to talk about waists of tall and short people as well as about large and small frames. Even bodybuilders with muscles bulging all over the body have narrow waists.

Another thing about the “apple” body shape is that the fat concentrated around the middle is a different, worse type of fat than the fat on thighs or upper trunk. People having the “apple” body shape are particularly prone to developing abnormal lipid profiles and insulin resistance. The cells here (adipocytes) are overly sensitive to stress, alcohol intake, and smoking.

When metabolic syndrome is present, the abdominal fat cells seem to have a high density of several important hormone receptors which stimulate fat storage and inhibit lipolysis, leading to further abdominal fat depositing — thus creating a vicious cycle. However, here’s the good news: these same fat cells are also very sensitive to dietary carbohydrate restriction. You might remember the South Beach diet’s slogan: “Belly fat goes first!” Indeed it goes first when the dieters cut down on refined carbohydrates.

An interesting thing about abdominal fat is that although a diet can reduce belly fat total volume, it fails to reduce the size of fat cells here, unless exercise is added to the equation, according to new research from Wake Forest University Baptist Medical Center.

Another interesting thing was reported by researchers from the Cooper Institute, Dallas, TX. They put sedentary obese women on exercise programs of different intensities: 4, 8, or 12 kcal per one kilogram of body weight per week — and showed that although only the highest intensity was good for weight loss, any exercise intensity was good for shrinking the waistline.

Calories or Kcalories?

Let me explain the calorie numbers. Kcal in fact means 1000 calories, but since in popular literature we usually deal with 1000s of calories, people are used to thinking of them as just calories. However, technically they are so-called “big calories” or Calories with capital C.

To give you an idea what it takes to burn 12 kcal/kg/week, here’s an example. A man weighing 170 pounds (77 kg) and exercising at 12 kcal/kg/week burns 924 Calories every week and can do this by walking for almost three hours or running at 6 mph for one hour .

Sources

International Journal of Obesity, August 2006
Medicine & Science in Sports & Exercise, May 2006