Some of the abdominal fat is located in the fatty tissue just beneath the skin. This subcutaneous fat behaves like the fat elsewhere in the body; it's no friend to health, but it's no special threat either. However, belly or visceral fat, which is located around the internal organs, can damage your health. One way to evaluate body fat is to measure height and weight, then calculate body mass index (BMI). This is now the standard way to diagnose obesity. Another simple method uses the ratio of the waist and hip measurements. But many experts are turning to an even simpler technique: waist circumference. Because it involves one measurement instead of two, it's more accurate and reproducible. And new research suggests that this simple measurement is the best way to tell who is at risk for the serious consequences of obesity. Scientists thought visceral fat was dangerous because it was linked to elevated stress hormones, which raise blood pressure, blood sugar levels and cardia...