If you consider yourself fairly trim—perhaps a woman who is 5’7’’ and weighs about 135 to 140 pounds, or a man 
who measures an even 6 feet and weighs 170 pounds—you may think you don’t have to worry about your weight and your health. You may need to think again.
We’ve all been trained to assume that a lower BMI, or Body Mass Index, always equals better health. But recent research from the Mayo Clinic says what really matters is body fat, not weight or BMI. You may appear to be in pretty good shape, but form isn’t always an accurate indicator of body fat. And if you carry a relatively high percentage of body fat – more than 20 percent for men or 30 percent for women—you may still be at increased risk for serious health problems such as diabetes or heart disease.