A recent post from CNN online deals with the best way to measure body fat. Click here to see article. I believe Dr. Jampolis does a really nice job comparing and contrasting the different methods to measure body fat, and I agree with her statement that body fat is a better determinant of health than is body mass index or BMI.
BMI is easy to calculate and that’s its main benefit. You can have a high BMI if you have a lot of muscle for your height and frame, and many athletes have high BMIs, but are still quite healthy.
In our practice we use the DEXA scan. DEXA is the only technology that measures visceral fat. Visceral abdominal fat (VAT) is the fat in the belly and in the organs. It is the fat that is dangerous to our health.
The DEXA scan is primarily used to determine bone density, but with additional software can very accurately measure body fat. In our opinion it is the most accurate method currently available, plus has the additional advantage of measuring bone density.
The nice thing about the DEXA scan is we can accurately measure lean body mass and percent body fat by body region. We can tell you how much fat you have in your right arm, left leg, and so on. That’s important to know because excess fat around the belly is more harmful to one’s health than excess fat around the hips or other areas. Of course, simply standing in front of the mirror naked is probably enough to know where you have excess body fat.
Skinfold calipers are frequently used in health clubs, and can provide a reasonably good estimate of body fat when done by an experienced technician, but results can vary dramatically from one technician to another. Skinfolds usually underestimate the true body fat.
Underwater weighing had long been the gold-standard, but many patients, especially middle age and older have a difficult time exhaling air out of their lungs and then holding their breath underwater long enough while the test is being conducted, and if anything underwater weighing tends to overestimate body fat based on my previous experience using this method to measure body fat.
Regardless of the method being used, it’s important to track body fat with serial measurements. Periodically measuring body fat can serve as a great motivator in helping people comply with a nutrition and exercise program ultimately leading to better health.
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