Measure FAT NOT WEIGHT: How You are Misled by your BMI: Affordably Test Your Body Fat
Now that we have used the BMI calculation for many years we realize that generally you are at risk for complications of obesity if your BMI is greater than 30 kg/meter square. There are adjustments for ethnicities, but no adjustment for being male or female, although generally at each BMI men have more lean mass and women more fat mass.
1. BMI is a quick calculation, based on the fact that generally most of us have an ‘average amount of fat and muscle, but it was never intended to determine fitness or even really fatness as the only measure. It was thought up by a mathematician, and not based on scientific studies initially.
2. It is scientifically nonsensical to measusre BMI without measuring waist size, relative waist and the waist size. Women should not be over 88 cm in their waist and men should not be over 94. Waist to hip ratio is probably more important than the overall waist size. And most important is how much VAT or visceral abdominal fat you have. Visceral fat is the most harmful as it is the most metabolically active.
3. BMI calculations alone are physiologically wrong without knowing muscle and fat proportion, as BMI makes no allowances for muscle and fat proportion in the calculation. Arnold Schwarzenagger has a BMI of 33, but his body fat is not high!
4. BMI gets the logic wrong although our own CDC says it is a reliable indicator in body fatness.
5. BMI only calculations are bad statistics as it assumes low muscle mass. All the technologies from calipers, to bio-impedance , to DXA do give you data on fat mass and therefor lean body mass, but they do not have interchangeable data. DXA measurements are most consistent, and the most accurate. At WHP Health we do Body Composition studies.
6. BMI confuses by scientific authority as most people do not know it is not measuring their fatness. Just measuring the waist is more predictive of heart health than measuring the BMI. For every two inches gained in the waist it raises your heart disease risk by 10%.
7. BMI wrongly suggests there are distinct categories of underweight, ideal, overweight and obese, with sharp boundaries that hinge on a decimal place, but it’s really more gradual than that. Feel proud if you even lose a very small amount of weight (fat).
8. Continued reliance on the BMI means doctors don't feel the need to use one of the more scientifically sound methods that are available to measure obesity levels. Even going farther would be to measure some of the abnormal substances made by the visceral fat.
9. BMI is a reasonable measure of trends, as your height won’t change, and you don’t really know if you are adding muscle or fat other than guessing based on fit of clothing and caliper pinching!
10. BMI testing should be replaced by a combination of weight, body composition and waist measurement! And that’s what we recommend for our dieters!