Why is the number on the scale a very limited indicator of health?

The number on the scale only tells you your weight, and while weight compared with height (your body mass index or BMI) can be an indicator of risk factors for certain weight-related diseases, it’s only one measure of many necessary to determine your overall health.

Furthermore you may be classified as overweight based on your height and weight (BMI), thus shown “at risk” for disease, but if you are a muscular exerciser with low body fat, weight means very little by itself to your health. So as long as your body fat is in the healthy range shown below, weight or BMI would generally be a non-factor in defining your health. Additionally only a complete physical examination can determine your overall health. Another tool that may be of interest to you in preserving your health throughout life is waist circumference (waist-to-hip ratio can be a measurement of abdominal fat distribution). This, along with BMI, has been shown to correlate strongly with health risks (e.g. heart and metabolic disease). Click Assessing your Risk <> from the National Heart, Lung and Blood Institute for more information. And finally, we always prefer using a body fat measurement for assessing health risk related to weight but it’s not always practical, which is why other measurements are more commonly used.

Body Fat Percentage Ranges:            

Physical Condition *


  • Very Lean < 11
  • Lean 11 – 14
  • Desirable 15 – 17
  • Average 18 – 22
  • Typical Unhealthy > 22


  • Very Lean < 19
  • Lean 19-22
  • Desirable 23-27
  • Average 28-35
  • Typical Unhealthy > 35
 * Studies reveal that the typical female college athlete has from 18 to 22 percent body fat and the typical male college athlete has 14 - 17 percent body fat (11).

The weight scale is an important measurement tool to record your body weight, but it’s limited to only body weight and no real health indicator. The numbers on the scale cannot measure your other health indicators such as: body fat/lean muscle ratio, blood pressure, hip to waist ratio or belly size, exercising heart rate and resting heart rate.

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
Most of us assume that you have to be as skinny as a coaxial cable to be healthy, but the truth is that plenty of so-called thin people are less fit and less healthy than so-called heavy people. That's right: It's actually better to be fat and have few risk factors of bad health than it is to be thin and have a higher occupancy of health-related risk factors than a bungee-jumping contest.

Now, that's not to say I'm ordering a round of fried pickles for everyone. When all else is equal, carrying extra fat will more likely increase your risk of heart attacks, strokes, and diabetes.

But my point is that I want you stop thinking about pounds and pounds only; I'd rather you start thinking about the numbers that really matter—especially to your husbands, wives, children, parents, and friends. The real story of fat isn't measured by scales or wolf whistles. It's measured by your waist size. And what it does inside your blood and arteries.
YOU: On A Diet Revised Edition: The Owner's Manual for Waist Management

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YOU: On A Diet Revised Edition: The Owner's Manual for Waist Management

For the first time in our history, scientists are uncovering astounding medical evidence about dieting -- and why so many of us struggle with our weight and the size of our waists. Now researchers...

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.