The BMI (Body Mass Index) is undoubtedly a widespread health indicator. The relevancy of the BMI as a good health indicator is a recurrent topic in the health and fitness industry. Many health professionals use BMI, but some experts say that it doesn’t provide an accurate picture. But what does the result of your BMI tell you? Is it accurate? Can the BMI results be trusted? We’ll explore these questions and more in this blog post!
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What Is The BMI? What Does The BMI Tell Me?
The Body Mass Index (BMI) is an approximate measure of your total body fat. The BMI tells whether you are – most likely – underweight, well-built, or overweight. The BMI indirectly tells you what your best weight for health is.
The BMI can also define an ideal healthy weight or a weight reduction goal in a diet program via a reverse BMI Calculator.
What Is The BMI Formula?
The original BMI formula is weight in kilograms (kg) divided by height in meters squared (m)² as follow:
Metric-System BMI formula: BMI = Weight (kg) / Height (m)²
As a BMI formula example, a 60kg 165cm person has a BMI of 60/(1.65)^2=22.
Please note that the original Metric-System BMI formula uses meters and not cm when taking into account height. With the Imperial system, the original BMI formula is adjusted by a factor for weight and tall conversion purposes.
Imperial-System BMI formula: BMI = 703 * Weight (lbs) / Height (inches)²
As a BMI formula example using the imperial system, a 134lbs 64inch person has a BMI of 703 * 134 / 64² = 23.
Do Doctors Still Use Bmi?
Yes, they do. Doctors use BMI to assess a patient’s risk for obesity-related diseases and conditions, such as diabetes. Medical professionals know that the Body Mass Index must be interpreted within an adjusted BMI benchmark for some ethnicities to yield good insight into an individual’s health. Further adjustments are also required when the individual is very short or very tall or has an above-average proportion of muscle bulk.
Still, some people fail to do so and draw the wrong conclusion from the BMI result. A a result, the metric has been questioned due to its lack of accuracy in some cases.
Can The BMI Be Trusted?
Yes, the BMI is a trustworthy health indicator as long as the BMI result is interpreted correctly and adjusted for context. To draw the correct conclusion from a BMI calculation, it is essential to compare the BMI result with an ethnicity-adjusted BMI benchmark. For example, a BMI of 18 would be considered unhealthy in many situations, but it is a perfectly normal BMI for an Asian woman.
How Accurate Is The Bmi Calculator?
The correct interpretation of the BMI result is the key to making the BMI a good health indicator. The accuracy of the BMI result is as good as its input data accuracy, weight, and height. This live BMI calculator uses the Body Mass Index formula straightforwardly to get your BMI result. However, the interpretation of your BMI result is subject to variation.
Is The Bmi A Good Health Indicator?
There has been much debate about the trustworthiness of BMI as an indicator for overall fitness or even weight. The truth is that the BMI calculation itself (i.e., the BMI value given by the BMI formula) is not directly a good health indicator if interpreted straightforwardly.
Still, a correct interpretation of the BMI value adjusted for context (Height, ethnicity, muscle mass..) makes the BMI a good health indicator worth tracking.
For instance, the context of the athletic lifestyle of the individual must be factored in. For example, the video below gives the example of Marshawn Lynch, a running back football player whose weight is 98kg and height is 1.8m. His BMI result is 30. A BMI of 30 would indicate that this individual is obese if interpreted out of context. It couldn’t be further from the truth.
Another example is that the BMI result interpretation must be adjusted for ethnicity, particularly when the BMI is calculated for Asian people. Find out what is the Asian healthy BMI here. Finally, women with more significant than average breasts must keep in mind that their breast size will increase the BMI value; see how breast size impacts the BMI result.
What BMI doesn’t Tell You About Your Health?
The BMI value must be adjusted for context (Height, ethnicity, muscles mass..). Indeed, the BMI may penalize you for instance, if you have a lot of muscles as your weight will climb, but not your height. The video below explains what the BMI doesn’t tell: