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Body Mass Index

A doctor carefully listening to a patient

Body Mass Index (BMI) is a measurement used by most doctors to discuss weight. The formula takes into consideration weight and height. BMI increases with weight for the same height, and decreases with height if weight is kept the same. Using this scale, having a BMI below 18.5 is considered underweight, and having a BMI over 25 would be considered overweight or obese.

BMI was created in the early 1800s by a Belgian mathematician named, Lambert Adolphe Jacques Quetelet. The formular created does not take into consideration the relative proportions of bone, muscle, and fat. This means that a person with a large proportion of muscle could be considered overweight even though they are active and healthy.

Additionally, Quetelet created this equation by studying 9,000 white men, women, and children. It has been found that for Asian and African American people that BMI is not an accurate measurement of body fat, or even health. Typically, people who are Black or African American will have lower body fat % compared to people who are white at the same BMI. This means that a Black person with a BMI of 25 will have less fat than a white person with a BMI of 25. Additionally, Asian people tend to have a higher body fat % compared to white people at the same BMI.

If you’re doctor brings up your BMI calculation when making recommendations about weight, it is important to make sure your doctor has also taken the previous adjustments into consideration. It may also be helpful to suggest discussing Basal Metabolic Rate (BMR). BMR is a measurement of the energy your body uses, in calories, when you are at rest. This can be used to make recommendations for the number of calories you should be consuming in burning in order to maintain a healthy weight.

Use the table below to calculate you BMR:


Your calculated BMR is:

You can calculate your BMI here:

The calculated BMI is:

(Very low body fat)

(Low body fat)

(Medium body fat)

(High body fat)

(Very high body fat)

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