How to Calculate Body Mass Index (BMI)

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The body mass index or BMI is a global parameter that is used to calculate the risk of obesity on people, as well as if there is weight gain or loss. BMI can show us if someone is with overweight, which can cause high cholesterol and high blood pressure, as well as increase the risk of coronary artery disease. Remeber that obesity represents a large percentage of cardiovascular risks like diabetes.

How is the body mass index determined?

It’s easy: Body Mass Index (or BMI) is calculated as your weight (in kilograms) divided by the square of your height (in metres) or BMI = Kg/M2. According to the U.S. National Heart, Lung, and Blood Institute, the parameters for determining whether a person is overweight or obese are these:

  • BMI less than 18.5 = Underweight
  • 18.5-24.9 BMI = Ideal Weight
  • BMI 25-30 = Overweight
  • BMI over 30 = Obesity

There may be a margin of error, for example, some people have too much muscle mass, this does not imply that they are overweight. The BMI takes into account only the weight and does not differentiate which percentage is fat and which is muscle. So you have to see a profesional if you want a precise diagnostic. Therefore, the number obtained by applying the formula is a quick estimate of the body fat of an adult person.

Because children grow steadily and at different rates, they have differences in the distribution of their body fat, within a range of normal body shapes and sizes. So, instead of using the calculated BMI number, as is in the case of adults, BMI percentiles take into account the growth and development of children to calculate if they are in the range of a healthy weight.

In children, a high amount of body fat could lead to weight-related diseases and other health issues. Being underweight can also put one at risk for health issues.

To calculate children’s BMI, a pediatrician will measure the child’s height and weight and then apply the following formula:

  • Multiply weight (in pounds by 703): 184 × 703 = (A) 129,352
  • Multiply height in inches by herself: 69 × 69 = (B) 4,761
  • Divide (A) by (B): 129,352 ÷ 4,761 = 27.2 (BMI score)

Diet is important

Obesity is a serious health problem, and that puts you at risk of short-term complications, it is important to implement a balanced diet in the family. Because obesity affects not only adults, but also children. In addition, this disease is one of the risk factors for covid-19, so it is important to know the BMI of each family member and carry out adequate weight control.