Body mass index or BMI is based on the weight and the height of a person. The number is often used to measure body fat and has been used for several years. But now, experts – particularly the researchers from the University of Pennsylvania’s Perelman School of Medicine – are saying it is inaccurate mainly because it does not take into account several other factors that affect the body fat content of a person such as:
- Muscle mass
- Overall body composition
- Bone density
According to the BMI chart, the normal weight is from 18.5 to 25 and you are overweight if you’re 26 to 30. Obese people are said to have a BMI of 30 and up. Many people use the BMI chart to help them determine whether they are obese or not since obesity increases the risk of several health issues, including cancer, heart diseases, and sleep apnea among others.
Calculating the BMI is easy these days. There are tools online as well as in handheld devices that allow you to get your accurate number in which you only have to input your height and weight. Recent surveys, including the report from Trust for America’s Health showed how almost two-thirds of the population in the states has high obesity rates of more than 25%. But other experts are suggesting to take those findings with a grain of salt. This is because the calculation in these surveys is simply based on the body mass.
There are a few other reasons why you shouldn’t rely on the BMI chart to tell you exactly whether you’re healthy or not and whether your weight is more than the ideal for your height. These reasons include:
- Lambert Adolphe Jacques Quetelet, the inventor of BMI explicitly said it shouldn’t be used to measure the fatness level. He wasn’t a physician, but a mathematician who introduced BMI in the early 19th
- High BMI doesn’t mean a person is overweight or even obese, but could actually mean a person is healthy and fit with just a little bit of fat.
- During the time when BMI was introduced, most people had a sedentary lifestyle and therefore the formula assumes individuals had low muscle mass with high fat content. Therefore, BMI works well on people who aren’t particularly active, but it doesn’t provide the right answer for those who are already lean, healthy, and fit.
Instead of taking the height and weight of a person, some studies emphasized that the waistline circumference should be taken into account as well, particularly in determining the risk of breast cancer, type 2 diabetes, and other diseases.