When we were younger, doctors would measure our height and weight and assign us a number—our BMI. Even today, BMI is still used as an indicator of health among many doctors, nutritionists, and schools. However, your BMI isn’t necessarily an accurate indicator of health. Read on to find out why:
What is BMI?
BMI or Body Mass Index, is a number comprised of a person’s body weight in kilograms divided by their height in meters. This number is used mainly as a screening tool for children, teens, and young adults to determine if they are over or underweight. For example, if someone’s BMI was on the lower end, their doctor might ask about eating habits and take a closer look at their lifestyle.
The Body Mass Index is a great way for doctors to screen new patients and learn more about their lifestyles, determine risk levels for illnesses and complications like arthritis, diabetes, high blood pressure, and even some types of cancer as well. It is also an effective tool for measuring a population’s average BMI, which can determine how healthy a specific demographic is.
How can BMI be Inaccurate?
BMI, however, is not always an accurate indicator of whether or not someone is healthy. Body types, muscle mass, and age all play key roles in determining someone’s health level and if they are over or underweight.
BMI in Children
In children and the elderly, BMI isn’t always an accurate depiction of how healthy children or elderly people are because they typically have more fat in their bodies than the average adult. With children, growth spurts and losing baby fat can alter their BMI drastically even if they are still active, healthy kids.
BMI and Muscle Mass
The most common argument for the inaccuracies of the Body Mass Index is that it is standardized, meaning it doesn’t take into account muscle mass, bone structure, gender differences, and athleticism. People who have larger frames and more muscle mass (think bodybuilders) will have a much higher BMI than someone with a thin frame that doesn’t work out much. However, the bodybuilder exercises regularly and is more likely to be healthier than a sedentary person.
BMI tends to get complicated in women as well. Since it is standardized, it can be difficult for women to be placed appropriately on the Body Mass Index. People born female tend to have a lower BMI than those who are born male, so their numbers will be significantly lower than a cisgender man’s.
How is my BMI Related to My Health?
Another inaccuracy that comes with relying on BMI is that it cannot accurately determine how healthy someone is. There are many ways people with average BMIs can have increased health risks: heavy smoking, high cholesterol, high blood pressure, and heavy drinking, for example, can all play into someone’s health regardless of their weight or fitness level. BMI also does not account for the health risks that accompany eating disorders, which may alter someone’s BMI in the short-term but cause serious complications in the long run.
So should you just ignore your BMI? Yes and no. Your Body Mass Index isn’t something that should be checked every day, and best left in the hands of your primary care physician. BMI is just one small way to determine health, and alone it can be wildly inaccurate. It is always best to get the whole picture before jumping to conclusions about weight, fitness level, and other aspects of health, even for yourself!