Your BMI score can be used to classify your weight status. But don’t take your “classification” too seriously just yet. Moderately overweight people actually live longer than those at “normal” weight (2).
And, by the way, we take issue with the concept of “normal” as determined by classifications like the BMI classifications. So while giving you some idea of where you are with your weight, don’t focus on it too much. Everyone has a different body, and there is not a “one-size-fits-all” body type. These weight classifications (i.e. “healthy weight”) is one example of the many discriminatory challenges the overweight face on a daily basis. More on this can be found on our Obesity Discrimination page.
Here are all the weight classifications for adults and what they mean for bariatric surgery…
Body Mass Index (BMI)
18.5 – 24.9
In addition to the questionable names applied to the above classes, the BMI rating system has other limitations…
“Despite its shortcomings, knowing your BMI is a decent first step in determining which health issues you could be at risk for.
It’s also an essential component of getting insurance approval for bariatric surgery.”
- It doesn’t take into account the fact that muscle weighs more than fat, so it overestimates body fat in muscular people and underestimates body fat for people with less muscle mass.
- Fat around the midsection is worse than fat that is evenly dispersed throughout the body. For example, men with a waist circumference over 40 inches and women with a waist circumference over 35 inches have a increased risk of cardiovascular disease compared to people with the same BMI but a smaller waist circumference.
- The same BMI formula is applied to both men and women despite the inherent differences in body fat between them (men’s average BMI is 27.8 while women are at 26.8). For example, women tend to have a slightly higher percentage of body fat and men tend to be slightly heavier relative to their height because of a higher relative muscle mass. Because of this, not having a formula that takes into account gender skews the results, making them less accurate.
Despite its shortcomings, knowing how to calculate your BMI is a decent first step in determining which health issues you could be at risk for. As we’ll get into below, it’s also an essential component of getting insurance approval for bariatric surgery.
In general, you should be concerned about obesity health problems if your BMI is 30 or more or if your BMI is between 25 and 29.9 and you have two or more of the following…
- Cigarette smoking
- Family history of premature heart disease
- High blood glucose (blood sugar)
- High blood pressure (hypertension)
- Low HDL-cholesterol (“good” cholesterol)
- High LDL-cholesterol (“bad” cholesterol)
- High triglycerides
- Physical inactivity (3)
Your doctor will also know how to calculate BMI and will interpret your score along with results from several other tests to diagnose your obesity class and confirm its potential health impacts. If you doubt your BMI score and would like to cross-reference it with another at-home test, see our How to Calculate Body Fat Percentage page.