Understanding BMI (Body Mass Index)
Written By: Emma Squillace
BMI is a measurement almost everyone has heard of. But do you know exactly what it means, how it’s used in medical decisions, and why it isn’t really an ideal metric? Today we’ll explain the details of BMI and how it’s used in weight loss surgery.
You don’t need to understand math to figure out your BMI, but so you know what we’re talking about when we discuss BMI with you, it’s a ratio made of your height and your weight. Technically BMI is your weight in kilograms, squared, over your height in centimeters. Plenty of people don’t know their weight in kilograms or their height in centimeters, so calculators like this make the math easy.
There is a standard set of BMI ranges that are linked to weight categories. In general, a BMI between 18.5 & 25 is considered “normal weight”. This is the goal category for many people. When a BMI is above 25 and below 30, it falls into the “overweight” category. BMIs of 30 and over are considered “obese.” Within that category of obesity, there are sublevels used by some, which include Morbid Obesity.
Morbid obesity is a particular category you’ll likely hear about if you’re researching bariatric surgery. Unlike general “obesity” which is defined strictly by BMI, morbid obesity is more complex. The first way someone can be categorized as having morbid obesity is if they have a BMI over 40. However, another person can have morbid obesity with a BMI as low as 35, if they also have a weight-related medical condition known as a comorbidity. Common comorbities we treat include type 2 diabetes, sleep apnea, high blood pressure, high cholesterol, non-fatty liver disease, and osteoarthritis. The other way to be considered morbidly obese is if you have more than 100 pounds to lose.
Health Insurance & Bariatric Surgery Coverage
Health insurance sometimes covers bariatric surgery. Generally when this coverage is approved, it’s for someone who has morbid obesity. For example, a person with a BMI of 37 and sleep apnea may have a gastric sleeve covered by their insurance. On the other hand, someone with a BMI of 39 who does not have any comorbidities may be denied coverage. Not all insurance companies cover bariatric surgery, and they have a variety of requirements. We’re happy to help you navigate the insurance process if you have any questions. Some of our patients pay for bariatric surgery on their own, if insurance won’t cover it. Additionally, patients with a lower BMI who want to lose weight may benefit from non-surgical options like a weight loss balloon, which is approved for people with a BMI as low as 30.
Problems with BMI
BMI is used commonly for several reasons. It’s easy to calculate, it’s non-invasive, and it’s got research backing up its usefulness. In general, a higher BMI is correlated with earlier death, higher risk of some cancers, infertility, high blood pressure, type 2 diabetes, and other diseases. However, most obesity experts agree that BMI is not ideal. First of all, it does not take into account fat vs muscle. Someone can have a dangerous level of fat, but if they have very low muscle, they may not have a BMI in the obese range. Similarly, someone with high muscle can have a higher weight and therefore an “obese” BMI, when they are actually healthy. There are also BMI differences across genders, age groups, and ethnicities. For now, BMI is an accepted and easy measure of extra weight that is used by doctors, insurance companies, and the government.
BMI is a measure used regularly, but at West Medical our weight loss experts can give you a much more detailed profile of your weight, health, and medical risk. If you’re interested in learning more about bariatric surgery, we’d be happy to meet with you and explain how our process works. Please call us with any questions you have about BMI or weight loss treatments including surgical and non-surgical options. We can be reached at (855) 690-0565.