January 21, 2022 by John Fernandez
Your BMI and What to Make of It: Your Weight and Your Health
Weight management has become even more important in the era of COVID-19, as studies have indicated that obesity, or just being overweight, can put a person at greater risk of severe coronavirus symptoms.
Knowing your proper weight is tied to a person’s BMI, or “body mass index.” BMI has gained prominence in the national conversation about ideal weight and how it ties into overall health. But many people don’t fully understand how BMI is calculated.
A BMI of 18.5-24.9 is considered the “normal” range for weight, while a calculation between 25 to 29.9 is considered overweight. And a 30 BMI or higher is considered “obese.”
“You can’t use absolute weight as a criteria (for obesity or being overweight),” explains Rachel Vallejo, M.D., a family medicine physician at Homestead Hospital. “You need to look at a person’s height and their weight together, and we call this measurement the BMI. So, 200 pounds on someone that is 6-foot-5 tall might be okay, but that weight on someone that’s 5-foot-8 would not be okay.”
A BMI is a person’s weight in kilograms divided by the square of height in meters. BMI does not measure body fat directly, but research has shown that BMI is moderately correlated with more direct measures of body fat obtained through more precise testing, according to the U.S. Centers for Disease Control and Prevention (CDC). Body fat can be determined by skinfold thickness measurements, bioelectrical impedance analysis (BIA), densitometry (underwater weighing), dual energy x-ray absorptiometry (DXA) and other methods.
A BMI often serves as a starting point, since a healthy weight is not just about one measurement. If you fall under the overweight or obese BMI categories, your doctor will likely conduct more in-depth testing, which takes into account any other underlying health numbers, including those tied to blood pressure, cholesterol and blood sugar.
BMI is inexpensive and easy to use, and it establishes a reliable weight category for physicians, dietitians and physical trainers who assist individuals in weight management and reducing risk factors for heart disease and other common conditions.
Dr. Vallejo stresses that patients need to establish a good rapport with their doctors and support staff and commit themselves to lifestyle changes to avoid chronic disease tied to being overweight or obese.
“You have to be willing and able to accept whatever the results … that there might be a risk for diabetes, or high cholesterol or heart disease, or high blood pressure … and be willing to want to make a change,” she says.
Individuals who are overweight and obese are at increased risk for many diseases, including the following listed by the CDC:
- Dyslipidemia (for example, high LDL cholesterol, low HDL cholesterol, or high levels of triglycerides)
- Type 2 diabetes
- Coronary heart disease
- Gallbladder disease
- Sleep apnea and respiratory problems
“As a physician, I feel that the accountability portion is really important, and that includes coming in for those follow-up visits and not cancelling your appointment because you’re afraid that you didn’t meet your goal,” says Dr. Vallejo. “Being accountable is about allowing us to support you and to remind you to stay on the right track. That’s all very important.”
To calculate your BMI, the CDC offers a calculator.