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BMI and Waist Circumference: What They Mean and Why They’re Important

a person measures their waist with measuring tape

Although most people have an idea of the weight they would like to be, it’s important to know that weight isn’t just a desired number on a scale. Being at a healthy weight depends on a variety of factors, and the ideal weight differs from person to person.
That is why healthcare providers often look at two other measurements to determine whether a person has excess body fat: Body Mass Index (BMI) and Waist Circumference.

What is BMI and How is it Determined?

Body Mass Index (or BMI) is a measure of body mass based on a ratio of your weight in relation to your height. To calculate your BMI, the Center for Disease Control created the following formula: [weight (lb) / height (in) / height (in)] x 703.
A BMI between 18.5 and 24.9 is considered healthy. BMI above 25 puts you at risk for increased complications associated with type 2 diabetes – like high blood pressure, heart disease, and more. And the further above 25, the higher the risk.
However, most health experts agree that BMI is not a perfect measure. It does not account for proportion or distribution of fat or proportion of muscle mass, and people who carry their fat around their midsection have a higher risk of health complications.

What is Waist Circumference? How is it Measured?

Healthcare providers use waist circumference to measure body fat carried at the waist. Waist size is a good indicator of a person’s health risks because fat that collects around the mid-section can be harmful for the heart, liver and kidneys.
The CDC notes that a man with a waist size of 40 inches or above, or a woman with a waist size of 35 inches or above has a higher risk of type 2 diabetes, high blood pressure and coronary artery disease.
To measure your waist circumference, follow the CDC’s steps below:

  1. Stand and place a tape measure around your middle, just above your hipbones
  2. Make sure tape is horizontal around the waist
  3. Keep the tape snug around the waist, but not compressing the skin
  4. Measure your waist just after you breathe out

Men with a waist size above 40 inches and women with one above 35 inches, even if their BMI is in a healthy range, could likely still benefit from losing body fat. If you have a BMI above 25 AND a rounder belly, the case for weight loss is especially clear.

Why It’s Important to Watch Your Body Fat

In addition to the risk of health complications mentioned previously, excess body fat is one of the main contributors to insulin resistance, which leads to excess glucose in the blood.
Weight loss can result in remarkable health gains – from increased energy to decreasing medications. Even losing a moderate amount of weight can make a huge impact on improving your body’s ability to use insulin, which improves its natural ability to regulate your glucose level.
Do you want to learn more about decreasing your BMI and waist circumference? Chat with your Level2 care team about weight loss strategies.