What Does BMI Mean? Using the Measurement to Address Obesity Concerns

Obesity continues to be one of our nation's largest public health concerns, and chances are that you or someone in your life struggles with obesity and the health problems commonly associated with it. But what is the science behind obesity, and what does BMI mean in relation to it? Which tools are used to diagnose obesity, and which are most effective?

Why Obesity Is a Health Concern

Obesity is a term used to describe an excessive amount of body fat. The additional weight increases your risk for metabolic disorders such as high blood pressure, high cholesterol, insulin resistance and diabetes, cardiovascular diseases, and stroke. Obesity also strains all major organ systems, further putting you at risk for other chronic or fatal diseases.

Body Mass Index (BMI)

Obesity is most commonly diagnosed using the measurement of body mass index (BMI). But what does BMI mean? It's easiest to understand it by learning how it's calculated. BMI is calculated with an equation that uses your height and weight to give you a number that can range from less than 16 to greater than 60. A healthy BMI is within the range of 18.5 to 24.9, while a BMI between 25 and 30 is considered overweight -- and anything beyond 30 is considered obese. Those reference ranges have been established based on generalized health outcomes of individuals within those different categories.

However, BMI is not always an accurate indicator of obesity. BMI doesn't take into account muscle mass, for example, so very muscular people may have a BMI indicating obesity. Only a physician or qualified health care provider can accurately diagnose obesity.

Other Diagnostic Tools

A physician or health care provider may use different methods to determine the weight status of patients. These tools include

• Waist circumference. Abdominal obesity has been linked to increased risk for coronary artery disease and type 2 diabetes, so health care professionals may measure waist circumference to determine whether you are at risk. Risk for those diseases is often associated with a waist circumference greater than 35 inches for women and 40 inches for men.
• Waist-to-hip ratio. Similar to waist circumference, a waist-to-hip ratio helps health care professionals determine your risk for heart disease and other ailments related to obesity. A ratio greater than .8 puts women at higher risk; the same goes for a ratio greater than .9 for men.
• Clinical tools. Tools such as skinfold-thickness tests and ultrasound are other accurate ways to evaluate body composition and diagnose obesity.

Ways to Reach and Maintain a Healthy Weight

Some simple strategies to get on track to achieve a healthy weight include

• Balanced eating (ensure all snacks and meals consist of 50 percent fruits and veggies, 25 percent lean proteins, and 25 percent whole grains or starchy vegetables)
• Mindful eating
• Enjoyable physical activity
• A support system

Obesity is a common but complex health problem that many of us face. By understanding the risks involved with the disease and how it's diagnosed, we can start to take steps to combat it and lead a healthier life.