• What is Obesity?

    Defining Obesity

    The Centers for Disease Control and Prevention defines obesity as a range of weight that has been shown to increase the likelihood of certain diseases and conditions. These diseases are serious on their own, and when combined with obesity can cause a host of problems, including premature death.

    Determining Obesity: Body Mass Index

    Obesity is determined using a measure called body mass index (BMI). Your BMI is calculated by an equation that factors weight and height.

    A normal BMI ranges from 18.5 to 24.9. A person with a BMI of 25 to 29.9 is considered overweight. A BMI of 30 or more is considered obese, with a 40-plus BMI classified as morbidly obese. As an example, a five-foot, seven-inch adult can weigh anywhere between 118 and 159 pounds and fall within the normal range.

    It’s important to note that BMI does not measure body fat. An extremely muscular and fit person may register a high BMI and be very healthy. Although an important issue in determining whether a person is at risk for certain diseases, BMI is not the only factor considered.

    Physicians also consider the following:

    • Diet
    • Physical activity
    • Blood pressure
    • Cholesterol
    • Body fat distribution ("apple-shape" versus "pear-shape")

    View the BMI chart

    Determine your BMI with an interactive calculator