Obesity is an "abnormal or excessive accumulation of fat that presents a risk to health." There are several ways to measure a person's body fat percentage, including waist circumference, waist-to-hip ratio, skinfold measurements, and body mass index (BMI). Obesity increases the risk of serious health conditions like cardiovascular disease, type 2 diabetes, sleep disorders, and certain cancers. Common treatments for obesity include healthy eating and physical activity.

    Key Terms

    Frequently Asked Questions

    • Is obesity a disease?

      Yes, the American Medical Association (AMA) defines obesity as a disease that stems from a complex mixture of factors including genetics, environment, and behavior. It’s considered an epidemic in the United States, with more than a third of the population estimated to be obese.

    • What is considered obese?

      You’re generally considered obese if your body mass index (BMI) is 30 or higher. BMI is calculated by dividing your weight by your height squared. However, that number doesn’t take into consideration important factors such as muscle mass or frame size. Your doctor should consider the number in the context of your overall health when determining whether you’re obese.

    • What causes obesity?

      Obesity is caused by an energy imbalance between calories consumed and calories expended, although some people are more predisposed to obesity than others.

      Factors that contribute to obesity include:

    • How can I prevent obesity?

      Obesity is mostly preventable with a healthy lifestyle:

      • Eating a balanced, portion-controlled diet
      • Being active
      • Finding healthy outlets for stress
      • Getting enough sleep

      While this is especially important for those with a family history of obesity, medical conditions that contribute to weight gain, and other risk factors, everyone’s health can benefit from these strategies.

    Page Sources
    Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
    1. World Health Organization. WHO European Regional Obesity Report 2022

    2. Powell-Wiley TM, Poirier P, Burke LE, et al. Obesity and cardiovascular disease: A scientific statement from the American Heart Association. Circulation. 2021;143(21):e984-e1010. doi:10.1161/CIR.0000000000000973

    3. National Institute of Diabetes and Digestive Kidney Diseases. Treatment for overweight & obesity.

    4. University Health Care System. About Morbid Obesity - What is Obesity?

    5. World Health Organization. Physical Activity.

    Additional Reading