Obesity happens when the calories a person takes in are greater than the calories burned through activity and body functions.
Obesity is a body mass index (BMI) of 30 kg/m² or greater in an adult. BMI is a person's weight in kilograms divided by the square of their height in meters. Morbid obesity is a BMI that is higher than 40.
Since children are still growing, BMI is a percentile of a child's weight and height when compared to other children who are their gender and age. Obesity in children is a BMI in the 95th percentile or higher. Severe obesity is when it is in the120th percentile or higher.
Health Problems from Being Obese
Without treatment, obesity can raise the risk of serious health problems, such as:
- Heart disease, such as coronary artery disease (CAD) and stroke
- Type 2 diabetes
- Some types of cancer, such as liver, kidney, thyroid, colon, and rectal
- Gastrointestinal diseases, such as gastroesophageal reflux disease (GERD), gallstones, and liver disease
- Sleep apnea
- Joint problems and back pain
- Problems during pregnancy, such as high blood pressure and blood clots
Endocrine Society clinical practice guideline on pharmacological management of obesity can be found in J Clin Endocrinol Metab 2015 Feb;100(2):342.
Obesity. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/nutritional-disorders/obesity-and-the-metabolic-syndrome/obesity. Updated January 2020. Accessed January 31, 2020.
Obesity in adults. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/obesity-in-adults . Updated November 30, 2018. Accessed January 31, 2020.
Obesity in children and adolescents. EBSCO DynaMed website. https://www.dynamed.com/condition/obesity-in-children-and-adolescents . Updated October 30, 2019. Accessed January 31, 2020.
Treatment. National Heart, Lung, and Blood Institute website. Available at: https://www.nhlbi.nih.gov/health/health-topics/topics/obe/treatment. Accessed January 31, 2020.
- Reviewer: EBSCO Medical Review Board Daniel A. Ostrovsky, MD
- Review Date: 11/2019
- Update Date: 02/03/2020