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What BMI level is considered severe or morbid obesity?
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obesity
The excessive accumulation of body fat can cause serious medical conditions.
In the context of medical definitions, severe or morbid obesity is clinically defined as having a body mass index (BMI) of 40.0 or higher.12
While BMI is a widely used standard for assessing weight status in adults over age 20, it is important to note that it serves as an estimate of total body fat rather than a direct measurement. Because the index does not account for variations in muscle mass, bone density, or body composition, health organizationsāincluding the American Medical Associationāhave cautioned against relying solely on BMI to determine an individual's overall health.12