How is obesity defined in terms of body-mass index?

Obesity is defined in terms of body mass index (BMI) as a BMI greater than 30. This classification is based on established guidelines from health organizations such as the World Health Organization (WHO). The BMI is a numerical value calculated from an individual's weight and height, providing a simple and widely used method for assessing whether an individual has a healthy body weight.

When the BMI is greater than 30, it indicates that an individual is likely to be at an increased risk for various health issues, including heart disease, diabetes, and certain types of cancer, among others. This definition is significant for public health initiatives aimed at addressing and preventing obesity-related health problems across populations.

The cutoffs for other BMI classifications include overweight, which is defined as a BMI greater than 25 but less than or equal to 30. While values greater than 35 and 40 indicate different levels of severe obesity, the basic definition of obesity begins at a BMI greater than 30, which is why that heightens the concern in health discussions about the risks associated with excessively high body weights.