Final answer:
The interpretation of BMI for children is age and sex specific, contrasting with adults, where BMI is uniformly applied regardless of these factors. Children's BMI percentiles are used to account for their growth and development.
Step-by-step explanation:
The interpretation of Body Mass Index (BMI) for children and adolescents is both age and sex specific. This differs from adults, where BMI categorizations are applied uniformly regardless of age and sex. For children, BMI percentiles are used because their bodies are growing and developing, which impacts body composition. Obesity in children is generally defined by comparing a child's BMI with reference values considering the child's age and sex. If a child's BMI is greater than the 95th percentile for children of the same age and sex, they are classified as obese. These reference values are based on large samples of children to ensure accuracy and relevance.
On the other hand, in adults, standard BMI categories apply: a BMI below 18.5 is generally considered underweight, a BMI from 18-24.9 is considered normal weight, a BMI from 25-29.9 is overweight, and a BMI of 30 or more indicates obesity. For severe obesity, also known as morbidly obese, an adult must have a BMI of 40 or more.