Correct Option
The correct option is 2 only
Explanation
Body Mass Index (BMI) is a widely used anthropometric index of weight-for-height. It serves as a primary screening tool to classify underweight, overweight, and obesity in populations.
Statement-wise Analysis
- Statement 1 is Incorrect: BMI is calculated by dividing a person's weight in kilograms by the square of their height in meters ($kg/m^2$). This formula provides a standardized metric to assess body mass irrespective of frame size.
- Statement 2 is Correct: BMI is a measure of nutritional status and body composition. It is unrelated to the Intelligence Quotient (IQ), which assesses cognitive abilities and intellectual potential.
- Statement 3 is Incorrect: BMI is not exclusively used for children under the age of 5. It is the standard international metric for assessing nutritional status in adults (18 years and older). While BMI-for-age charts are used for children and adolescents (5 to 19 years), other indicators like weight-for-height are often preferred for children under 5. The claim of exclusivity to children under 5 is factually wrong.
Key Takeaway
Key Takeaway: Body Mass Index (BMI) = Weight (kg) / Height² ($m^2$). It is the standard diagnostic tool for categorizing adult nutritional status into underweight, normal range, overweight, and obese.