A person is obese if he has weight for height –
**Core Concept**
The concept of obesity is defined by an excess of body fat, which is typically assessed by the body mass index (BMI). BMI is calculated by dividing the person's weight in kilograms by the square of their height in meters. This is a widely used indicator to categorize individuals as underweight, normal weight, overweight, or obese.
**Why the Correct Answer is Right**
The correct formula for calculating BMI is weight in kilograms divided by the square of height in meters (kg/m^2). This allows for the accurate classification of individuals into different BMI categories, such as underweight (BMI < 18.5), normal weight (BMI = 18.5-24.9), overweight (BMI = 25-29.9), or obese (BMI ≥ 30). The World Health Organization (WHO) uses this classification system to define obesity and other weight-related health issues.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because the formula for calculating BMI is weight in kilograms divided by the square of height in meters, not just weight for height. This option lacks the necessary height component.
**Option B:** Incorrect because it is incomplete and does not provide the necessary information to calculate BMI. The formula requires both weight and height measurements.
**Option C:** Incorrect because while weight is an essential component of BMI, height is equally important and must be taken into account when calculating BMI.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that BMI is not a perfect measure, as it does not account for muscle mass or body composition. However, it remains a widely used and accepted indicator for assessing weight status and identifying potential health risks associated with obesity.
**Correct Answer: D. weight for height divided by the square of height in meters**