BMI
Quick Definition
Body Mass Index -- a measure of body fat based on height and weight that applies to adult men and women.
In-Depth Explanation
Body Mass Index (BMI) is calculated by dividing a person's weight in kilograms by the square of their height in meters (kg/m2). It was devised in the 1830s by Belgian mathematician Adolphe Quetelet.
BMI categories for adults are: underweight (below 18.5), normal weight (18.5-24.9), overweight (25-29.9), and obese (30 and above). While widely used in clinical settings and population health studies, BMI has significant limitations.
It does not distinguish between muscle and fat mass, does not account for fat distribution, and may not be equally accurate across different ethnic groups, ages, and sexes. Many health professionals now recommend using BMI alongside other measures like waist circumference, body fat percentage, and metabolic health markers.