BMI: healthy range and what your number means

Body mass index (BMI) is a screening measure calculated from height and weight and used in routine health checks to estimate weight-related risk. BMI indicates whether body weight is proportionate to height, with higher BMI commonly associated with overweight and obesity, central adiposity, insulin resistance, metabolic syndrome, type 2 diabetes and fatty liver disease, while a low BMI may suggest undernutrition or reduced muscle mass in the right clinical context. Because BMI relates to cardiometabolic load, it can help explain fatigue, reduced exercise tolerance and slower recovery. BMI is best interpreted alongside waist circumference, blood pressure, fasting glucose (or HbA1c) and a lipid panel to clarify body composition and underlying risk.