Return to index
BODY MASS INDEX (BMI)
An indirect measure of body fat. Identifies possible weight problems for adults, and allows individuals to compare their weight status to that of the general population. BMI = weight(kg)/height(m2).
Interpretation of BMI in adults
BMI takes no account of fat distribution or body composition; for example, a highly trained athlete may have a high BMI because of increased muscularity rather than increased body fat. An alternative predictor of risk for obesity-related diseases is waist circumference.
Black, Asian and other minority ethnic groups are aware that they face an increased risk of chronic health conditions at a lower BMI than the white population (below 25 kg/m2).
BMI Calculator Patient Professional Reference/Medical calculators
NICE CG189. Obesity: identification, assessment and management; 2014. https://www.nice.org.uk/guidance/cg189
NICE PH46. BMI: preventing illhealth and premature death in black, Asian and other minority ethnicities; 2013 https://www.nice.org.uk/guidance/ph46
Interpretation of BMI in children
Specific age-adjusted and sex-specific charts must be used for children.
About BMI for children and teens US Centers for Disease Control and Prevention (CDC)
Practice Nurse featured article
Practical Skills in Primary Care: Part 1 Stephanie Garner
Practice Nurse Curriculum Module
See Obesity, Waist circumference