Body Mass Index (BMI) is a number calculated from a person's weight and height. BMI is used to estimate your total amount of fat. It is designed for men and women over the age of 18.
BMI Classifications
Underweight - BMI under 18.5
Normal weight - BMI 18.5 - 24.9
Overweight - BMI 25 - 29.9
Obese - BMI of 30 or greater
For the majority of people, Body Mass Index is a reliable way to check whether your weight is putting your health at risk. However, BMI is not accurate for:
- athletes or body builders (muscle weighs more than fat, which can mean that someone very muscular can be categorised as overweight or obese)
- pregnant women
- breastfeeding women
- children
- frail older people
- people under 152cm (5 ft) tall
