What is obesity?
There are many ways in which a person's health in relation to their weight can be classified, but the most widely used method is body mass index (BMI). BMI is a measure of whether you're a healthy weight for your height. You can use the BMI healthy weight chart to work out your score. For most adults, a BMI of: 18.5 to 24.9 means you're a healthy weight 25 to 29.9 means you're overweight 30 to 39.9 means you're obese 40 or above means you're severely obese BMI isn't used to definitively diagnose obesity, because people who are very muscular sometimes have a high BMI without excess fat. But for most people, BMI is a useful indication of whether they're a healthy weight, overweight or obese. A better measure of excess fat is waist circumference, which can be used as an additional measure in people who are overweight (with a BMI of 25 to 29.9) or moderately obese (with a BMI of 30 to 34.9). Generally, men with a waist circumference of 94cm (37in) or more and women with a waist circumference of 80cm (about 31.5in) or more are more likely to develop obesity-related health problems