Body mass index (BMI) is a measure of body fat based on height and weight. It is used to screen for weight-related health problems such as obesity, heart disease, stroke, type 2 diabetes, and some types of cancer. BMI is calculated using the following formula: weight (kg) / height (m2). For women, BMI is classified as follows: underweight (<18.5), normal weight (18.5-24.9), overweight (25-29.9), and obese (30 or greater).
BMI is a useful tool for screening for weight-related health problems, but it is important to note that it is not a perfect measure of body fat. For example, athletes may have a high BMI due to their increased muscle mass. Additionally, BMI does not take into account body fat distribution. People who carry their weight around their waist are at greater risk for health problems than those who carry their weight around their hips and thighs.