Body Mass Index (BMI) is a number calculated from a person's weight and height. BMI provides a reliable indicator of body fatness for most people and is used to screen for weight categories that may lead to health problems. (Source CDC.gov)
Anyone who is overweight should try to avoid gaining additional weight. Additionally, if you are overweight with other risk factors (such as high LDL cholesterol, low HDL cholesterol, or high blood pressure), you should try to lose weight. Even a small weight loss (just 10% of your current weight) may help lower the risk of disease. Talk with your healthcare provider to determine appropriate ways to lose weight. (Source CDC.gov)