figure out your height and your weight. go to a health food store site. ie. www.nutritionhouse.com and there are links to figure that out. type Body Mass Index in their search box. and there you go. or even just type it in google. it asks for your height and weight, enter it to get a number between 17 adn 25 I think. and if you are under or over that BMI range than it means you're either underweight or overweight. if your BMI is within the range, you're 'healthy' or you are a healthy weight.