The following body fat chart describes body fat ranges and their associated categories. It is created by the American Council on Exercise.

Body Fat Percentage Categories

ClassificationWomen (% fat)Men (% fat)
Essential Fat10-12%2-4%
Athletes14-20%6-13%
Fitness21-24%14-17%
Acceptable25-31%18-25%
Obese32%+25%+

Knowing your body fat percentage can also help you determine if your weight loss goals are realistic. Remember, weight loss doesn't always mean fat loss.

For example, let's say you are a 130 pound woman with 23% body fat, and your goal is to lose 20 pounds.

Initial body fat130 pounds x 0.23 body fat = 30 pounds body fat
Lean body mass130 pounds total - 30 pounds fat = 100 pounds lean body mass
(bones, organs,...)
Goal130 pounds - 20 pounds = 110 pounds

As you can see, the goal of losing 20 pounds is not realistic or healthy. At 110 pounds, this woman still requires 100 pounds of lean body mass, but would only be carrying 10 pounds, or only 9% body fat. From the body fat chart above, you can see that this is a dangerously low percentage.

A better goal might be for the woman to reduce her body fat from 23% to 18%. In this case:

130 pounds x 0.18 = 23 pounds body fat

100 pounds lean body mass + 23 pounds body fat = 123 pounds goal weight.

So, for this individual to achieve a lean, but healthy 18% fat, she would need to lose only 7 pounds of fat, reducing her weight from her current 130 pounds to 123 pounds. Losing more than 7 pounds means losing lean body mass (usually metabolically-active muscle tissue), which is clearly not desirable.

So before you decide that you need to "lose weight", remember to consider that "weight" consists of both lean body mass and body fat. Try to keep your weight loss goals realistic, and remember, keep the calorie-burning muscle, and lose only the fat.