How to Calculate the Percentage of Body Fat Lost

Monitoring your body weight alone can be misleading and not indicative of the condition of your overall physique. Even at the same weight, someone with excessive body fat can appear overweight, while someone with low body fat can appear lean and trim. Body fat is essentially an energy storage system, which can shroud your otherwise fit body in a blanket of blubber. Therefore the goal of weight loss should focus more on reducing body fat to healthy levels, which can be 19 percent to 26 percent for women and 10 percent to 20 percent for men ages 20 to 40.

Things You'll Need

• Body fat scale

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Instructions

• 1

  Use a body fat scale to test your body fat percentage. Also check your weight. Although a body fat scale is not the most accurate, it is the easiest. The most accurate way would be a hydrostatic body fat test, which requires special facilities and can be very expensive.

• 2

  Divide the body fat percentage by 100 to convert into decimal format, and then multiply that figure by your body weight. This gives you the weight of your body fat. For example, If you weigh 180 pounds with 30 percent body fat, then you have 54 pounds of body fat.

• 3

  Repeat the test and calculation whenever you wish to test your progress, or after a lengthy training regime. As an example, if the second test comes back as 20 percent body fat at 160 pounds, then you have 32 pounds of body fat.

• 4

  Subtract the body fat weight of the second test from the initial test. In the examples given, you would have reduced your body fat by 22 pounds.

• 5

  Divide that difference by the initial body fat weight to calculate the percentage of body fat lost. In the example, 22 divided by 54 gives you a body fat reduction of 40.7 percent.

• 6

  Divide the body fat weight difference by the original body weight to convert the previous calculation into equivalent terms of body fat percentage. In the example, 22 divided by 180 tells you that you lost 12.2 percent of your body weight attributable to fat loss alone.