Q. How do you calculate the fat percentage of a food based on the information given on the Nutrition Facts label? For example, if I want to choose a deli meat that is at least 98% fat free, how do I figure that out?
A. I think I can answer this without having to call in the opens in a new windowMath Dude! To calculate the fat percentage, you could simply divide the number of fat grams by the serving size grams. Let’s take this Nutrition Facts label from some roasted turkey as an example. A serving is 28 grams and it contains 1 g of fat. Divide 1 by 28 to get 0.03. The meat is 3% fat–or 97% fat-free.
Manufacturers usually round the numbers on the Nutrition Facts label to the nearest whole number. For example, a food with 0.6 g of fat per serving and another one with 1.4 g of fat per serving will both list 1 g of fat per serving on the label. So the true fat percentage of our turkey could be anywhere from 2% to 5%.
If you want to be a more precise, you’ll have to do an extra calculation. Divide the Calories from Fat by 9 and then divide the result by the serving size grams. In this case, 5 divided by 9 = 0.55 , divided by 28 = 0.02. This particular turkey is actually only 2% fat.
Finally, keep in mind that the fat percentage of foods is based on weight and not calories. Even though our turkey is 98% fat-free, that 2% fat accounts for about 18% of the calories in the turkey. That’s not necessarily a problem! (I’m not a fan of low-fat diets, anyway.) I point it out simply because it confuses a lot of people!