Knowing how to read labels is really helpful to determining the value of a packaged food. To find out how much of a food is fat we can look at the calories per serving and compare it to the calories from fat per serving (which shouldn’t be more than 20%). Then we can know whether or not we should use that product.
I looked at the nutrition label on a carton of 2% milk which we would assume has 2% fat content. It turns out that a one cup serving will give you 130 calories with 45 of those calories coming from fat. Well… if I remember how to figure percentages, 2% of 130 would be less than 3 calories (2.6). Hmmm… if we divide 45 by 130 we get 35%. On my… that’s a lot more than 2% fat. How does this happen?
As it turns out, the fat in dairy products are calculated as a percentage of volume instead of a percentage of calories. That means our rule still stands… “Don’t believe what you see on the front of a package”. If you add water to the milk (which adds volume but no calories) you could have even less fat by volume. That’s why we need to know the fat content by calories. You must look at the nutrition label to determine fat content, sodium content and then read the ingredient list well.