How to Read Food Labels: Serving Size and Fat Percentage

It is common for people to underestimate how much fat and how many total calories they consume and many of these problems are related to the serving sizes and the percentage of fat listed on food labels. Serving size and fat percentage sound like they should be self-explanatory, but they can be somewhat misleading.

The number of calories in a serving of food is important, but the serving size provides the most useful information for understanding how many calories you are actually eating. For instance, a package may state, "only 100 calories per serving," but it is unlikely that you will be satisfied with only eating one serving. This is especially true for chips, cookies, and other junk food, because the serving size is typically only 1 or 2 cookies or 5 to 10 chips or crackers.

Realistically, most people eat more than one serving of food at a time, especially when the food is in a large quantity or container, such as a bag of chips. When looking at a product, try to estimate how many servings you would realistically eat at one time and then figure out how many calories that adds up to. Knowing the total number of calories you consume is much more useful than simply knowing the number of calories in one serving.

In addition to the serving size and calories per serving, it is also important to know how many of those calories are from fat, particularly when the fat is unhealthy. It is common, especially with meats, to see labels advertising a product as 80% or 90% fat-free, but this number is not the important one. The labels are designed to make the food seem like it contains a low amount of fat, but this number only refers to the percentage of weight that is fat, not the percentage of calories that are from fat.

The percentage of calories from fat is the number that really matters and it is usually very different from the percentage of fat. For example, meat that is 95% fat-free can have about 40% of its calories from fat. This is because many ingredients in food, such as water and fiber, have weight but do not add calories to the food. Also, 1 gram of fat has over twice as many calories as the same weight of a carbohydrate or protein.

The good news is food labels have to include the calories from fat right by the total calories per serving in the "Nutrition Facts" box. If you want to figure out the percentage of calories from fat you just have to divide the fat calories by the total calories. You will probably be able to get an approximation of the percentage just by looking at the numbers, but some people prefer to bring a calculator to the store with them, to get the exact number.

Keep in mind that the percentage of fat does not tell you anything about how healthy or unhealthy the fat is. This is important, because if you are buying a product that contains healthy fats, such as salmon, then a high percentage of calories from fat is actually good a good thing. On the other hand, if the food is fried or had hydrogenated oils or trans-fats, then you want the lowest percentage of fat possible.

Figuring out the percentage of calories from fat will help you make choices that minimize your intake of unhealthy fats, but it is important to note that you should not try to get the minimum amount of fat possible all the time. Your body requires some fat, particularly healthy fat like omega-3 oils, to function properly and if you cut your fat intake too much, you will actually hurt your long-term health and make it more difficult to lose body fat.