We all have read nutrition labels at one point or another. If we are trying to eat healthier, we may read them even more. But can we trust them?

Nutrition labels are regulated by the FDA, and are required on most prepared foods, such as breads, cereals, canned and frozen foods, snacks, desserts, drinks, etc. Nutrition labeling for raw produce (fruits and vegetables) and fish is voluntary. But just how regulated are any labels? The answer to that comes in the form of a government document. A document that is difficult to maneuver, and sometimes even harder to understand. Believe me, I tried. And what is the verdict?

The nutrition labels have to be within 20% accurate to be in regulation. That means it could say the food contains 20g of fat, and it might have 24g. Or it could have 16g. And either would be just fine according to the FDA.

That isn’t very accurate. So what can we do if we are really trying to be conscious of our intake?

Besides trying to eat foods that are less processed and therefore less in need of a nutrition label, we can test the labels. Let’s start by checking the math.

* Divide the weight by the number of servings. Does it equal the serving size?

* Calculate the calories (grams of fat times 9, grams of protein and carb times 4). Does the answer match the reported calories within 10 to 20 (rounding could make the result a bit different)?

If your calculation is higher than the reported calories, and the food contains fiber, remember that manufacturers are allowed to exclude calories from insoluble fiber. So try leaving out the fiber and see if that straightens things out. If your new calculation is now lower than the reported calories, the fiber is probably a mix of insoluble and soluble. (Remember that soluble fiber must be included as 4 calories per gram.)

If there are sugar alcohols present, the manufacturer is permitted to count them as less than 4 calories per gram. There are different types of sugar alcohols, and each has a different value. However, because the least digestible ones tend to be the most laxative (if you can’t digest it, it has to go somewhere!), chances are the amount per serving is small. Count each gram as two calories and see if your new calculation is in the right ballpark.

If the numbers still don’t add up, something is wrong. You should be wary of that food, and most likely that manufacturer as well.

Be an informed, and healthy, consumer.