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How Nutrition Works

Reading Food Labels
©2006 Publications International An example of a nutrition label.

Healthy eating guidelines, which are supposed to help us, can be a little daunting when it comes right down to deciding what to cook for dinner tonight and what to buy at the supermarket. What ingredients you be looking for? How much is a good amount? Even selecting food -- let along preparing and eating it -- can be confusing.

But selecting food is important. Planning smart menus and shopping wisely are crucial links in the good nutrition chain. Standardized food labels can provide some guidance, as can a few calorie-cutting menu ideas and cooking techniques. But how do you know what to look for?

Food Labeling 101

Don't you hate it? You're all set to enjoy creamy, rich chocolate fudge ice cream, and there it is, staring you in the face -- the food label that tells you it has 260 calories a serving and one serving is half a cup.

But you had a cup, at least, which means you just downed 520 calories or more. Even when you have no desire to know, those "Nutrition Facts" can't be ignored. Most nutritionists think that means we've come a long way, and indeed, we have. Most of us, when we aren't splurging on ice cream, are grateful for whatever information we can get about what we eat, because we really do want to eat healthy foods.

Mandatory food labels made their debut in May 1994. Before that time, the emphasis was on vitamin content, reflecting the concern with nutrient deficiencies in the first half of the century. Now, however, we're more worried about diseases of excess, in particular heart disease and cancer. So, today's food labels reveal information about calorie and fat content, in addition to vitamins.

Labels now use the Daily Value (DV) as the standard recommended intake for key nutrients at two calorie levels: 2,000 and 2,500 calories a day. The percentage of the Daily Value (%DV) listed on the label for each nutrient shows a food's relative contribution of nutrients. Be sure to keep in mind, though, that if you consume less than 2,000 or 2,500 calories a day, your maximum daily amounts for those nutrients will be lower.

And if you consume more calories per day, as do some men and athletes, then your maximum daily amounts will be higher. In most cases (for example, vitamins, minerals, and fiber) the higher the %DV, the better. However, for fat, cholesterol, and sodium, you want a low %DV. The %DV for fat on a label refers to how much of your daily total of fat this one food contributes. A %DV of 25 means that this particular food provides one-quarter of your fat allowance for a whole day. That's a lot of fat for one food.

You can also just check out the grams of fat. It's listed in regular type right next to the boldface words Total Fat -- easy to miss unless you look for it. It tells you all you really need to know. If the label lists saturated or trans fat, you may want to avoid the food. If you want, you can also check out the number of calories from fat after Calories from Fat (on smaller packages, it may be listed as Fat Calories).

If all this is too confusing, don't worry. You don't even need to understand it, if all you want to do is compare foods. Just compare numbers, but be careful what you're comparing. Although serving sizes are supposedly standardized, the government's idea of a serving size may not be yours.

Often, it may be less. That's why you need to figure the number of calories and nutrients for the amount you actually eat. Be especially careful of diet or "light" foods -- their serving size is often twice what the regular version of the food is. For example, a serving size of regular bread is considered one slice, but light bread must use a serving size of two slices, even though you wouldn't necessarily eat any more of the light bread than regular bread.

Health Claims Become Legit

It was novel -- and even shocking to some -- when Kellogg first aired its All-Bran ads that linked a high-fiber diet with less risk of "certain types of cancer." It was groundbreaking, and not technically legal at the time, because it made a health claim for a food. However, the Food and Drug Administration (FDA) tolerated it.  More claims followed, for better or worse.

Now, there are guidelines that allow for specific health claims linking diet and disease to appear on food labels. The following pairings of nutrients with health claims are examples of those allowed on food labels:

Dietary saturated fat and cholesterol with increased risk of heart disease

  • Sodium with increased risk of high blood pressure
  • Fruits and vegetables with reduced risk of cancer
  • The fiber in fruits, vegetables, and grains with reduced risk of cancer
  • The soluble fiber in fruits, vegetables, barley, and other grains with reduced risk of heart disease
  • Calcium with reduced risk of osteoporosis
  • Plant sterol or plant stanol esters with reduced risk of heart disease
  • Sugar alcohols, such as xylitol, with reduced risk of dental caries

If the necessary information isn't there, or you don't feel like being a sleuth, check the ingredient label. If "hydrogenated" or "partially hydrogenated" fats are listed, then the product contains trans fatty acids, and the closer it is to the beginning of the list, the more there is in the food.Full Food DisclosureThere is good news for food-allergy sufferers. Companies now have to be more specific in their ingredient lists, making life easier for people who are allergic to certain ingredients and must ferret out foods containing them. For example, companies can no longer list protein hydrolysates as "flavorings." They must be listed by name, such as hydrolyzed wheat gluten or hydrolyzed casein. Color additives must also be listed by name, such as yellow dye #5 (tartrazine).Companies also must now 'fess up to the percentage of juice in their juice products. However, it's easy to be fooled if you don't check the ingredient list and nutrition label. A juice can be labeled as 100 percent juice but contain mostly "filler" juices -- white grape juice, apple juice, or pear juice -- which provide little nutrition and, in the case of apple juice, can even trigger diarrhea. Check the ingredient list to know what you're getting. Then check the nutrition facts to see what nutrients, if any, are present.One of the items you'll want to look for on a nutrition label is fat content. As we mentioned earlier, too much fat in your diet can lead to heart disease. In the next section, you will learn how to limit fat in your diet.This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.