The Nutrition Facts food label provides information on calories, fat, carbohydrate and protein in a serving of food.

The amount of the three nutrients — fat, carbohydrate and protein — measured in grams results in the calories per serving. Each gram of fat equals 9 calories.

Carbohydrate and protein have 4 calories per gram. Nutrition Facts labels also have listings for some major vitamins and minerals. Generally, you want to have a high amount of these nutrients.

One mineral that most people are concerned about getting too much of is sodium. The percent daily value (%DV) for sodium should be less than 2,400 milligrams (mg). People who are salt-sensitive (people with high blood pressure and middle-aged and older adults) should limit daily sodium intake to 1,500 mg or less. On the Nutrition Facts label the sodium content level of a serving of food will be listed in milligrams and on the far right of that line is the "%DV" meaning that the milligrams listed is what percent of the daily value of 2,400 mg. A DV of 20 percent for sodium indicates that the food is high in salt (sodium). In the course of a day, if you add up the amount of sodium in all the foods you eat, it should be 2,400 mg or less and the %DV should add up to 100% or less. If you are on a sodium-restricted diet (1,500 mg or less) your total sodium for %DV is roughly 60% because 1,500 is approximately 60% of 2,400.

If you eat out a lot or tend to eat high-sodium snack foods or processed foods, you should practice extra caution with your other food choices. Aim to fill the majority of your diet with naturally low-sodium vegetables, fruits and unprocessed grains. Also note that the nutrient content percentages on food labels apply to the designated serving size. If you eat a larger portion than what is listed, you can quickly increase your sodium intake.

Another area of confusion on a Nutrition Facts label is the section that lists the grams of sugar in a serving of food.

You will notice that "sugars" is listed under total carbohydrate. Sugars are carbohydrate. Sugars can be natural like lactose found in milk and fructose which is naturally found in fruits.

The sugars also include table sugar, honey, molasses, corn syrup, maple syrup and others. In the case of sugar, a measured teaspoon weighs about 4 grams. So, if a label says a food contains 12 grams of sugar, that's equal to about three teaspoons. A healthy diet will always include some sugar, as it naturally occurs in many nutritious foods.

Eating too many foods with added sugars supplies calories without nutrients, makes weight control difficult.

People often ask, "Why don't the amounts for different types of fat listed on the Nutrition Facts food label add up to equal the amount listed for 'total fat'?" The numbers for individual types of fats don't always add up to the total fat figure because, in addition to those that are listed — saturated, polyunsaturated, monounsaturated — others are not. Trans fat, which is unsaturated fat whose chemical structure has changed during a fathardening process called "hydrogenation" will be listed separately on all labels in the future, but it is already figured in the total.

Total fat also includes a substance called "glycerol," which is a kind of building block for fats that does not act like a fat at all. You should also know that the numbers on food labels are rounded off. Figures rounded slightly up or down can affect the total.

How can we use the Nutrition Facts food label to choose a healthy cereal?

First, look for a whole-grain choice. The phrases on the box fronts can be misleading, so check the list of ingredients: The first item should be a whole grain such as whole wheat or oats. Second, check the Nutrition Facts panel and choose a cereal with at least three grams of fiber per serving, more if possible. Most Americans get only about half of the recommended amount of dietary fiber. If you have high blood cholesterol, you might look for brands that supply more soluble fiber through the addition of oats, psyllium, or other ingredients. If you're devoted to a lowfiber favorite, try combining it with a higher-fiber bran or whole-grain choice. Third, evaluate the sugar content. Some high-fiber cereals are very low in sugar, while others contain quite a bit more. If you intend to satisfy your sweet tooth with other foods during the day, cut back on the amount of sugar in your breakfast cereal.

But remember that part of the sugar content listed for cereals with raisins and other fruit is natural sugar in the fruit. Fourth, if you need more calcium, vitamin B-12, folate, or other nutrients, you may want a fortified cereal. However, if you eat other nutritious foods throughout the day, your cereal doesn't need to have every possible vitamin. Finally, check the fat and calorie content of your choices. If you're watching your weight, avoid cereals that pack a highcalorie content in a small portion size.

Remember the Nutrition Facts food label provides a window to compare various nutrients components in food products. The nutritional values are for a serving of that particular food. Studies show that many times we eat servings (portions) of a food that are larger than the analyzed portion. So, if you eat two servings of the food, you get twice as many calories — fat, carbohydrate, protein, etc. So read the Nutrition Facts label and know how much you are eating.