% DV
The % Daily Values (%DVs) are based on the Daily Value recommendations for key nutrients but only for a 2,000 calorie daily diet-not 2,500 calories. You, like most people, may not know how many calories you consume in a day. But you can still use the %DV as a frame of reference whether or not you consume more or less than 2,000 calories.
The %DV helps you determine if a serving of food is high or low in a nutrient. Note: a few nutrients, like trans fat, do not have a %DV.
Do you need to know how to calculate percentages to use the %DV? No, the label (the %DV) does the math for you. It helps you interpret the numbers (grams and milligrams) by putting them all on the same scale for the day (0-100%DV). The %DV column doesn’t add up vertically to 100%. Instead each nutrient is based on 100% of the daily requirements for that nutrient (for a 2,000 calorie diet). This way you can tell high from low and know which nutrients contribute a lot, or a little, to your daily recommended allowance (upper or lower).
The %DV also makes it easy for you to make comparisons. You can compare one product or brand to a similar product. Just make sure the serving sizes are similar, especially the weight (e.g. gram, milligram, ounces) of each product. It’s easy to see which foods are higher or lower in nutrients because the serving sizes are generally consistent for similar types of foods, except in a few cases like cereals.
Use the %DV to help you quickly distinguish one claim from another, such as “reduced fat” vs. “light” or “nonfat.” Just compare the %DVs for Total Fat in each food product to see which one is higher or lower in that nutrient–there is no need to memorize definitions. This works when comparing all nutrient content claims, e.g., less, light, low, free, more, high, etc.
You can use the %DV to help you make dietary trade-offs with other foods throughout the day. You don’t have to give up a favorite food to eat a healthy diet. When a food you like is high in fat, balance it with foods that are low in fat at other times of the day. Also, pay attention to how much you eat so that the total amount of fat for the day stays below 100%DV.
Source: http://www.fda.gov/Food/LabelingNutrition/ConsumerInformation/ucm078889.htm#see1
