The Daily Value (DV) percentages on a label reflect recommended daily consumption levels established by the FDA, which are based on a 2,000-calorie-a-day diet. But even if you eat more or less calories, Lanzano says, you can use the percentages of DVs on the label to help you calculate whether a food is high or low in a particular nutrient—good or bad—such as total fat, saturated fat, cholesterol, sodium, total carbohydrates, fiber, vitamins A and C, calcium, and iron. A 5 percent DV or less is low, and 20 percent DV or more is high. The DVs for fat, cholesterol, and sodium are upper daily limits. The DV for carbohydrates and fiber are lower daily suggestions. The DVs for vitamin A, vitamin C, calcium, and iron are exact recommendations. Use the following guide to distinguish DVs from other abbreviations you might see on supplements.

Recommended Dietary Allowances (RDA). The Institute of Medicine, part of the nonprofit National Academy of Sciences, sets the RDAs, the <i>minimum</i> amounts of nutrients you need every day.

Daily Reference Intake (DRI). Starting in 1997, the Institute of Medicine included more information under the umbrella of DRIs. You’ll see each of the following on labels: estimated average requirement (EAR), recommended dietary allowance (RDA), adequate intake (AI), and tolerable upper intake level (UL).

United States Recommended Daily Allowance (USRDA). Set by the FDA, these are simplified versions of the other RDAs. This standard is being phased out in favor of RDIs.

Reference Daily Intake (RDI). The RDIs will replace the USRDA on all food and supplement labels. The numbers are pretty much the same as the old USRDAs.

Daily Recommended Value (DRV). The FDA created this standard to accommodate nutrients not covered in the RDIs. DRVs are based on a diet that contains 2,000 calories.

Sources: The Complete Idiot’s Guide to Vitamins & Minerals by Alan H. Pressman, DC, PhD, CCN (Alpha, 2007); National Institutes of Health.