Recommended Dietary Allowance (RDA) is the amount of a certain nutrient you should get each day based on your age, gender, and whether you are pregnant or breastfeeding . On a supplement label, you're more likely to see the acronym DV, which stands for Daily Value. This represents how much of a nutrient the supplement provides in regards to a total daily diet. For example, if a calcium supplement is labeled "50% DV," it contains 500 mg of calcium per serving, because the DV for calcium is 1,000 mg per day. Sometimes the DV contained in a supplement will be higher than the RDA for certain people. In many cases, there is no DV for a supplement, so the label will reflect that. Check with your doctor to make sure your supplement doesn't contain too much of any nutrient.