1. Recommended Dietary Allowances (RDAs): The average daily intake level that meets the nutrient requirements of nearly all (97-98%) healthy individuals in a specific age and gender group. 2. Adequate Intakes (AIs): Established when there is not enough evidence to develop an RDA. AIs are based on observed or experimentally determined estimates of nutrient intake by healthy people. 3. Tolerable Upper Intake Levels (ULs): The maximum daily intake unlikely to cause adverse health effects. Exceeding ULs increases the risk of toxicity. 4. Estimated Average Requirements (EARs): The daily intake value estimated to meet the requirement of half the healthy individuals in a particular age and gender group. EARs are used to assess the nutritional adequacy of populations and to develop RDAs.
