Final answer:
The recommended average daily nutrient intake level by a healthy person when there is not enough research to establish the RDA is known as Adequate Intake (AI). AI, alongside RDA, UL, and EER, is part of the Dietary Reference Intakes designed to optimize health and prevent nutritional issues.
The correct option is 2) adequate intake
Step-by-step explanation:
The recommended average daily nutrient intake level by a healthy person when there is not enough research to determine the full Recommended Dietary Allowance (RDA) is known as Adequate Intake (AI). AI is established based on observed or experimentally-determined estimates of nutrient intake by a group of healthy people that are assumed to be adequate. It is used when there is not enough information to set an Estimated Average Requirement (EAR), which would be needed to calculate an RDA. The AI is typically a higher level than the EAR to cover the needs of different individuals within the population.
Other terms related to daily nutrient intake levels include the Tolerable Upper Intake Level (UL), also referred to as the upper limit, which is the maximum amount of a nutrient that is considered safe to consume daily without risk of adverse health effects for most people. The RDA, which is the average daily intake level sufficient to meet the nutrient requirements of nearly all (97.5%) healthy individuals in a particular life stage and gender group, is set closer to the actual requirement for most people.
The Dietary Reference Intakes (DRIs) encompass these different measures, including RDA, AI, UL, and the Estimated Energy Requirement (EER), all providing guidance on nutrient intake to optimize health and prevent both deficiencies and excessive intake.