Final answer:
The standard used for daily nutrient needs of half the population is the Estimated Average Requirement (EAR), not the Recommended Dietary Allowance (RDA), which is for nearly the entire population.
Step-by-step explanation:
The standard used to estimate the daily nutrient needs of half of all individuals is the Estimated Average Requirement (EAR).
The EAR is a part of Dietary Reference Intakes (DRIs) and is set to meet the requirements for 50% of the population, which is essentially the median requirement. On the other hand, the Recommended Dietary Allowance (RDA) relies on the EAR and is used to assess the quality of people's diets, aiming to meet the needs of 97.5% of the population. The RDA can only be calculated after establishing the EAR, which requires sound research evidence. The Tolerable Upper Intake Level (UL) refers to the maximum amount of a nutrient that is unlikely to cause adverse health effects, while the Adequate Intake (AI) is used when there's not enough information to establish an EAR or RDA.
Nutrition professionals use these measures to ensure consumers maintain a balanced diet, prevent chronic diseases, and have adequate daily nutrient intake. The DRIs and MyPlate guidelines help to inform both the public and professionals about the importance of dietary balance, adequacy, and nutrient needs.