While both AI and RDA serve as nutritional guidelines, they differ significantly in their derivation and application. RDA is the daily dietary intake level sufficient to meet the nutrient requirements of nearly all (97-98%) healthy individuals in a particular life stage and gender group.
Conversely, AI is employed when sufficient evidence is lacking to establish an RDA. Therefore, while RDAs are rooted in robust scientific evidence, AIs are more prudent estimations. Thus, these two facets form an integral part of the Dietary Reference Intakes (DRIs), guiding individuals towards healthful dietary practices.