The "R" in RDA stands for Recommended. The RDA is a guideline developed by the Institute of Medicine that provides daily intake levels of essential nutrients that are deemed adequate to meet the nutritional needs of most healthy individuals. These guidelines help consumers understand the amounts of vitamins and minerals required for optimal health. While RDAs are useful, individual needs may vary based on factors like age, gender, and activity level, necessitating personal adjustments to one's diet.