Scientists continue to confirm, there’s more to nutrition than just the classic vitamins and minerals. As important as these nutrients are to optimal health, we’re also learning that phytonutrients, enzymes, trace minerals and others play equally important roles. Original Formula IV®, developed in the 1950s, was the first multifactor food supplement to provide vitamins, minerals, enzymes, and phytonutrients, such as important lipids and sterols. Formula IV Plus carries forward this tradition of nutritional excellence with an Iron Free formulation that also provides additional mineral support, including 100% of the RDI for zinc.