V-STACK was made using our Proprietary Cellular Absorption System that has revolutionized the supplement industry and human health. When it comes to immune boosting results it's not about how much nutrients you eat, it's about how much of those nutrients actually make it into your cells. For instance, 5000 -10,000 iu’s of vitamin D3 is recommended daily if you eat it in pill form. V-STACK has 166 micrograms per serving which is equivalent to 10,000 iu’s of D3 if eaten because the super tiny particles of D3 in V-STACK go through the mucous membrane in your mouth, into the bloodstream and directly into the cell. The process to do this is expensive but you need less which allows you to STACK more types of nutrients together, make it more powerful and save money. It also simplifies the buying process because you no longer need to order from multiple places and take handfuls of pills everyday. On top of that we always use 100% naturally occurring sources from nature, not cheap acid based synthetic versions made in a laboratory. This is another BREAKTHROUGH product we are proud of that helps working people boost their immune system bigtime and defend their health!