 And Dr. Mangus, why don't we start here by talking about, you know, why is this deficiency such an epidemic, despite all of the awareness and the products that you see on the store shelves containing vitamin D? Well, yeah, that's a good point. 70% of us in this country are deficient in vitamin D. The fact is, is that your body needs vitamin D. This is a hormone that should be there, and it's not there.