I made yogurt, and it was runny, so I drained it, and now I have a lot of whey. I know that it contains some of the protein from milk, but what about the other things in milk, like calcium or Vitamin A/D? Is whey nutritionally valuable, or just a waste-product?
ETA: I have Googled this, but I need some context for the answers I’m reading. How does whey compare to milk, or water, or eggs or whatever?