Adding powdered milk for calcium

[Riponite]

I have read in more than one place I remember that you can add powdered milk to lots of baked things to add calcium. But - I have no idea how much milk you can replace flour with before the cake, bread etc has not enough flour and something chemical goes wrong. Does anyone have any kind of guide or ratio for doing this?

can you not just use fortified flour ? Can't imagine you'd get that much more calcium into food like this tbh.