Stop believing stuff on the internet (Haha Iroonnnyyyy), there are no vitamins in tap water. Vitamins are organic compounds produced biologically, you don't find them in tap water only in them in the food you eat. This myth about having to drink tap water to get your mineral content/ vitamins is unbelievably wrong.
A single 50g serving of Swiss cheese contains 480 mg of Calcium which equates to about 1.19 e-2 mols of calcium or 7,211976048000000000000 molecules (7.2e21). Calgary water has 200 ppm of dissolved minerals (Including Calcium, Magnesium, sodium...). 50 mL of water is 50g, at 200 ppm 0.02% of that is minerals or 0.01g, this means that there are about 2.49e-4 mols of minerals or 1.49e20 molecules (using the heavier weight of calcium to calculate).
What does it all mean Basil!
Well for every 1 calcium molecule in cheese there are 0.02 dissolved hardness molecules in water (again this includes Calcium, Magnesium, Sodium, Potassium...). So you would have to drink 2.5L of water to match 50g of cheese and I'm still comparing apples to oranges here as that's pure calcium in cheese and an accumulation of all hardness minerals in water.
The major advantage to drinking RO water is that you know it's ONLY water, a proper RO unit will filter out not only all the minerals but containment such as chlorine, chloramine, VOC, bacteria, viruses, lead and anything else your worried about.
Don't listen to me though, my opinion is bias as I used to sell these units.
.