Reverse osmosis water is very different from distilled water - but both are safe to drink. In general sense, mineral water refers to water that has been purified, treated, and bottled for drinking. Mineral water is usually naturally enriched with minerals right from the source: live streams, springs etc. It does not require any form of purification. Most of the water that we get from the store isn’t necessarily from these sources, though. But it has been purified and minerals added. Reverse osmosis water, on the other hand, is water that has been passed through semi-permeable membranes to get rid of most of the contaminants. This membrane eliminates chlorine, metals, bacteria, and other forms of impurities thereby making it absolutely safe for drinking. However, keep in mind that that most Reverse Osmosis water treatment systems also remove minerals from the water. The good news is that some of the latest models in our best reverse osmosis systems reviews above are engineered to retain the minerals.