Why is Reverse Osmosis so good Reverse osmosis water contains fewer contaminants, has lower sodium, has no parasites or bacteria, and is safer for cancer patients. It filters out pollutants through a membrane filter that doesn't allow solids and prominent microbes to pass through. Reverse Osmosis water is safe to drink. Though Reverse Osmosis removes hard minerals from water, it also removes a wide range of other contaminants which can have a negative health impact. The Pro's and Con's of Reverse Osmosis water Filtration: Pro #1: Reverse Osmosis filters the most contaminants. Pro #2: Reverse Osmosis is a safe, environmentally friendly Atmospheric to bottled water. Pro #3: Reverse Osmosis provides better water for cooking. Con #1: More water used/wasted. Con #2: Some noticeable pressure drop possible depending the device.