In order to stay healthy, you have to do more than just drink 64 to 80 ounces of water every day, however. You also need to make sure that your drinking water is clean and clear of all dangerous impurities. It’s hard to overemphasize the importance of clean water; after all, about 4 billion people around the world get sick every year from drinking water that contains bacteria and other micro-organisms. While this mostly happens in undeveloped countries, it can still occur in places where water purification is common. After all, anyone can make a mistake. Other contaminants, such as heavy metals and chemical residues, may contribute to long term health problems such as cancer.