You need to know that the water you are drinking is safe. If your water isn't safe - then you are in big trouble! It's true that God put a LOT of water on earth - and humans often do things to taint that water.

But even if you start with pure water (ie from a reverse osmosis filter), if you drink from a plastic container or water bottle, the water will now have dangerous chemicals mixed with it. These chemicals are reported to have severe health effects from reproduction issues to cancer.

Only materials that do not deteriorate and seep into the water are safe. Glass is one and Stainless steel is another.

As glass is heavy, fragile and dangerous - Stainless Steel is an obvious choice for Drinking bottles.