We all know how important it is to stay hydrated. Without enough fluid in our system, we can’t perform normal bodily functions. We need water to survive.
That’s why many people have the habit of leaving a glass of water on their bedside table before they go to sleep. You might wake up thirsty in the middle of the night, and it’s nice to have something to drink within arm’s reach. But after that water has been out for a while, you might notice a change in taste or appearance. Why is that?
Whether it’s from the tap or from the bottle, water that’s been sitting overnight will start undergoing some chemical reactions. That’s because water absorbs the carbon dioxide from the environment. This alters its natural pH and makes it more acidic (which explains the off-taste). But if it’s been sitting out in a clean glass for just one night, it should be safe to drink.
Just be warned: this may still expose it to possible contamination (especially if you re-using a dirty glass). A lower pH also makes it easier for bacteria to grow, so you should always take precautions.
Be mindful especially of tap water that’s been stored for an extended period of time, and of the plastic water bottles that have been sitting in your hot car. Consuming either can expose you to germs or harmful chemicals like BPA.
