Is it okay to drink expired water?

While water itself does not expire, the plastic bottles that water is typically stored in can leach chemicals into the water over time. These chemicals can be harmful to your health, and can cause a variety of health problems including nausea, vomiting, and diarrhea. Additionally, expired water may contain bacteria that can cause illness. Drinking expired water can make you sick by potentially exposing you to dangerous and unwanted chemicals, as well as potentially harmful microscopic life forms.

It is generally not advisable to drink any beverage or food past its expiration date because of the associated health risks due to potential chemical or bacterial degradation.