Is Distilled Water Safe to Drink?

It is sold as bottled drinking water. The FDA's bottled water standard says water produced by distillation, deionization, reverse osmosis or other suitable processes that meets the US Pharmacopeia definition of purified water may be named purified water or demineralized water, or distilled water when it is produced by distillation. CDC says bottled water can come from sources such as public tap water systems or underground sources, and that no matter its source, bottled water must meet safe drinking water standards.

CDC says distillation systems boil water and then collect the water as it cools, leaving behind many of the germs and chemicals that were in it. It says distillation removes chemicals including arsenic, barium, cadmium, chromium, lead, nitrate, sodium, sulfate, calcium, magnesium and many organic chemicals, but does not remove some volatile organic compounds, volatile solvents and certain pesticides, and that while distillation removes bacteria, bacteria may grow on a system's cooling coils while it is not being used.

A World Health Organization report raises a nutrition question. Its 2005 report Nutrients in Drinking Water says people who regularly drink unreconstituted desalinated or distilled water may be receiving smaller amounts of some nutrients than people drinking water from more traditional sources, and are disadvantaged if their diets do not provide enough. A chapter on demineralised water in the report concludes that drinking water should contain minimum levels of certain essential minerals, and notes that distilled water has poor taste characteristics.