You may know distilled water as the stuff you buy to pour into an iron, but it’s actually one of the safest types of water to drink. You can count on distillation to kill harmful microorganisms not eliminated by all water treatment methods, reports the Centers for Disease Control and Prevention. While distillation removes beneficial minerals, it also gets rid of heavy metals and other contaminants.
The process of distilling water begins by collecting water in a tank and heating it to the boiling point. Steam that rises from the boiling water enters condensing coils, which are metal tubes twisted into a coil. As the steam travels through the coils, it cools down and turns back into water. The water that comes out of the coils is distilled. Boiling the water kills bacteria and other microorganisms. Minerals and other substances dissolved in the original water stay behind as the steam rises. In fact, distillation removes more than 99.9 percent of all minerals in water, reports the University of Georgia.
Free of Microorganisms
Distillation is the only purification process that eliminates harmful microorganisms with absolute certainty, reports the University of Illinois at Urbana-Champaign. This is a vital health benefit for anyone with a weak or compromised immune system, because distillation kills parasites that may not be affected by other treatment methods. One parasite, Cryptosporidium, is resistant to commonly used water disinfectants such as chlorine, but distillation kills it. Cryptosporidium can make healthy people sick and cause severe illness or even death if your immune system is weak. Those with weakened immune systems should use distilled water, according to the Centers for Disease Control and Prevention.
Even though distillation removes healthy minerals, the process also gets rid of heavy metals, including lead, mercury and arsenic. Distillation removes some but not all of the volatile organic chemicals in products such as cleaning fluids that tend to find their way into ground water. You also won’t get any nitrate in distilled water. Nitrate doesn’t cause health problems unless it’s converted into nitrite, which can interfere with the ability of red blood cells to carry oxygen. Nitrates in water are especially dangerous for pregnant women, infants and adults with low stomach acid, reports Colorado State University Extension.
Lack of Chlorine
Minerals dissolved in the water and the type of treatment used to purify it determine water's flavor. The flavor of distilled water is sometimes described as flat, because it doesn’t have any minerals, but distillation also gets rid of chlorine, and that may be a flavor benefit. Regulated chlorine levels shouldn't be high enough to cause health problems, even when you can smell chlorine in water. If you’re sensitive to its odor, however, you may find distilled water more appealing, and that may motivate you to drink more water.
- University of Illinois at Urbana-Champaign: Safe Drinking Water
- University of Georgia Extension: Water Quality and Common Treatments for Private Drinking Water Systems
- Centers for Disease Control and Prevention: Commercially Bottled Water
- New Jersey Department of Health and Senior Services: Volatile Organic Compounds in Drinking Water
- Colorado State University Extension: Nitrates in Drinking Water
- University of Nebraska-Lincoln Extension: Drinking Water Treatment: Distillation
- U.S. Environmental Protection Agency: Basic Information About Disinfectants in Drinking Water: Chloramine, Chlorine and Chlorine Dioxide