To make distilled water, water is heated to the boiling point. This creates vapor (or steam), which is captured, cooled to return to a liquid state, and bottled. Most of the contaminants in the water are removed during the distillation process.
Is distilled water healthier than tap water? It's debatable. Distilled water is generally free from contaminants and bacteria. However, the distillation process also removes minerals that can be healthful. Evidence suggests that drinking distilled water is fine for your body, but not necessarily healthier than most other types of drinking water.
The following nutrition information is provided by the USDA for 8 fluid ounces (240mL) of distilled water.
Like most forms of drinking water, distilled water has no calories. There are also no carbohydrates.
There is no fat in distilled water.
Distilled water provides no protein.
Distilled water differs from traditional tap water in that the minerals have been removed through the distillation process. Therefore, distilled water provides no vitamins or minerals.
According to the Centers for Disease Control and Prevention (CDC), the distillation process is very effective at removing protozoa (such as cryptosporidium or giardia), bacteria (such as campylobacter, salmonella, shigella, E. coli), and viruses (including enteric, hepatitis A, norovirus, and rotavirus).
Distillation also removes chemical contaminants, including arsenic, barium, cadmium, chromium, lead, nitrate, sodium, sulfate, and many organic chemicals, according to the CDC. However, all community water systems must meet the standards of the Safe Drinking Water Act, which sets safe levels for these contaminants. The Food and Drug Administration uses similar standards to regulate bottled water.
If your immune system is compromised or suppressed, your doctor may recommend that you drink distilled water since it is free from harmful organisms. Cryptosporidium (also known as "crypto"), for example, can cause or exacerbate illness. While other methods do not eliminate crypto from the water supply, distillation kills it. Reverse osmosis also kills the virus.
Some people on low-sodium diets prefer distilled water because the sodium in it has been removed. While most tap water does contain sodium, levels are still quite low, so distilled water may not be necessary. If you are on a low-sodium diet, discuss this with your doctor or a registered dietitian.
Drinking enough water is critical for health and wellness. If knowing that your water is distilled encourages you to drink more, it may be a good choice for you (but make sure you are getting minerals through food sources).
While there is no reported case of allergy attributed to distilled water, there are rare cases of an allergy to water. This is called aquagenic urticaria and according to the National Institutes of Health, it is a rare condition in which hives or itching develops after the skin comes in contact with water. Since it is so rare, there is limited information about effective treatments. Drinking or washing with distilled water does not help alleviate or prevent this condition.
Many essential minerals naturally present in water are eliminated in the distillation process. These may include calcium, magnesium, iodine, fluorine, and lithium, although in trace amounts. If you consume water for the purpose of gaining these minerals, you won't get them from distilled water. If you cook with distilled water, you will also miss out on minerals that you would otherwise get from water.
Most health experts advise that we get our vitamins and minerals from food. This is even more important if you do not get any minerals from water.
You can buy a countertop distiller to make your own distilled water at home. You can also buy distilled water at most grocery stores.
Keep unopened bottles of distilled water in a cool, dry place out of the sun. It does not need to be refrigerated unless you prefer the taste of chilled water.
Distilled water has no taste, although some people find this lack of taste unpleasant if they are used to the faint flavor of tap water with minerals. You can drink distilled water just like you drink other types of water. You can also use it in recipes just like you use tap or bottled water, and use it to make ice.
Some parents prefer to use distilled water to prepare baby formula. This is safe, but not necessary. It's more important is that water used in formula does not have too much fluoride. Many bottled waters and tap waters meet this standard.
While distilled water is sometimes recommended for brewing tea and coffee, it may not work well for either in terms of flavor. However, it will prevent mineral build-up in coffee machines and electric kettles.
There are other household uses for distilled water, including: