What Are the Dangers of Drinking Distilled Water?

Distillation is a process that extracts all of water's mineral content. Although distilled water is indicated in the production of medicines and car batteries, people should not use it as drinking water. According to the World Health Organization, drinking water should contain minimum levels of certain important minerals such as calcium and magnesium. Drinking distilled water can cause health problems including mineral deficiency, hyponatremic shock and increased risks of heavy metal intoxication.

When in the human body, water always contains electrolytes, which are electrically charged atoms of minerals such as potassium and sodium. Water absorption happens in the intestine with the help of these electrolytes. If a person drinks distilled water, the intestine needs to take electrolytes from the body reserves to be able to absorb the water. Symptoms of low mineral levels include tiredness, weakness and headache; muscular cramps; impaired heart rate; and fragile bones and teeth.

Experiments in rats showed evidence that the consumption of distilled water can increase water intake and extracellular fluid volume, eliminating sodium, potassium, chloride, calcium and magnesium from the body, and lowering the volumes of red cells, according to the World Health Organization. Regular intake of distilled water can cause hyponatremic shock or "water intoxication," which often happens after intense physical efforts and the ingestion of big quantities of water. Symptoms range from drowsiness and irritability to convulsions and cerebral edema, which is retention of water in the brain. When specifically related to low absorption of potassium, it is called hypokalemia.

Distilled water absorbs metals and other substances from storage tanks and containers in a higher rate compared with drinking water. Consuming distilled water can reduce the levels of important minerals such as calcium and magnesium. According to the World Health Organization, calcium and magnesium have anti-toxic activity, and in case of ingestion of contaminated water or food, these minerals prevent the absorption of heavy metals such as lead and cadmium from the intestines into the blood.