The Aggressive Nature of Deionized Water
Deionized water is often called "hungry" water because its lack of dissolved ions makes it an excellent solvent, actively seeking to regain a balanced mineral composition. When ingested, this aggressive nature can pose health hazards. Instead of receiving beneficial minerals, your body may be stripped of its own essential electrolytes, creating a mineral imbalance. This occurs because the pure water will actively absorb minerals from anything it contacts, including the tissues in your digestive tract.
How This Mineral Leaching Affects Your Body
The process of deionization removes beneficial minerals like calcium, magnesium, and potassium, which are vital for proper nerve function, muscle contraction, and maintaining a healthy electrolyte balance. Long-term consumption of demineralized water can contribute to these deficiencies, potentially impacting everything from heart function to bone health. While drinking water isn't the primary source of these minerals, its contribution is significant, especially for those with mineral-deficient diets. Some research suggests that populations consuming low-mineral water may experience higher rates of cardiovascular issues.
The Risk of Toxic Metal Contamination
Beyond stripping your body of minerals, deionized water's corrosive properties also pose another threat. As the water passes through plumbing systems or is stored in containers, its aggressive nature can cause it to leach metals and other substances from the materials it touches. This can introduce toxic metals like lead from older pipes into your drinking water, increasing your dietary intake of harmful substances. Standard mineralized water is less aggressive and poses a much lower risk of this kind of contamination.
The Problem of Pathogens
One of the most critical reasons you cannot drink deionized water directly is that the deionization process does not remove uncharged contaminants, such as bacteria and viruses. Deionization uses an ion exchange process that targets only charged particles (ions). This means that water coming directly from a deionization system, even if it started from a treated municipal source, could still harbor dangerous microorganisms. For drinking, water requires sterilization methods that deionization doesn't provide, such as distillation or reverse osmosis combined with additional filtration and disinfection.
Comparison: Deionized Water vs. Tap Water
To better understand the risks, let's compare deionized water to standard tap water, which is treated for safety and contains natural minerals.
| Feature | Deionized Water | Tap Water |
|---|---|---|
| Mineral Content | Almost completely devoid of mineral ions (e.g., calcium, magnesium). | Contains a variety of dissolved mineral ions, which contribute to its taste and nutritional value. |
| Contaminants | Removes only charged ions, leaving uncharged pathogens like viruses and bacteria. | Treated by municipal facilities to remove or inactivate harmful microorganisms and other contaminants. |
| Corrosiveness | Highly aggressive and can leach toxic metals from pipes and storage containers. | Generally non-aggressive due to its mineral content, which makes it more stable. |
| Taste | Often described as flat, bland, or unappealing due to the lack of minerals. | Flavor varies depending on the specific mineral composition of the water source. |
| Intended Use | Industrial and laboratory applications requiring high-purity water. | Safe for drinking and everyday household uses, such as cooking and bathing. |
What if Deionized Water is Remineralized?
In some cases, such as in certain bottling plants, water is deionized and then re-mineralized with specific elements to make it suitable for drinking. This process is controlled to add back essential minerals in safe quantities. However, consuming deionized water that has not been specifically re-mineralized for human consumption is still ill-advised. The controlled re-mineralization process is a crucial step that is absent when one simply consumes DI water directly from a lab-grade source.
Conclusion
While the concept of "pure" water might sound appealing, the reality is that deionized water is not designed for human consumption. Its lack of essential minerals can lead to an electrolyte imbalance, while its corrosive and non-sterile nature presents additional risks of toxic metal leaching and bacterial contamination. For everyday hydration, stick to tap water or other forms of filtered water that retain or re-add beneficial minerals. Deionized water has its important uses in industrial and scientific settings, but should remain in the laboratory, not in your glass.
