Understanding Demineralized Water
Demineralized water, also known as deionized (DI) water, is water that has had most or all of its mineral and salt ions removed through various purification processes. Unlike simple filtration, which removes larger impurities, demineralization targets specific ionic contaminants such as calcium, sodium, magnesium, chloride, and sulfate. The primary methods for achieving demineralization include ion exchange, reverse osmosis, and distillation. While this high-purity water is essential for many industrial, laboratory, and medical applications, its lack of mineral content raises important health concerns when considered for daily human consumption.
The Potential Health Risks of Demineralized Water Consumption
Research from the World Health Organization (WHO) and other studies indicates that long-term consumption of demineralized water can pose several health risks. These issues arise primarily from the absence of naturally occurring minerals that are crucial for bodily functions.
- Mineral and Electrolyte Deficiencies: The most direct risk is a mineral deficiency. Our bodies need trace minerals like calcium and magnesium to function correctly. When drinking water that is stripped of these minerals, the body may pull from its own reserves to maintain balance, leading to a net loss of essential electrolytes. This can impact metabolic functions and overall cellular health.
- Impact on Water and Mineral Metabolism: Studies cited by the WHO show that consuming water with a low total dissolved solids (TDS) count can cause increased urine output and changes in body water volume and sodium concentration. This can negatively affect the body's water-salt balance and potentially compromise organ function over time.
- Loss of Nutrients in Food: The use of demineralized water for cooking can significantly decrease the nutritional value of food. When cooking vegetables, meat, or cereals, the lack of minerals in the water can cause them to leach their own essential elements into the water, which is then discarded. This process can strip foods of vital minerals like calcium and magnesium.
- Increased Exposure to Toxic Metals: Demineralized water is considered 'aggressive' and can leach metals, including potentially toxic ones like lead and cadmium, from plumbing materials and storage tanks. This can increase the drinker's exposure to these harmful substances, which would typically be counteracted by the protective capacity of a more mineralized water source.
- Poor Taste and Hydration Issues: Many people find the taste of demineralized or distilled water to be flat or unappealing. This can result in lower overall water consumption, which could lead to inadequate hydration over time.
Demineralized vs. Distilled Water
While often confused, demineralized and distilled water differ in their purification methods and contaminant removal effectiveness. Both remove minerals, but distilled water is generally purer.
| Feature | Demineralized Water | Distilled Water |
|---|---|---|
| Purification Method | Ion exchange, reverse osmosis, or electrodialysis | Boiling and condensation |
| Purity | Removes almost all dissolved salts and minerals, but may retain some organics, viruses, or bacteria | Removes nearly all inorganic substances, as well as bacteria, viruses, and other impurities |
| Energy Use | Lower energy consumption, especially with ion exchange | Higher energy consumption due to boiling |
| Cost | Generally more economical for producing large volumes for industrial use | Can be more expensive and time-consuming for large volumes |
| Typical Use | Industrial applications, lab analysis, automotive, pharmaceutical manufacturing | Medical facilities, laboratories, and specialized applications requiring the highest purity |
How to Safely Consume Demineralized Water
For those with home reverse osmosis (RO) systems or other water purifiers that produce demineralized water, there are ways to mitigate the health risks. A key step is remineralization, which adds essential minerals back into the water.
- Inline Mineral Filters: Many modern RO systems offer an optional inline mineral filter (also known as a remineralizing or alkalinization stage) that adds back beneficial minerals like calcium and magnesium. These are a consistent and reliable solution for daily use.
- Liquid Trace Mineral Drops: For a more portable or flexible option, trace mineral drops can be added to a glass or bottle of water. This allows for customized mineral dosage, though it can be more expensive and less convenient for large quantities.
- Dietary Adjustments: Maintaining a balanced diet rich in fruits and vegetables can help compensate for the lack of minerals in drinking water. However, relying solely on diet may not be enough, especially for those with borderline deficiencies.
- Consult a Professional: Before making significant changes to your hydration source, it is advisable to consult a healthcare professional. They can provide guidance based on your personal needs and health conditions.
Conclusion
While demineralized water is a powerful tool for industrial and scientific applications, it is not recommended for long-term human consumption without proper remineralization. The removal of essential minerals like calcium and magnesium can lead to adverse health effects, including deficiencies and metabolic imbalances, as noted by the WHO. For individuals with advanced home purification systems, incorporating a remineralization stage or using mineral supplements is a crucial step to ensure the water is not only pure but also healthy to drink. By understanding the differences between demineralized and other water types, consumers can make informed choices to safeguard their hydration and overall well-being.
References
- World Health Organization (WHO) - Health Risks from Drinking Demineralised Water.
- Lenntech - Demineralized water FAQ.
- Atlas Scientific - What Is Demineralized Water?
- National Institutes of Health (NIH) - Demineralization of drinking water: Is it prudent?
- Medical News Today - Can you drink distilled water safely?
