What is water with no minerals?
Water with no minerals, often called demineralized, distilled, or reverse osmosis (RO) water, is purified water stripped of its dissolved mineral content. While tap water and natural spring water contain trace amounts of minerals like calcium, magnesium, and potassium that are picked up as it moves through rocks and soil, demineralized water has had these ions and impurities removed through various technological processes. The primary methods for creating water with no minerals include:
- Distillation: This process involves boiling water and collecting the resulting steam. As the water evaporates, it leaves behind minerals, chemicals, and other impurities. The condensed steam is exceptionally pure, containing almost no mineral content.
- Deionization (DI): This is a more technical method that uses ion exchange resins to attract and remove charged mineral ions from the water. While highly effective at removing minerals, it does not remove uncharged contaminants like bacteria or viruses, which can remain unless other filtration steps are included.
- Reverse Osmosis (RO): A popular method for in-home use, RO pushes water through a semi-permeable membrane that traps minerals, salts, and other impurities. Like distillation, it is highly effective at purifying water but also removes most of the beneficial minerals.
Potential risks of drinking demineralized water
For most people with a balanced and nutrient-rich diet, drinking demineralized water intermittently is unlikely to cause serious problems. However, long-term, exclusive consumption comes with several documented risks, as highlighted by numerous studies and health organizations like the WHO.
1. Mineral Deficiency: The most significant risk of drinking only demineralized water over time is the potential for mineral deficiencies, especially in calcium and magnesium. While diet is the primary source of these minerals, the small amounts obtained from water can provide a protective effect. When this supplement is removed, and especially if one's diet is already borderline deficient, health can be negatively impacted. Studies on populations that rely on low-mineral water have shown correlations with lower bone mineral density, increased risk of fractures, and potential cardiovascular disorders.
2. Electrolyte Imbalance: The lack of minerals in demineralized water can disrupt the body's delicate electrolyte balance, which is crucial for nerve and muscle function. Research has shown that consuming low-mineral water can lead to increased diuresis (urine output), affecting serum concentrations of electrolytes like sodium and potassium. Early symptoms can include tiredness, weakness, and headaches, while more severe cases can result in muscular cramps or an impaired heart rate.
3. Leaching of Minerals from Food: Cooking with demineralized water can cause a significant loss of essential minerals from foods. Studies have shown that when vegetables are cooked in water with no minerals, they can lose up to 60% of their calcium and magnesium, with even higher losses for some micro-elements. This process further reduces the nutritional value of one's food and can contribute to overall mineral deficiencies.
4. Corrosive Nature: Without its natural buffer of minerals, demineralized water is highly aggressive and will leach metals and other substances from any pipes, fittings, or containers it comes into contact with. This can increase the intake of potentially toxic metals like lead, especially from older plumbing systems. Natural minerals in water offer a protective effect by forming a barrier against such leaching.
5. Unappealing Taste: Many people find the taste of demineralized water to be flat, bland, or unappealing due to the absence of minerals. This can discourage adequate water consumption, potentially leading to dehydration.
Potential benefits of drinking demineralized water
Despite the risks of long-term exclusive use, demineralized water does have its place and offers specific benefits:
- High Purity: The primary benefit is its high purity. The removal of contaminants like bacteria, viruses, and chemicals (including chlorine) makes it useful in medical facilities, laboratories, and specific industrial processes where pure water is required.
- Free from Harmful Contaminants: In areas with contaminated water sources, a high-quality RO or distillation system can provide a reliable source of purified water, free from heavy metals like lead and other pollutants.
Demineralized vs. Mineralized Water Comparison
| Feature | Demineralized Water (Distilled, RO) | Mineralized Water (Tap, Spring) |
|---|---|---|
| Mineral Content | Almost none. Calcium, magnesium, and other essential minerals are removed during processing. | Contains naturally occurring minerals that vary based on source and location. |
| Taste | Often described as flat, bland, or lacking flavor due to the absence of minerals. | Has a more refreshing taste, often influenced by its mineral composition. |
| Health Impact | Long-term use can lead to mineral deficiencies and electrolyte imbalances. Can be corrosive. | Provides a supplemental source of essential minerals like calcium and magnesium. |
| Primary Source of Minerals | Does not contribute to mineral intake. | Contributes a small but bioavailable amount of daily mineral intake. |
| Best for Daily Drinking | Not recommended for long-term, exclusive consumption unless remineralized. | Recommended for daily hydration, as it contributes to mineral balance. |
| Ideal Uses | Medical equipment, laboratory experiments, industrial applications, appliances to prevent mineral buildup. | General hydration, cooking (maintains food nutrients), and everyday use. |
Conclusion
While water with no minerals is safe for occasional consumption and useful for specific industrial or medical applications, long-term and exclusive use is not recommended for general health. The World Health Organization and other health experts have raised concerns about the potential for mineral deficiencies and electrolyte imbalances resulting from prolonged intake. Your body relies on a balanced intake of minerals, and while food is the primary source, the supplemental minerals in regular drinking water provide a protective effect that should not be overlooked.
For those who use purification systems like reverse osmosis, options exist to remineralize the water before consumption, which restores beneficial minerals and improves taste. Ultimately, a conscious decision should be made based on your dietary habits and health needs. For most people, a balanced and varied diet, combined with regular mineralized drinking water, is the best path to overall wellness. Always consult a healthcare professional to discuss concerns regarding your specific dietary needs and hydration choices.
