The Problem with Mineral-Free Water
Distillation is a purification process that involves boiling water and condensing the steam back into a liquid form. While this effectively removes harmful contaminants, it also strips the water of all its natural minerals and electrolytes, such as calcium, magnesium, and potassium. For adults, these minerals are crucial for a range of bodily functions, and relying solely on water that lacks them can disrupt the body's delicate internal chemistry.
Electrolyte Imbalance and Dehydration
Electrolytes are electrically charged minerals that play a vital role in nerve and muscle function, and maintaining proper hydration levels. When an adult drinks distilled water exclusively, they are not replenishing the electrolytes lost through sweating and urination. The World Health Organization has noted that drinking water with a low mineral content can lead to an increase in urine output, which can further compound the issue of electrolyte imbalance. In severe cases, particularly if combined with a poor diet, this can lead to symptoms like fatigue, muscle cramps, and headaches. The idea that distilled water is more hydrating is a misconception; in fact, the lack of electrolytes can make it less effective for rehydration, especially after vigorous exercise.
The Lack of Essential Minerals
Beyond just electrolytes, distilled water offers zero dietary minerals. While it is true that most of our mineral intake comes from food, water is an important supplementary source, especially for key minerals like calcium and magnesium. These minerals are vital for bone density, cardiovascular health, and nervous system function. The WHO has linked low-mineral water consumption to an increased risk of heart disease and motor neuron diseases. Cooking with distilled water can also drastically reduce the mineral content of food, with some studies suggesting losses of up to 60% for calcium and magnesium.
The "Leaching" Myth and Corrosive Nature
A common claim is that distilled water actively 'leaches' minerals from bones and tissues. While some sources have debunked this as a myth based on flawed science, the reality is more nuanced. The danger lies not in the water aggressively 'pulling' minerals from your body, but rather in your body being unable to replenish the minerals it naturally loses. On another note, demineralized water is known to be highly aggressive and corrosive to plumbing materials, which can cause it to leach toxic metals from pipes, a legitimate concern noted by the WHO.
The Palatability Problem
Another significant issue with relying on distilled water is its taste. Because all dissolved gases and minerals are removed, the water has a 'flat' or 'bland' taste that many people find unappealing. This can inadvertently lead to lower overall water consumption, increasing the risk of dehydration over time. For consistent, healthy hydration, a palatable water source is a major factor in ensuring an adequate daily intake.
Distilled vs. Other Water Types
To better understand why daily drinking of distilled water is discouraged, it helps to compare it to other common water types.
| Feature | Distilled Water | Tap Water | Purified Water (RO) | Spring Water |
|---|---|---|---|---|
| Mineral Content | No minerals | Varies by location | Very low (some may be added) | Contains minerals |
| Purity | Extremely high (pure H₂O) | Varies; contains minerals and potentially chemicals | High; removes most contaminants | Filtered naturally; contains minerals |
| Taste | Flat and bland | Varies by location; can have chemical taste | Clean, neutral | Refreshing; often has a pleasant taste |
| Cost | Higher for home distillation or bottled | Low | Moderate for home systems | Varies; often bottled and costly |
| Hydration | Less effective for rehydration due to lack of electrolytes | Effective | Effective (especially if remineralized) | Effective |
| Best Use | Appliances, lab work, CPAP machines | Daily consumption in safe areas | Daily consumption | Daily consumption |
Safe Alternatives for Daily Hydration
Instead of relying on distilled water for daily drinking, adults have several better options that provide safe and effective hydration without the risks associated with mineral deficiency:
- Tap Water: In regions with safe public water systems, tap water is often a healthy and readily available source of hydration, containing naturally occurring minerals.
- Purified Water (RO): Purified water, created through processes like reverse osmosis, removes most contaminants but is often remineralized by manufacturers for better taste and nutritional value.
- Spring Water: Bottled spring water is naturally filtered and contains minerals acquired from its journey through the earth, offering a crisp taste and mineral content.
- Filtered Water: At-home water filters can remove impurities while retaining beneficial minerals, making them an excellent choice for improving the quality of your drinking water without stripping it of all its health benefits. Culligan provides more information on different types of water purification.
Conclusion: Balancing Purity with Health
While distilled water is the purest form of H₂O, its lack of essential minerals and electrolytes makes it an unsuitable primary drinking source for adults. Long-term consumption can lead to deficiencies that impact metabolic function, electrolyte balance, and overall hydration effectiveness. For specific applications like CPAP machines or humidifiers where mineral deposits are a concern, distilled water is ideal. However, for a healthy adult's daily hydration, safer and more effective alternatives exist that provide not only clean water but also the vital minerals needed for optimal health.
