What Exactly is Distilled Water?
Distilled water is a form of highly purified water produced through the process of distillation. This method involves boiling water to create steam, leaving behind impurities with higher boiling points, such as minerals, salts, and heavy metals. The steam is then collected and cooled until it condenses back into a liquid state, which is the final distilled water. This process is highly effective at removing contaminants, which is why distilled water is favored for industrial, medical, and laboratory applications where extreme purity is required. However, the same process that removes harmful impurities also removes beneficial, naturally occurring minerals like calcium and magnesium. This lack of minerals gives distilled water a characteristically flat, unappealing taste to many consumers.
The Truth About Bottled Water
The blanket term "bottled water" covers a wide range of products, and rarely is it exclusively distilled. To determine what you're buying, the most reliable method is to read the label. The FDA regulates bottled water labels in the United States, which must accurately describe the product inside.
Common Bottled Water Types
- Purified Water: This is one of the most common types of bottled water and is often sourced from municipal water supplies before being extensively filtered. The purification process typically involves reverse osmosis (RO), deionization, or another form of advanced filtration to remove impurities. Following purification, some manufacturers add a blend of minerals, such as magnesium sulfate and potassium chloride, for a more palatable taste. Aquafina and Dasani are two well-known examples of purified bottled water.
- Spring Water: This water comes from a natural underground formation from which water flows naturally to the Earth's surface. The water is collected at the source or through a borehole that taps into the spring. Spring water is naturally filtered through layers of rock and soil, and as a result, it contains natural minerals that contribute to its unique taste. Unlike purified water, spring water retains its natural mineral composition and typically undergoes minimal processing before bottling.
- Mineral Water: Similar to spring water, mineral water is sourced from a geologically and physically protected underground water source. The key difference is that mineral water must contain a constant level and proportion of minerals and trace elements. It is bottled directly at the source and no minerals can be added.
Distilled Water vs. Drinking Water: What's the Right Choice?
Because distilled water is nearly devoid of all dissolved solids, it has very specific applications where this purity is essential. For regular drinking, however, it's often not the preferred choice.
Best Uses for Distilled Water
- Medical Equipment: CPAP machines require distilled water to prevent mineral buildup and ensure clean, moist air is delivered during sleep.
- Steam Irons: Using distilled water prevents mineral scaling inside the iron, which can clog steam vents and damage fabrics over time.
- Laboratories: Scientists use distilled water to prevent impurities from interfering with sensitive experiments and procedures.
- Car Batteries and Cooling Systems: The absence of minerals prevents corrosion and buildup inside automotive systems.
Best Uses for Drinking Water (Purified, Spring, Mineral)
- Daily Hydration: Purified and spring water contain minerals that are often preferred for taste and can contribute to overall mineral intake. While not the primary source of minerals for a healthy diet, they offer a more balanced and palatable option for everyday drinking.
- Cooking: For daily cooking and brewing coffee or tea, most people prefer the taste of purified or spring water over the flat taste of distilled water.
- Replenishing Electrolytes: Following intense exercise or illness, water with a mineral content is more effective at replenishing lost electrolytes.
Making an Informed Decision
When choosing bottled water, the label provides the most important information. The phrases “purified water,” “spring water,” and “distilled water” each refer to a distinct product with different properties. Understanding these differences allows you to choose the right type of water for your specific needs, whether for hydration or a specific household or medical use.
The Bottled Water Landscape
While the market is flooded with many varieties, a quick check of the label is the best way to determine the type of water you're buying. For example, some brands like Glaceau Smartwater start with distilled water before adding electrolytes back in for taste. This means you can find water that has been distilled, but it is not commonly sold as pure, mineral-free distilled water intended for drinking. The vast majority of commercially available bottled water for drinking will be purified (often by reverse osmosis) or spring water.
The Environmental Factor
It is also worth considering the significant environmental impact of bottled water. The manufacturing, filling, and transportation of plastic bottles, especially those shipped from across the globe, consume large amounts of energy and contribute significantly to carbon emissions. Furthermore, only a fraction of plastic bottles are recycled, and they can leach harmful microplastics into the water over time. For those concerned about tap water safety, at-home filters are a more cost-effective and environmentally friendly option.
The Final Word
Ultimately, the choice between different bottled water types depends on your purpose. For everyday drinking, spring or purified water offers a more familiar and palatable taste, while providing some mineral content. For applications where purity is paramount, such as medical devices or car maintenance, distilled water is the only reliable option. By reading the label and understanding the processes involved, consumers can make a smarter, more targeted decision.
| Feature | Distilled Water | Purified Water | Spring Water |
|---|---|---|---|
| Purification Method | Boiling into steam and recondensing | Reverse Osmosis, deionization, filtration | Naturally filtered through rocks and soil |
| Mineral Content | Almost entirely mineral-free | Mineral-free, but minerals are often added back | Contains naturally occurring minerals |
| Taste | Flat and bland | Consistent taste profile, often enhanced | Unique taste based on source and mineral content |
| Common Uses | Medical devices (CPAP), irons, labs, batteries | Daily drinking, cooking | Daily drinking |
| Key Characteristic | Utmost purity, no dissolved solids | Highly filtered and treated | Natural origin, unique mineral profile |
Conclusion
In conclusion, most bottled water on the market is not distilled but is instead purified through processes like reverse osmosis or sold as natural spring water. Distilled water is a specific type of purified water, characterized by its lack of minerals and flat taste, making it ideal for high-ppurity applications rather than everyday drinking. To know exactly what you're purchasing, always check the product label for the specific type of water and its purification method.
For more detailed information on bottled water regulations and types, consult the FDA's website for food and beverage standards. https://www.fda.gov/food/bottled-water/bottled-water-faqs
