What is purified water?
Purified water is water that has been mechanically filtered or processed to remove impurities and contaminants. These can include chemicals, heavy metals, pesticides, bacteria, and viruses. Common purification methods include distillation, reverse osmosis, and deionization. While the goal of purification is to achieve a higher degree of cleanliness than tap water, the process can also strip away naturally occurring beneficial minerals.
The purification process explained
Purification involves a series of steps to make water cleaner and safer to drink. Here are three common methods:
- Reverse Osmosis (RO): This method uses high pressure to force water through a semi-permeable membrane. The membrane is fine enough to block most dissolved solids, including minerals, salts, and many chemical contaminants.
- Distillation: This process involves boiling water and then condensing the steam back into a liquid. Impurities with a higher boiling point than water are left behind. This is one of the most effective ways to remove a wide range of contaminants, but it also removes virtually all minerals.
- Activated Carbon Filtration: While often part of a larger purification system, activated carbon filters use a porous material to trap and absorb contaminants like chlorine, volatile organic compounds (VOCs), and other compounds that affect taste and odor.
The health debate: Benefits vs. drawbacks
The core debate surrounding purified water centers on its purity versus its mineral content. Proponents argue that the removal of harmful contaminants is paramount for health, while critics point to the loss of beneficial minerals.
Benefits of purified water:
- Reduced exposure to contaminants: For areas with compromised water quality, purified water offers peace of mind by removing pollutants like lead, chlorine, and pesticides.
- Improved taste and odor: By removing chemicals like chlorine, purified water often has a cleaner, more neutral taste that many people prefer.
- Safe for sensitive populations: For individuals with weakened immune systems, infants, or those with specific medical conditions, purified water can be a safer option by eliminating bacteria and viruses.
- Improved athletic performance (if remineralized): Some systems reintroduce electrolytes like magnesium and potassium, which can aid in rehydration and performance, especially for athletes.
Drawbacks of purified water:
- Depletion of essential minerals: Purification methods like reverse osmosis and distillation remove minerals vital for health, such as calcium and magnesium. Long-term reliance solely on this water source could potentially lead to mineral imbalances.
- Potential for mineral leaching: Studies suggest that demineralized water can be slightly acidic and may have the potential to leach minerals from the body or from the plumbing it travels through.
- Impact on dental health: A lack of fluoride in purified water could increase the risk of tooth decay, especially in children.
- Flat taste: Some find the taste of demineralized water to be flat or insipid, which could discourage consistent hydration.
Purified water vs. tap water: A comparison
To understand the true value of purified water, it's helpful to compare it directly with standard tap water.
| Feature | Purified Water | Tap Water |
|---|---|---|
| Regulation | Regulated by the FDA (for bottled water), with standards that can be less stringent than the EPA's for municipal systems. | Highly regulated by the EPA in the US, with public water suppliers required to conduct regular testing and disclose results. |
| Contaminant Removal | Extensive. Removes a wide range of impurities, including bacteria, viruses, and chemicals. | Good, but varies by location and infrastructure. May contain traces of chlorine, lead, or other contaminants, particularly from older pipes. |
| Mineral Content | Low to non-existent, depending on the purification method. Some systems add minerals back in. | Varies greatly by source. Contains naturally occurring minerals like calcium and magnesium. |
| Taste and Odor | Neutral and clean, free from chemical tastes. | Can vary by location and treatment process. Sometimes has a metallic or chlorine-like taste. |
| Cost and Environment | Expensive, especially bottled versions. Contributes to plastic waste. Home systems require energy. | Inexpensive and readily available. More environmentally friendly, especially with a reusable bottle. |
How to get the best of both worlds
The debate isn't an all-or-nothing proposition. Many strategies exist to mitigate the drawbacks of purified water while still enjoying its benefits.
- Choose a system that remineralizes: Look for reverse osmosis systems that include a final stage to add essential minerals like calcium and magnesium back into the water. This restores both mineral content and a more pleasant taste.
- Balance your diet: If you use a purification method that removes minerals, you can compensate by ensuring your diet is rich in mineral-dense foods. Leafy greens, nuts, seeds, and dairy products are excellent sources of key minerals.
- Test your tap water: Before investing in a purification system, test your local tap water. In many regions with robust municipal water systems, tap water is perfectly safe and a more sustainable choice. A filter might only be needed for taste improvement or to remove specific localized contaminants.
- Consider activated carbon filtration: For general taste and odor improvement, an activated carbon filter pitcher or tap filter is a cost-effective and environmentally friendly alternative that retains natural minerals.
The bottom line: Is purified water pointless?
The notion that it's pointless to drink purified water is a misconception. The value of purified water depends entirely on the context of your personal health, your local water quality, and your dietary habits. It is not an inherently good or bad option but rather a tool to be used thoughtfully. For those living in areas with questionable water sources, purified water is a wise and potentially life-saving choice. For those with access to clean, reliable tap water, it may not be a necessity, but a preference. By understanding the pros, cons, and available alternatives, you can make a choice that truly benefits your health and hydration goals. Just remember that what you lose in minerals can often be easily replaced through a balanced diet, and the peace of mind from drinking clean water is invaluable.
