What is Purified Water?
Purified water is water that has been mechanically processed to remove impurities and contaminants. These can include chemicals, heavy metals like lead, and microorganisms such as bacteria and viruses. Water is considered 'purified' only if it has a total dissolved solids (TDS) level of less than 10 parts per million (PPM), a significantly lower threshold than standard tap water. The source of this water can be municipal tap water, groundwater, or surface water, all of which undergo intensive treatment to meet these high purity standards.
Common Purification Methods
Several advanced techniques are used to create purified water. The method chosen can influence the final mineral content and taste.
- Reverse Osmosis (RO): This process forces water through a semipermeable membrane that filters out dissolved inorganic solids and other contaminants at a molecular level. Many household and commercial purification systems use RO, sometimes with a final carbon filter to improve taste. However, RO can also strip away beneficial minerals, leading to a flatter taste.
- Distillation: This method involves boiling water to create steam and then condensing the steam back into a clean liquid form. Most impurities are left behind in the boiling vessel because they do not evaporate with the water. This results in very pure water, often used for medical and laboratory purposes, but is energy-intensive and also removes all minerals.
- Deionization (DI): Using ion exchange resins, this process removes charged mineral ions, resulting in highly demineralized water. DI water is primarily used in industrial or laboratory settings rather than for drinking.
- Carbon Filtration and UV Treatment: These methods are often used in conjunction with RO or distillation. Activated carbon filters remove chlorine, organic compounds, and improve taste. UV light is a disinfection step that uses ultraviolet rays to inactivate microorganisms by disrupting their DNA.
Is Purified Water Safe for Drinking?
For most individuals, drinking purified water is completely safe and, in many cases, a healthier choice than untreated water. The primary advantage is the removal of a broad spectrum of potentially harmful contaminants, offering peace of mind regarding waterborne diseases, heavy metals, and chemical pollutants. People with compromised immune systems, infants, and pregnant women can particularly benefit from the extra layer of safety purified water provides.
The Debate Over Mineral Content
A major point of discussion is the removal of beneficial minerals. Some purification methods, like distillation and reverse osmosis, remove nearly all dissolved minerals, including beneficial ones such as calcium and magnesium. The World Health Organization (WHO) and other experts point out that while these minerals are important for health, the vast majority of mineral intake comes from a balanced diet, not drinking water. For healthy individuals with a normal diet, drinking mineral-deficient water poses no risk of mineral deficiency. Some modern purification systems address this by remineralizing the water after the filtration process.
Benefits and Disadvantages of Purified Water
Benefits
- Reduced Contaminant Exposure: Effectively removes chlorine, heavy metals, pesticides, and microbial pathogens, which is a major health benefit.
- Improved Taste and Odor: The absence of chlorine and other chemical residues results in a clean, neutral taste that many people prefer.
- Better for Health Conditions: Provides a safer water source for those with weakened immune systems or sensitive digestive tracts.
- Supports Kidney Function: Reduces the toxic load on kidneys, allowing them to filter metabolic waste more efficiently.
Disadvantages
- Potential for Mineral Loss: Processes like RO and distillation remove both bad and good minerals, which can require dietary compensation.
- Higher Cost: Buying bottled purified water or installing a home purification system is more expensive than consuming tap water.
- Environmental Impact: Bottled purified water contributes significantly to plastic waste and carbon emissions from production and transportation.
- Can Taste Flat: The lack of dissolved minerals can give the water a flat or empty taste, which might discourage some people from drinking enough water.
Comparison: Purified Water vs. Other Water Types
| Feature | Purified Water | Tap Water | Distilled Water | Filtered Water |
|---|---|---|---|---|
| Source | Filtered from any source (tap, well, surface water) | Municipal supply | Boiled and recondensed water from any source | Tap or well water |
| Treatment | Advanced filtration (RO, UV, carbon) | Chlorination, sometimes fluoridation | Distillation via boiling and condensation | Carbon, ceramic, or sediment filters |
| Contaminant Removal | Very high (99% of dissolved solids) | Low to moderate (depends on infrastructure) | Extremely high (removes most contaminants) | Low to high (depends on filter type) |
| Mineral Content | Low to none; some systems re-add minerals | Variable; contains some beneficial minerals | None (completely demineralized) | Some retained; depends on filter type |
| Taste | Clean, neutral taste | Can have chlorine or metallic taste | Flat, “empty” taste | Usually improved over tap water |
| Primary Use | Daily drinking, households with concerns over tap quality | Everyday drinking in areas with reliable infrastructure | Medical use, laboratory work, small appliances | Everyday drinking to improve taste and remove basic contaminants |
Conclusion
So, is purified water ok for drinking? The answer is a clear yes, particularly for individuals seeking the highest level of safety from contaminants. By effectively removing bacteria, viruses, chemicals, and heavy metals, purified water offers a reliable and clean hydration source. The main consideration is the removal of beneficial minerals by some purification methods. For most people with a balanced diet, this is not a concern, as dietary intake provides sufficient minerals. However, for those with specific health conditions or dietary needs, consulting a healthcare provider or opting for remineralized purified water may be a wise choice. Weighing the pros of safety against the cons of cost and potential mineral loss, purified water remains a solid and health-conscious option for a wide range of consumers.
Frequently Asked Questions
Is it safe to drink purified water every day?
Yes, for most people, it is perfectly safe to drink purified water every day. The mineral content, which is low or absent in some purified water, is typically replenished through a balanced diet.
Is purified water better than spring water?
Purified water guarantees a high level of purity by removing contaminants, while spring water's quality can vary depending on its natural source. If consistent safety is your priority, purified water is the better choice.
Does purified water leach minerals from your body?
No, this is a myth. While purified water has a lower mineral content, it does not actively pull minerals out of your body. The body maintains its mineral balance through diet and regulation.
Is purified water good for the kidneys?
Yes. By removing toxins and heavy metals, purified water reduces the toxic load on your kidneys, helping them function more efficiently.
What are the disadvantages of purified water?
Disadvantages include the potential loss of beneficial minerals, a sometimes flat taste, higher cost than tap water, and the environmental impact of bottled options.
Should babies drink purified water?
Purified water is a safe choice for preparing infant formula, but for babies under six months, plain water is not necessary as hydration is met through breast milk or formula. Consult a pediatrician for specific guidance.
What is the difference between purified and filtered water?
Purified water undergoes a more rigorous process (like RO or distillation) to achieve a higher standard of purity (less than 10 PPM TDS) than standard filtered water, which simply passes through a filter (e.g., carbon) to remove taste and odors.
