When choosing safer drinking water, many people wonder: what's the difference between distilled water and purified water? According to the U.S. Environmental Protection Agency (EPA), both types of water must meet rigorous safety standards, ensuring they are free from harmful contaminants when properly purified. While both are ultra-clean, they're not identical. Understanding how each is made, their health effects, and best uses helps you choose wisely.
Distilled water removes virtually everything through boiling and steam collection, while purified water uses various filtration methods that may keep some beneficial minerals. This article compares their processes, health impacts, taste differences, costs, and environmental effects to help you make the right choice for your needs.
Quick Comparison — Distilled Water vs Purified Water
| Feature | Distilled Water | Purified Water |
| Process | Boiling water and collecting steam | Multiple methods: reverse osmosis, ion exchange, carbon filtration |
| Mineral Content | None or negligible | May retain trace minerals depending on process |
| Taste | Flat, bland flavor | Smoother taste, sometimes slightly mineralized |
| Safety & Health | Ultra-pure, requires dietary minerals | Clean with possible trace mineral benefits |
| Primary Uses | Medical facilities, baby formula, appliances, labs | Daily drinking, cooking, offices, general consumption |
| Environmental Impact | High energy use from boiling | Varies by method, generally less energy-intensive |
In the quick comparison of "Distilled Water vs Purified Water," we see clear differences in the processes, mineral content, taste, safety, and primary uses of each. Distilled water, created by boiling water and collecting steam, is ideal for specialized uses like medical facilities, baby formula, and appliances. In contrast, purified water uses various methods like reverse osmosis and ion exchange, making it more suitable for daily drinking and cooking. While both offer safe drinking water, your choice will depend on your specific needs. The following sections will dive deeper into the health impacts, ideal uses, and how to choose the best option for you.
What is Distilled Water?
Distilled water is created through a simple but effective process: boiling water and collecting the steam. As water turns to vapor, it leaves behind nearly all contaminants, including bacteria, viruses, metals, and minerals. The steam then condenses back into liquid form, creating extremely pure water.
This water purification method removes:
- Heavy metals like lead and mercury
- Bacteria and viruses
- Chemical contaminants
- All minerals, both harmful and beneficial
- Dissolved salts and particles
When to Use Distilled Water
Distilled water is often the preferred choice for:
- Medical and laboratory settings where absolute purity matters
- Baby formula preparation to avoid harmful contaminants
- Steam appliances like irons and humidifiers to prevent mineral buildup
- Car batteries and other equipment requiring pure water
- Photography and scientific experiments where minerals could interfere
The difference between distilled and purified water becomes clear here - distilled water's complete lack of minerals makes it ideal for these specialized uses.
What is Purified Water?
Purified water encompasses several water treatment processes that remove contaminants while potentially keeping some beneficial elements. So, is purified water distilled? While both are highly purified, purified water can undergo various filtration methods that may retain some beneficial minerals, unlike distilled water, which removes everything, including those minerals.The most common methods include:
Reverse Osmosis Water
This process forces water through extremely fine membranes that remove contaminants while allowing water molecules to pass through. Reverse osmosis water eliminates most harmful substances but may retain small amounts of minerals.
Ion Exchange
Ion exchange is a water treatment method that replaces harmful ions, such as calcium and magnesium, with safer ions like sodium or potassium. This process not only purifies the water by removing undesirable contaminants but also helps retain some beneficial minerals, ensuring the water maintains a balanced taste and mineral content.
Carbon Filtration
Carbon filtration uses activated carbon to effectively absorb chemicals, chlorine, and organic compounds from water, improving its taste and safety. This method is highly efficient at removing impurities while maintaining essential minerals like calcium and magnesium, which contribute to both the water's flavor and its health benefits.
Ozonation
This process uses ozone gas to kill bacteria and viruses without removing all minerals from the water.
Purified water is water that has undergone at least one of these processes to meet safety standards. The type of purified water you get depends on which method was used.
The distinction between distilled vs purified water becomes clear here – purified water undergoes multiple filtration processes that remove contaminants while retaining some beneficial minerals.
What are the Disadvantages of Distilled Water?
While distilled water offers many benefits, especially in terms of purity, it does have some potential drawbacks:
- Lack of Essential Minerals: Distilled water is completely devoid of minerals, such as calcium and magnesium, which are beneficial for health. Long-term consumption of distilled water may contribute to mineral deficiencies, unless these nutrients are obtained through diet.
- Flat Taste: The absence of minerals makes distilled water taste flat or bland compared to purified water, which retains some trace minerals that enhance its flavor.
- Potential for Increased Toxicity: Distilled water is highly pure, which can increase the rate at which the body absorbs certain toxic metals (such as lead) from the environment or food, as it lacks the minerals that would normally help detoxify or neutralize such substances.
- High Energy Consumption: The distillation process requires significant energy to heat water to its boiling point and collect the steam, making it less environmentally friendly and more expensive for large-scale production.
- Not Ideal for Everyday Consumption: While it’s great for specialized uses, such as in medical settings or for appliances, distilled water is not the best choice for daily hydration due to its lack of minerals and less pleasant taste.
What are the Disadvantages of Purified Water?
While purified water offers many benefits, potential drawbacks include:
- May not remove all contaminants depending on the purification method, as some methods may leave behind trace chemicals or pathogens.
- Some processes, such as reverse osmosis, create wastewater, which can be inefficient and increase water consumption.
- Filter systems require maintenance and replacement, which can be costly and time-consuming over time.
- Quality varies between different purification methods, meaning that not all purified water is equally clean or free from contaminants.
- Purified water may retain trace contaminants that distillation would remove, potentially compromising purity in certain cases.
Health and Safety Insights: Distilled Water vs Purified Water
Both distilled water and purified water are safe to drink when properly processed. But which option supports your health better?
Can Humans Drink Distilled Water?
Yes, humans can drink distilled water safely. The concern isn't immediate harm but long-term mineral deficiency. Since distilled water is created by removing everything, including beneficial minerals like calcium and magnesium, your diet must provide these nutrients.
Health Considerations by Age Group
Children and Infants:
- Distilled water is used for baby formula because it's completely pure
- Reduces risk of waterborne illness in developing immune systems
- Parents should ensure babies get minerals from other sources
Elderly Adults:
- May prefer to drink purified water for better taste
- Benefit from trace minerals that some purification methods preserve
- Easier to stay hydrated when water tastes better
Immunocompromised Individuals:
- Distilled water is often recommended for those with weakened immune systems
- Provides absolute protection from waterborne pathogens
- Medical professionals frequently suggest this option during treatment
Is it Good to Drink Purified Water?
Purified water is generally an excellent choice for daily hydration. It provides clean drinking water while often retaining beneficial minerals. The benefits of purified water include:
- Removal of harmful contaminants
- Better taste than heavily processed alternatives
- Potential mineral content supporting health
- More environmentally friendly production
Taste, Usability, and Appliance Benefits
The difference between distilled water vs purified water becomes obvious when you taste them. Distilled water tastes flat because it lacks the minerals that give water its natural flavor. On the other hand, purified water typically tastes much better because it keeps some of these flavor-enhancing minerals, making it a more enjoyable option for everyday drinking.
Coffee and Tea Preparation
Coffee enthusiasts often find that purified water makes better-tasting beverages. The trace minerals enhance flavor extraction, allowing for a richer, more aromatic brew. In contrast, completely mineral-free distilled water can make drinks taste dull, as the lack of minerals diminishes the subtle flavors that are crucial for a well-balanced cup of coffee or tea.
Cooking Applications
Most chefs recommend purified water for cooking because it's clean water that won't interfere with recipes while adding subtle mineral complexity to foods. The minerals retained in purified water can enhance the natural flavors of ingredients, ensuring that dishes taste more vibrant. In contrast, distilled water, being mineral-free, may result in less flavorful outcomes, especially in recipes where water plays a key role in flavor development.
Appliance Protection
Distilled water is used in steam irons, humidifiers, and CPAP machines because it prevents mineral buildup that can damage equipment. The pure water won't leave white residue or scale deposits, which can clog or wear down the internal components. This helps extend the lifespan of appliances and ensures they operate efficiently without the need for frequent cleaning or maintenance.
Environmental and Cost Comparison
Energy Use and Environmental Impact
While both methods aim to improve water quality, distilled water vs purified water reveals a notable difference in energy use and environmental impact. Distilled water requires significant energy because boiling water to create steam is an energy-intensive process. This makes it less environmentally friendly for large-scale production, as it leads to higher carbon emissions and resource consumption. Additionally, the process generates more waste heat, further increasing the overall environmental impact.
Purified water methods vary in environmental impact:
- Reverse osmosis uses less energy but creates wastewater
- Carbon filtration is very efficient with minimal waste
- Ion exchange requires periodic regeneration but uses less energy overall
Cost Analysis
| Water Type | Home System Cost | Ongoing Expenses | Bottled Water Cost |
| Distilled | $100-300 for countertop unit | High electricity costs | $1-2 per gallon |
| Purified | $150-500 for RO system | Filter replacements | $0.50-1.50 per gallon |
Purified water systems, incorporating a water filter, often provide better long-term value because they're more energy-efficient and produce water faster than distillation units.
Regulations and Standards
The EPA regulates more than 90 contaminants in public drinking water. Both distilled and purified water must meet these standards, but they often exceed them significantly.
Key Regulatory Points:
- Purified water is water that meets specific purity standards regardless of method
- Distilled water is actually a type of purified water under regulatory definitions
- Bottled water must meet FDA standards that are equivalent to EPA tap water standards
- International standards from WHO provide similar guidelines globally
Choosing the Right Water for Your Needs
Now that we’ve understood the differences between distilled water vs purified water, how should we choose? Consider the following factors:
For Daily Drinking:
Purified water is typically the best type of water for regular consumption because it balances purity with taste and potential mineral benefits. It ensures you're hydrated while still providing some essential minerals that support your overall health.
For Medical Uses:
Distilled water provides the ultimate purity needed for medical equipment, wound care, and situations where absolute cleanliness matters. Its lack of minerals and contaminants makes it ideal for preventing any interference with medical procedures or treatments.
For Appliances:
Use distilled water in steam-producing appliances, like irons and humidifiers, to prevent mineral buildup and extend equipment life. The absence of minerals ensures that these devices stay clean and function optimally without the need for frequent maintenance.
For Babies:
Many pediatricians recommend distilled water for formula preparation, especially in areas with questionable water quality. Since it’s free from contaminants and harmful minerals, it ensures that babies are only exposed to the cleanest, safest water, with parents advised to provide necessary minerals through diet or supplements.
Is Bottled Water Distilled?
Most bottled water is not distilled. Common types of bottled water include:
- Spring water from natural sources
- Purified bottled water using various filtration methods
- Mineral water with naturally occurring minerals
- Alkaline water with adjusted pH levels
How Do I Know if My Bottled Water is Distilled?
Check the label for these terms:
- "Distilled"
- "Steam distilled"
- "Vapor distilled"
If the label says "purified," "filtered," or "reverse osmosis," it's purified water but not distilled.
Can I Substitute Distilled Water with Purified Water?
Is purified water the same as distilled water? Not exactly, but you can often substitute one for the other:
Safe substitutions:
- Daily drinking: Purified water is often preferred because it tastes better due to the minerals it retains, enhancing flavor.
- Cooking and food preparation: Purified water works well in cooking, as the subtle minerals can improve the taste and texture of dishes.
- Most household uses: Purified water is fine for general uses like filling a water pitcher, washing, or watering plants.
Avoid substitutions:
- Medical equipment requiring absolute purity: Distilled water is necessary for medical devices, as it is free from all contaminants and minerals.
- Laboratory experiments: For precise scientific work, distilled water is crucial to avoid interference from any trace minerals or impurities.
- Steam appliances where minerals cause problems: Distilled water should be used in humidifiers, irons, and other steam-producing devices to prevent mineral buildup and equipment damage.
- Baby formula: While distilled water is generally recommended for formula preparation, always consult your pediatrician first to ensure it's the safest option for your baby.
Frequently Asked Questions
1. Which is Better: Purified or Distilled Water?
Compared with purified water and distilled water, which one is better depends mainly on the specific use.
For daily drinking, purified water is more suitable. It is clean and safe, and retains beneficial trace minerals such as calcium and magnesium. These minerals help hydrate the body and are important for health. Additionally, because of these minerals, purified water has a better taste, with a natural sweetness. It is produced through methods such as reverse osmosis, carbon filtration, and ion exchange. These methods effectively remove contaminants without stripping away essential elements from the water.
For specialized uses requiring exceptional water purity, distilled water is more suitable. Distillation removes nearly all minerals and contaminants, making it a popular choice in medical settings, laboratory experiments, and some household appliances. In areas where water quality is uncertain, distilled water is also safe for preparing infant formula. Using distilled water for devices like steam irons, humidifiers, and continuous positive airway pressure machines can prevent mineral buildup and damage.
In general, for everyday drinking, purified water is a better choice due to its superior taste and health benefits. However, when extremely high purity is required for special applications, distilled water is the optimal option.
2. Can I Substitute Distilled Water with Purified Water?
In most everyday situations, purified water can be used as a substitute for distilled water. For example, when it comes to daily drinking, purified water is clean and safe, and it retains beneficial trace minerals such as calcium and magnesium. This allows it to hydrate the body while providing some nutrients. When cleaning, using purified water to wipe furniture and clean items reduces the residue of impurities in the water, enhancing cleaning effectiveness.
However, in some special cases, distilled water cannot be replaced by purified water. For example, the cleaning and operation of medical equipment require extremely high water purity. Any mineral residues could affect the equipment's precision or even interfere with the treatment process, so distilled water must be used in such cases. In laboratories, many experiments require an absolutely pure environment. Any minerals or impurities in the water could cause experimental results to deviate, so distilled water is the preferred choice for laboratories.
For steam-based devices like humidifiers and irons, prolonged use of purified water containing minerals can cause mineral buildup inside the equipment, affecting its lifespan and efficiency. Distilled water, which contains no minerals, effectively prevents such issues.
3. When Should I Use Distilled Water?
Distilled water is primarily used in situations where extremely high water purity is required or where mineral deposits could cause damage.
When preparing infant formula, especially in areas where tap water quality is unreliable, distilled water is recommended. This ensures that the water is free of harmful contaminants, providing a safer dietary environment for infants.
Medical device sterilization also relies on distilled water. From sterilizing medical instruments to cleaning wounds, its pure and impurity-free nature ensures medical safety and minimizes the risk of infection.
Steam irons, humidifiers, continuous positive airway pressure (CPAP) machines, and other steam-based devices can effectively prevent mineral deposits by using distilled water. Once these deposits form, they may clog the device system, impair normal operation, or even shorten the device's lifespan. Distilled water helps avoid such issues.
Distilled water is also an appropriate choice for charging car batteries. When maintaining a car, adding distilled water to the battery prevents electrode plate scaling and keeps the battery in optimal condition.
Additionally, in scientific experiments, laboratory work, and any other scenarios where even trace amounts of minerals could affect results or functionality, distilled water plays a crucial role in meeting stringent purity requirements. In summary, when the components in ordinary water may cause issues, it's time to switch to distilled water.
4. Is Drinking Purified Water Safe Long-term?
Drinking purified water regularly is safe and often highly beneficial to health. It differs significantly from distilled water, which removes all minerals. Most purified water treatment processes intentionally retain essential minerals, such as calcium and magnesium, that are essential for human health. The human body truly cannot do without these seemingly trace amounts of minerals. Calcium not only strengthens bones but also forms the foundation for strong teeth. Magnesium participates in hundreds of metabolic reactions in the body. These minerals not only help us absorb water better but also continuously deliver essential nutrients to the body, maintaining normal life.
Purified water production undergoes a variety of rigorous filtration methods, which effectively remove harmful contaminants such as chlorine, bacteria, and heavy metals, resulting in a cleaner water. As long as purified water is properly treated and meets safety standards, it is an ideal long-term hydration option.
Compared to untreated tap water, purified water offers an additional layer of safety. Furthermore, it avoids the mineral loss associated with distilled water. Therefore, from the perspective of safety and health, drinking qualified purified water for a long time is very reliable.
5. How Can I Tell if Bottled Water is Actually Distilled?
To determine whether bottled water has truly undergone distillation, the most direct method is to examine the label on the bottle. If the label clearly states terms such as “distilled,” “steam distilled,” or “gas phase distilled,” it indicates that the water has been processed through distillation. The distillation process involves boiling water and condensing the steam into liquid. This completely removes impurities and minerals from the water, resulting in a highly pure water.
If the label states “pure,” “filtered,” or “reverse osmosis,” it is not distilled water. Such water uses other filtration methods, which can remove most contaminants but may still leave trace minerals.
Ultimately, choosing between distilled water and purified water depends on your specific needs. For most people, purified water is a good choice, as it strikes a good balance between purity, taste, and health benefits. It effectively removes harmful contaminants while retaining beneficial minerals.
Distilled water, however, is highly pure and is more popular in certain specialized applications, such as equipment cleaning and laboratory procedures in the medical field, as well as in appliances where mineral buildup must be avoided. Therefore, when choosing, you can decide based on your health needs, taste preferences and specific uses.
References
- United States Environmental Protection Agency. (2023). National Primary Drinking Water Regulations. https://www.epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations