Most of us know that drinking plenty of water is essential to staying healthy. However, it’s easy to get confused about which type of water is best to drink.
In this article, we examine the differences between purified and distilled water to help you understand which is the best option.
📌 Key Takeaways:
- Distilled water is water that has been treated by a distiller unit.
- Purified water is water that is completely free from all impurities. Distilled water is a type of purified water.
- The biggest difference between distilled water and purified water is that distilled water can only be produced by distillation, while there are numerous ways to achieve purified water.
Table of Contents
🆚 Distilled Water vs Purified Water Overview
Just looking for a quick comparison of distilled water vs purified water?
Here are the main differences between the two water types:
- Treatment process. Distilled water is produced by evaporating and condensing water (distillation), while purified water is made by a number of methods, such as reverse osmosis and distillation. Some people also consider UV treatment and deionization as methods of purifying water.
- Water quality. Distilled water is virtually free from all contaminants, although distillation doesn’t remove all chemicals or VOCs. Purified water may be free from all impurities or free from microbiological contaminants.
- Water taste and smell. Distilled water tastes slightly “flat” compared to spring water or even normal tap water due to its lack of minerals. Purified water that’s mineral-free has a similar taste. If water has just been purified to kill microorganisms, its taste won’t have changed.
🚰 What is Purified Water?
The actual definition of purified water is this: “water that has had all its minerals, salts, chemicals, metals, and other contaminants removed, making it pure (impurity-free)”.
However, “purification” also commonly refers to the removal or killing of microorganisms in water, so purified water can also be classed as “water that is microbiologically safe to drink”.
Common physical, chemical, and biological contaminants that are removed through purification include:
- Heavy metals (lead, copper, etc.)
- Viruses, parasites & pathologic bacteria
- Pesticides & herbicides
Tap water is technically safe to drink because water utilities are legally required to comply with Environmental Protection Agency (EPA) Standards. However, many people choose to purify their water to improve its taste, quality, safety, or health properties.
For folks who use a private well supply, it’s often the case that a water purification system is essential.
⚗️ What is Distilled Water?
Distilled water is a form of purified water.
To make distilled water, the process of distillation is used. Water is heated to boiling point until it evaporates into steam. Most of the impurities found in water are unable to vaporize, so they’re left behind in the boiling chamber.
Then, the steam is then collected and condensed, turning it back into extremely pure water.
Distillation takes place in a distiller. There are at-home water distillers available that are designed to sit on your kitchen countertop. It takes about 5 hours to produce a 1-gallon batch of purified water in a distiller.
Related: What’s the difference between boiled water and distilled water?
📝 Distilled Vs Purified Water: Key Differences
Now we know the definition of distilled and purified water, let’s look at their key differences.
How It’s Made
The most obvious difference between distilled water vs purified water is how the water is made.
Distilled water is made using just one process: water distillation. The distillation process involves boiling and evaporating water, then condensing it into a separate container.
You can distill water at home using a distiller machine, or buy distilled bottled water from the store.
Purified tap water, on the other hand, is made with a variety of purification methods, including reverse osmosis filtration systems and distillation. Deionization and UV treatment are also commonly classed as water purification. Some folks also say that boiling water purifies it because it’s capable of removing microorganisms.
Numerous water purification systems are available for at-home use. You can also buy purified bottled water.
⚖️ Summary: Distilled water is made in a distiller, while purified water is made by one of several purification methods.
What It Contains
Distilled water is free from all soluble minerals, most chemicals, microorganisms, and heavy metals like lead and arsenic.
Distilled water may contain traces of chemicals and volatile organic compounds (found in many tap water supplies). Many volatile organic compounds and chemicals are able to vaporize and condense with water, hence why they’re sometimes present in distilled water.
Purified water in the literal sense is essentially pure water. That means it contains no contaminants, or tiny trace levels of contaminants, because most impurities (up to 99.99%) have been removed. Distilled water is a type of purified water for that reason.
Water that has been purified with other “purification” techniques, like a UV light filter or deionization, may still contain contaminants but is safe to drink from a microbiological perspective (in the case of UV purified water) or is free from all dissolved ions (in the case of deionized purified water).
⚖️ Summary: Distilled water contains almost no contaminants, but may contain traces of chemicals and VOCs. Purified water might be almost completely pure and contaminant-free, or it might contain some contaminants but no microorganisms or ions, depending on the purification method.
Related: Distillation and deionization: 2023 comparison
How It’s Used
Distilled water isn’t only used at medical facilities and labs. At home, distilled water is predominantly used in the following ways:
- In aquariums
- In steam irons
- To water plants
- In car cooling systems
- In continuous positive airway pressure (CPAP) machines for sleep apnea
Some people also drink distilled water, and it’s safe to do so. However, many folks don’t enjoy the plain, “flat” taste of distilled water, so it’s not a super popular choice for drinking.
Purified water can be used in the same ways as distilled water, depending on the extent of the purification. Water that has only had its microorganisms killed or removed will be unsuitable for steam irons, car cooling systems, etc. because it still contains natural minerals that may damage these appliances.
Many people drink purified water. Some water purification systems, such as reverse osmosis systems, come with optional remineralizing stages, improving the taste and health properties of the purified water.
⚖️ Verdict: Distilled water and purified water have similar uses, but (depending on the purification method), some types of purified water may be more enjoyable to drink.
📊 Pros & Cons of Purified Water
Now we know the key differences between distilled and purified water, let’s consider the pros and cons of both of them – starting with purified water.
Benefits of Purified Water
- Contaminant-free. Purification techniques, and especially reverse osmosis, remove up to 99.9% of all total dissolved solids in drinking water, making it almost completely pure. If you’re concerned about the health implications of drinking water, pure water is far cleaner and safer for drinking than standard tap water.
- Remineralization. Some purification units (most commonly reverse osmosis filters) come with a built-in remineralization filter, which adds healthy calcium and magnesium minerals back into water.
- Immediate results. Many purification techniques are incredibly speedy and can purify water within minutes.
Disadvantages of Purified Water
- Can be costly. If you’re considering purchasing a water filter or reverse osmosis system, you’ll need to factor in costs for regular filter changes in addition to the upfront cost of the system.
- Installation. Drinking water purifiers are complex by nature. Although most systems are designed for at-home set-up and come partially assembled, some folks might find the installation difficult. However, some purifiers are easy to set up, such as water distillers.
- Removes healthy minerals from water. Sometimes the beneficial minerals are removed with the bad impurities, depending on how water is purified.
- Requires high water pressure. Many water purifiers will lose their efficiency in producing pure tap water if the incoming water pressure is too low.
📊 Pros & Cons of Distilled Water
Now let’s look at the pros and cons of drinking distilled water.
Benefits of Distilled Water
- Completely contaminant-free water. Distillation is highly efficient at the removal of all impurities from contaminated water, vastly reducing your risk of consuming any harmful chemicals. Those with weakened immune systems may benefit particularly from the purest water achievable.
- Lower cost. Compared to other methods of water purification, water distillers are often cheaper to buy upfront and don’t require frequent filter changes.
- Simple installation. Most distillers come almost completely assembled. When you’re ready to drink distilled water, just plug the machine in and switch it on.
You might also like our article about the 10 best water distillers
Disadvantages of Distilled Water
- Lengthy process. The distillation process is incredibly long – much longer than any other method used to purify water. Water condenses literally droplet by droplet. It takes hours to distill just 1 gallon of drinking water.
- Consumes a high amount of energy. Water in the distiller needs to be boiled until there’s nothing left in the boiling chamber, which takes a lot of energy. Your electricity bill will increase if you use a water distiller every day.
- Removes healthy minerals from water. Water distillation removes minerals like potassium, calcium and magnesium. Water is more “hungry” in this state and may be more susceptible to leaching from plastic and metal, so it’s not recommended to store distilled water long after it’s produced – especially not in plastic bottles. If you don’t enjoy drinking distilled water, you’ll need to purchase mineral drops or a remineralization filter. Plus, folks who drink only distilled water should make sure they’re getting enough minerals elsewhere in their diets.
- Requires regular upkeep. After the distillation process, a variety of drinking water contaminants are left behind in the boiling chamber, including metals, limescale, chemicals, and potentially even harmful bacteria and other microorganisms. You need to clean a distiller regularly to prevent permanent staining.
Related: Drinking Distilled Water: Is it Safe?
🤔 Is Purified or Distilled Water Better?
There’s virtually no difference between distilled water and water produced by a purification method. The exact differences between the two water types depend on the method of water purification.
Which water type is best: distilled or purified drinking water? It just depends on your preferences when it comes to purified water production.
Distillation is a very long process, so this method of purification might not be for everyone. But for some folks, especially those who are retired or work from home, it may be no issue to switch on the distiller every morning and enjoy distilled water as it’s gradually produced throughout the day.
However, purified water can be produced more conveniently, such as with a reverse osmosis filtration system, which purifies tap water within a matter of minutes. Plus, it’s easier to remineralize your purified water with other purification options.
📌 Note that you might not even need completely pure water. If you just want to improve the taste of your drinking water or remove contaminants commonly found in municipal water, you might be fine using more basic filtration methods, like under sink and countertop water filters.
In our opinion, purified water is better than distilled water because it can be faster to produce and you have more purification options to choose between.
📑 Final Word
Ultimately, regardless of whether you want to buy a water distiller or another type of purifier, make sure that it’s tested to, or certified by, Standards set by a trusted third-party organization, like NSF International or the Water Quality Association.
You can trust that a product with certification performs exactly how the manufacturer claims it does.
Also check customer reviews and see what experts in the water industry have to say about a product. You want to make sure that your investment is totally worth it.