Spoiler alert, distilled water is a type of purified water 🙂
But does it mean that they are the same? Well, not exactly.
We spent hours researching this topic to give you the most complete and accurate information about purified water and distilled water, backed up by trustful sources.
Keep reading to find the full explanation about distilled vs purified water, what is distilled water, what is purified water, how they differ, if they are good to drink, their pros & cons, and a chart that summarizes all the relevant information.
What is the main difference between distilled water and purified water?
There are different processes to purify water, and distillation is one of them, so in reality, distilled water is a type of purified water.
The big difference is that in the process of distillation, chemicals, contaminants, minerals, and other organic materials are removed, while purified water doesn’t have all the important minerals removed – purified water doesn’t have chemicals and contaminants, but it still has some minerals.
Why drink distilled or purified water instead of tap water or bottled water?
Distilled water and purified water are similar, and both are healthy choices for you. Tap water may not always be safe to drink.
Depending on where you live, the quality of tap water may not be great – in some areas, heavy metals (like lead and copper) may be found in public water, and prolonged exposure may cause stomach and brain health issues.
That being said, the Environmental Protection Agency (EPA) [1] sets the national legal limits on over 90 contaminants in drinking water, and each state can define its own standards as long as they comply with EPA’s requirements. So, most sources of public drinking water are regulated and should be safe to drink.
Distilled Water
In the distillation process, to get distilled water, water is boiled and the generated steam is collected, and then cooled down to get the pure water back but without contaminants, bacteria, metals, inorganic minerals, etc.
This happens because the boiling point of water is 212 ºF (100 ºC), and the boiling point of most of the contaminants is higher than this – so the water turns into steam but the contaminants are left behind.
Can you drink distilled water?
Yes, you can! Because it removed contaminants chemicals and inorganic minerals, is a healthy choice for you.
Some people find its flavor a bit more flat than tap water, but that is because some minerals have been removed.
A common question is if it is ok for a baby to drink distilled water, and the answer is also yes. Trustful sources [2, 3] recommend the use of distilled water to prepare baby formula because it doesn’t have not only contaminants but also fluoride, to avoid fluorosis [4].
Common uses for distilled water
Distilled water has a lot of potential uses, such as:
Drink: As mentioned above, it’s free of contaminants and other harmful products, so it is a good choice to drink, and even more beneficial for people with weak immune systems that shouldn’t be exposed to impurities and contaminants (we are not doctors, so if you have an immune system disease, please check with your doctor first).
Steam Irons: Because distilled water doesn’t have minerals, it won’t clog your iron steam holes
Automobiles: In car cooling systems to prevent mineral build-up
Aquariums: You just need to be careful and add sea mineral supplements to your fish diet, because distilled water doesn’t have them
Medical tools and procedures:
- Used to clean equipment because it helps to avoid infections
- Also, kidney dialysis machines use distilled water
- Most manufacturers of CPAP (continuous positive airway pressure) machines used for sleep apnea recommend the use of distilled water to prolong the life of the machine
Neti pots: FDA recommends the use of distilled water when rinsing your sinuses with Neti Pots [5]
Hair wash: Because some tap water components, like chlorine or fluoride, may dull your hair, some people use distilled water to wash their hair
Coffee: Some coffee purists prefer to use distilled water to have a more pure-tasting coffee cup
Baby formula
Watering plants
Lab experiments
Cosmetics
Pros & Cons of distilled water
Pros:
- No contaminants, chemicals, and bacteria: The distillation process removes harmful contaminants from the water
- No chlorine: Tap water has chlorine, which may affect the water taste. Distilled water doesn’t have chlorine, so drinking it will reduce your chlorine exposure and remove the chlorine taste
- Typically is safer to drink than tap water: Even if most sources of public drinking water are regulated, they still may have some contaminants and organic materials. Using distilled water reduce your exposure to these components
- Good choice for people with weak immune systems: For example, people with cancer or HIV should avoid contact with impurities that tap water may have, so distilled water is a good option
Cons:
- Flat taste: Some people found distilled taste flat comparing with bottled or tap water. If this is a problem for you, it is an easy one to solve – just add some lemon juice to your water
- Lack of important minerals (like calcium and magnesium): The distillation process removes harmful contaminants, but also some minerals that are good for you. Drinking water with low calcium and magnesium levels has been associated with some health issues, like heart disease or fractures. That being said, is important to understand that with a well-balanced diet this should not be a problem, and in reality, tap water is not a major source of minerals for humans
- No fluoride: Public drinking sources usually had fluoride in their water, to help to improve dental health. Removing fluoride may increase the risk of cavities
- Storage: Distilled water can pull in minerals from different materials, so storing may be an issue depending on the containers you use to do it
- Cost/energy consumption: The distillation process uses a lot of energy to boil the water and then cooling it down, so it’s not a great choice in terms of energy conservation, and it will be more costly to get than tap water
Purified Water
Is important to understand that purified water is not the same as filtered water – purified water is water with almost zero impurities. Technically, water can be legally classified as purified water if it has less than 10 parts-per-million (PPM) of impurities (like contaminants or chemicals) in it, so 99.999% pure.
Filtered water is also subject to a process of filtration to make it purer, but purified water goes through additional processes to make sure it reaches the defined threshold of purity.
Water purification processes
There are different water purification processes designed to remove water impurities, and in some cases, more than one of these processes is combined to get purified water. The most common water purification processes are:
Distillation (covered above)
Reverse Osmosis:
Is considered one of the best water purification systems, because it’s really good at purifying water but also because it’s much better at energy consumption than the distillation process.
This process consists of pushing water through a semipermeable membrane that filters out particles larger than water molecules, effectively removing impurities and contaminants.
Some Reverse Osmosis systems come with a carbon filter that helps to remove some volatile organic compounds (VOCs) that are not directly removed by reverse osmosis.
Deionization:
This process is sometimes combined with other methods because while is extremely effective at removing mineral ions from water, is not as effective at removing organic molecules and bacteria.
In this process ion-exchange resin filter are used to exchange hydroxide ions for dissolved minerals, so is a great method to deal with hard water, which is rich in minerals like calcium and magnesium.
Ultraviolet (UV) light:
In this process UV light is used to disinfect the water, removing microorganisms, bacteria, and viruses.
Coagulation and flocculation:
Inorganic coagulants are added to the water to bind with other particles in the water forming alter particles (flocs), that can then be filtered out of the water.
Sedimentation:
The larger and heavier particles will settle at the bottom of water supply tanks so that the water can then be extracted without these particles.
Disinfection:
In this water purification process, disinfectant chemicals, like chlorine, are added to the water. The objective is to kill any micro-organisms, bacteria, or viruses.
Impurities removed with purification
It is important to understand that a lot of bad stuff is removed to be able to get purified water. Different impurities are removed from water through water purification processes, like:
- Heavy metals, such as copper and lead, are really bad for your health [6]
- Chlorine – some water purification systems remove this component, which is usually added to public water sources to work as a disinfectant, but in excess may cause health issues, like certain types of cancers [7]
- Chemicals
- Bacteria
- Parasites
- Algae
- Fungi
Can you drink purified water?
Absolutely yes! Purified water is one of the healthiest types of water that you can drink.
While tap water is typically safe it still may have some contaminants and purified has less than 10 PPM of impurities, so it’s virtually free of contaminants and chemicals.
It may not have some nutrients that you may found in tap water, but in fact, this is only a tiny portion of your needs, so if you have a balanced diet this won’t matter.
Pros & Cons of purified water
While there are a lot of benefits of drinking purified water, some drawbacks also exist. So you should be aware of the pros & cons of purified water:
Pros:
- More pure water: As the name indicates, this type of water is purer than other water types
- No unpleasant taste/flavor: Chemicals, metals, and organic materials may give a weird taste to the water – because pure water doesn’t have anything of this, it has a more clean and fresh taste
- No hard metals: Heavy metals such as lead and copper, which are toxic for you, are removed during water purification processes
- No bacteria: Removal of bacteria, that may cause you different health issues, is extremely effective during water purification
- Better skin: Removing impurities from the water, and from your body, will lead you to a better skin health
- No contaminants: Purified water is virtually free of contaminants (but not 100%)
- No chemicals
Cons:
- No fluoride: While this is not a big issue because you can and should compensate in other ways, purified water doesn’t have fluoride that is added to the water public supplies in some countries to help improve dental health and reduce tooth decay. Also, excessive fluoride levels can be harmful to your brain and nerve cells, as some studies indicate a link between memory and cognitive decline and long-term exposure to high levels of fluoride [8, 9]
- Not complete removal of contaminants: Depending on the water purification process used, while most of the contaminants are removed, some may still be found
- Cost: Compared with tap water that is free, the cost of purified water may be a drawback for you. If you decide to install a home purification system or purchase purified bottled water, both options have costs that you should take into consideration
- System maintenance: If you use a water purification system it should be regularly maintained, to avoid contaminants that can build up in used filters to get into your drinking water
- Waste: Not an issue if you use a home system, but if you purchase bottles of purified water you are causing a lot of waste that is damaging to the environment
What Next?
While tap water is not necessarily bad, if you are looking for clean and healthy water, purified water is the right choice. Distilled water is also a good choice, but make sure you have a balanced diet, in that case, to make sure you get all the right minerals.
Most water filtration systems use one or more water purification processes, so if you are interested in clean water, read more about water purification processes like reverse osmosis or about water filtration systems in our guides.
