Reverse Osmosis Vs Deionized Water: Which One Is Better?

Water is essential to maintain an individual’s body’s proper functioning and health.

Because of industrialization and excessive pollution in today’s world, people use water filters to purify the water before consuming it. Reverse osmosis and deionized water filtration are the two most common and widely used equipment for filtering water.

In this article, we will discuss both types of equipment in detail. These equipment serve very different purposes and depend on the water problem you face at home.

So, please read it carefully! It will help you get a clear idea of what equipment to invest in or buy.

What is Reverse Osmosis?

What is Reverse Osmosis?

Reverse osmosis, or RO, is one of the most popular separation techniques for water purification, removing chemicals and contaminants from the water.

This technique uses a semipermeable membrane, effectively removing dissolved chemical particles and microorganisms from the water body.

The reverse osmosis equipment only works at high pressure and depends on salt concentration.

Reverse osmosis water filtration is a cost-effective process and is one of the most popular methods available in the market. It is widely used equipment in small businesses and homes because it is budget-friendly and very effective to filter water.

This equipment is easy to install in a residential area (it only takes tiny space in the kitchen or drinking area) and requires less maintenance. It doesn’t influence the taste of water and is environment-friendly.

Get Minerals From Food

The Reverse Osmosis process completely removes the minerals because most of them are inorganic and not digestible by the human body. It removes all the minerals, which is why we need to maintain a diet and take the minerals from the food.

Reverse osmosis ‌removes the components like detergents, nitrates, sulfates, chloramine, chlorine, pesticides, and lead. The equipment has additional carbon and sediment filters, which help in filtration.

Most brands ‌use 4 to 5-stage processes to enhance the water’s quality, make it delicious, and give the water a clean taste.

What is Deionized Water?

What is Deionized Water?

Deionized water can also be called demineralized, DM, or DI water.

This water can be defined as water that does not have most of the ions that are generally present in water. The deionization process removes these ions.

These ions are considered an essential component of the water that influences the taste of the water. Calcium, copper, iron, and sodium are the most common ions found in regular tap water.

The equipment uses charged resin bead, which attracts the positively or negatively charged minerals from the water.

Whenever the natural water passes through this equipment, the minerals get attached to the raisins, thus allowing clean water. Different raisins are used according to the needs and demands of the consumers.

The strong acid cation and weak acid cation are the two types of cation resins, while the strong base anion and weak base anion are the two types of anion resins.

What Reverse Osmosis and Deionized water do?

Both water forms excel at removing pollutants and minerals from water. Depending on the filtration system, these procedures are effective when removing harmful contaminants from the water.

Here we have discussed what exactly reverse osmosis and deionized water do in detail. Let us take a look below.

Reverse Osmosis Removes the Minerals

The Reverse Osmosis process completely removes the minerals because most are inorganic and not digestible by the human body.

Reverse osmosis is most suitable for removing salt and other contaminants from the water. Additionally, it eliminates minerals from the water body that are thought to be healthy for humans, including fluoride, magnesium, calcium, and iron.

You can use reverse osmosis water as it is more suitable for cooking and drinking.

Also, Reverse osmosis removes the components like detergents, nitrates, sulfates, chloramine, chlorine, pesticides, and lead. The equipment has additional carbon and sediment filters, which help in filtration.

Be mindful that it removes all the minerals, so we must maintain a diet and take them from the food.

Deionized Water Removes Calcium, and Magnesium

Deionized water is entirely safe to drink, but one should not consume it in very high amounts or consider the deionized form of water as the primary form of drinking water in their daily routine.

This can highly impact the health of an individual.

The main reason is that calcium and magnesium are the two most essential minerals we get from water and are required by the body for growth and development.

The deionized water does not comprise these minerals. Even if you depend on deionized water, you must rely on calcium or magnesium supplements or maintain a proper diet.

Deionization removes oxygen and salt from the water and also removes the minerals from the water, leaving all impurities behind.

Thus, we will never recommend you make the deionized form of water the primary source.

Moreover, deionized water is most suitable in pharmaceuticals, power plants, food processing, electronics manufacturing, cosmetics, cooling process machinery, and medical laboratory practices.

If you are using deionized water in cooking, the presence of harmful ions and minerals will lead to a sour taste.

Reverse Osmosis Vs Deionized Water: The Main Difference

To entirely understand the main difference between these two filtration methods is that reverse osmosis uses a semipermeable membrane to purify water.

In deionization, Ion exchange is used to replace minerals and impurities.

Which means the only major difference is the level of purity.

Reverse osmosis water still has salts and oxygen in it, despite being safe to drink. Deionized water does not affect dissolved solids; however, it does remove salts and oxygen from the water.

Which One is Better? Reverse Osmosis or Deionized Water?

The advantage of using deionized water is that it acts as a water softener and removes contaminants.

And a reverse osmosis system can also filter bacteria, viruses, insecticides, and herbicides, among other contaminants.

RO and DI are equal when it comes to removing contaminants from water. However, the reverse osmosis process removes all the bacteria and viruses, but deionized water can’t.

Which one is better truly depends on your usage of these waters and where.

Frequently Asked Questions

Which water filter (deionized or reverse osmosis filter) is much more beneficial?

Suppose the water in your area is highly contaminated. In that case, you should opt for reverse osmosis equipment, while if your problem is only with the ions in the water, then you should buy a deionized system.
According to the report, the reverse osmosis equipment removes around 90 to 99% of the contaminants in the water, while deionized only removes the minerals or the ions from the water.

Can I rely entirely on a particular water filter?

Natural water consists of calcium and magnesium, the two most essential nutrients for the development of the human body.
The reverse osmosis filters or the deionized water completely remove certain nutrients or minerals required for human growth; thus, we will never recommend you rely on it entirely.
Even if you are relying completely on it, make sure you are taking a proper diet rich in these minerals and able to fulfill your body’s requirements.

Besides the municipality department, do I also need to consult the doctor before buying any filters?

For a healthy individual, it is not necessary to consult a doctor. But a person whose body is highly deficient in magnesium, calcium, or other minerals needs to consult a doctor before buying anything.
If you visit a local doctor, the doctor will suggest a different mechanism by which you can filter the water.
If you are visiting any other doctor who does not know about water quality in your area, you should tell them about your problem so they can look into it.

Is bottled water in the market better than deionized water and RO water?

Bottled water in the market is not always purified or does not always provide enough nutrients to the body. Several brands in the market come with different objectives.
You need to read the component carefully whenever you buy bottled water because they are all different and are meant to provide distinct advantages to the human body.
Apart from this, bottled water is not environmentally friendly because of the use of excessive plastic to pack or supply them in the market.
Furthermore, the rate of microplastic accumulation in the body also increases. So it is better to avoid bottled water as much as possible.


Reverse osmosis and deionized filtration equipment have different purposes. However both RO and DI are nearly comparable.

On the other hand, the reverse osmosis process might get rid of viruses and germs that deionization cannot.

As a water softener as well as a purifier, deionizing is the opposite. Both are excellent for cleaning since they don’t leave streaky mineral deposits.

They function well in humidifiers and boilers and are suitable for a variety of industrial settings, including aquariums, manufacturing, and the cosmetics and beauty industries.

As demineralized water, both types of water are comparable to one another in this way. While it may seem that different cleansing methods are intended to achieve this, healthy human bodies need a variety of components and minerals.

Check Out These Article
Sterile Water Vs Distilled Water
Alkaline Water Vs Purified Water
Well Water Vs City Water
Reverse Osmosis Vs Water Softener
Cold Water Vs Warm Water