Is Rain Water Distilled? How Pure is Distilled Water?

Rainwater is distilled as long as it doesn’t collect any substances from the environment. Distillation makes the purest form of water and replicates the process that makes rain, so rainwater remains distilled until it contacts the environment.

Collecting environmental contaminants and minerals lowers the purity of rainwater, so it is no longer distilled.

There’s a myth that rainwater can’t be pure. While the sentence might ring true sometimes, not many know that pure rainwater exists. We all know distilled water is the purest form of water, but did you know rainwater could be equally pure?

The process that makes rain is quite similar to the one that makes distilled water, so many will ask:

Is rainwater distilled?

Is Rain Water Distilled? How Pure is Distilled Water?

The brief answer is: rainwater is distilled water before it becomes rainfall.

Allow us to elaborate. Distilled water contains no minerals or contaminants, so it’s extremely pure. Rainwater also contains no minerals and contaminants when it’s created, so it is technically distilled water.

However,  rainwater can pick up minerals and contaminants from the air when it falls, so it loses its purity and no longer remains distilled water.

It isn’t as complex as it sounds, but let’s go over distilled water and rainwater in more detail to understand.

Key Takeaways

Here’s a quick review if you’re in a hurry:

  • Distillation purifies and removes all nutrients, including minerals, to create distilled water.
  • Distilled water is the purest form because it contains nothing but water molecules.
  • Distillation is the same process that makes rain naturally, so rainwater is distilled as soon as it is created
  • Rainwater collects minerals and environmental contaminants from the air and ground during rainfall, so it no longer remains distilled
  • Distilled water isn’t the healthiest form since it contains no minerals; rainwater is much healthier because it has some essential minerals and a higher oxygen count

Is Rain Water Distilled?

The natural process that makes rain is basically distillation, so rainwater is distilled upon creation. However, rainwater no longer remains distilled after the addition of impurities from collecting minerals and contaminants in the environment.

Briefly, rainwater is only distilled if it doesn’t contact and collect any impurities from the environment.

What is Distilled Water?

Distillation creates distilled water.

Distillation is the conversion of water into vapors through heating and then the transformation of these vapors back into the water by cooling.

Distillation is an excellent natural filtration method because it separates water from other liquids and even non-volatile solids (that cannot evaporate into gas even when lit).

Distillation involves two main processes: boiling/heating and condensation.


Every substance has a different boiling point (the temperature at which the substance begins to boil). Most liquids turn to gas after they cross their boiling points.

Boiling a mixture of various substances allows them to turn into gas one after another. We can separate the substances by collecting their vapors into separate containers. This is the main purpose of distillation.

Water contains numerous substances, including contaminants and essential nutrients like minerals and vitamins. Although we need these nutrients, the contaminants in water can harm us, so we try to remove them through boiling.

The boiling point of water is 100℃, so it begins to bubble as soon as it reaches the temperature. The bubbling water evaporates (turns into gas) with continuous boiling.

Water distillation focuses on maintaining the temperature at 100℃ to convert all the water into gas.

The boiling point of various substances in the water differs from it, so they remain in the container when water boils. The water evaporates and leaves the container, while the impurities remain.

Water turns into vapors when its gaseous form suspends in the environment. These water vapors contain no impurities, so we can get the purest form of water if we separate these vapors.


We need to convert these water vapors to liquid form, so we trigger condensation. Condensation is the process in which vapors turn back to liquid.

The water vapors begin to transform back into liquid water by cooling. We can then collect the cooled water. This cooled water is distilled water.

How Pure is Distilled Water?

Distillation effectively separates only the water molecules, leaving out any sediments, particles, and extra nutrients, including minerals, in the container.

The distilled water is extremely pure because it contains nothing but water molecules. You could say distilled water is 100% pure.

Is Rain Water Distilled Water?

Distilled Water

Not many know that similar processes make rainwater and distilled water.

Since the rain-making process is a form of natural distillation, the rain produced is distilled water; but this can change over time.

While distilled water remains pure because it contains nothing but water molecules, rainwater may become impure from environmental contact.

How is Rain Water Made?

Water Cycle is an extensive rain-making process. It involves various steps, but a major part involves natural distillation.

We all know ice melted from glaciers and mountains runs off to the ocean and eventually creates rain. We’re going to ignore this and just focus on the ocean, the sun, and the clouds.

The heat from the sun warms the ocean water, so it evaporates (boiling). The water converts into gas and rises into the air, leaving all minerals and sediments behind.

There’s no container to catch the water vapors, and they can’t transform back into the water with the sun’s heat, so they temporarily suspend in the air. Eventually, when the temperature cools down, these water vapors begin to condense or collect together (condensation).

Since there are countless water vapors in the air, they begin to come closer through condensation. They eventually come together and join each other, forming fluffy clouds.

Clouds are just condensed water vapors and remain suspended until they fall.

The water vapors begin to fall to the ground when air can no longer hold on to their weight and convert back into liquid drops. This creates rainfall.

How Pure is Rain Water?

The ocean water evaporates and leaves behind any extra substances, including minerals, nutrients, salts, and contaminants.

Ocean water vapors are basically distilled because they contain nothing but gaseous water molecules. At this point, the water is as pure as distilled water.

The vapors may remain equally pure when they condense into clouds. But the water droplets may become impure during rainfall because falling from the sky forces them to contact substances in the air.

Yet, simple contact with air won’t do much damage if it contains no pollutants. Clean air allows water droplets to retain some of their distilled purity and only gives them minerals. Polluted air will add various contaminants to the falling rain.

So there’s no fixed purity of rainwater, but it can be 100% if it avoids contact with contaminants.

Rainfall in clean areas might reduce its purity but only to the extent where minerals add to it; for example, the purity may drop to 90%, but this is still purer than most water sources we have.

However, if rainfall happens in an area close to polluting sources like factories billowing smoke, the rain catches smoke, dirt, dust particles, and even bacteria. Its purity level might drop to 40% per se.

In short, the purity of rainwater depends on the area. The dirtier and more polluted an area, the less the purity of rainwater. The cleaner the environment, the purer the rain.

Is Rain Water the Same as Distilled Water?

Let’s get to the bigger question: is rainwater distilled water?

Yes and no. We can say rainwater is distilled water soon after its creation, but it loses its distilled status after contacting contaminants from the air and ground.

So you might get pure distilled rainwater if you collect rain quickly from a clean environment and prevent it from contacting any other contaminants. Still, the rainwater becomes impure if it contacts contaminants.

Rainwater and Distilled Water: A Comparison

Let’s take a closer look at rainwater and distilled water, so it’s easier to understand:

Distilled WaterRainwater
Distillation is a single process that makes distilled waterDistillation is one part of the rain-making process
Distilled water is demineralized; it contains no mineralsRainwater is demineralized at creation but collects minerals from the air and land upon contact
Distilled water contains no environmental substances like contaminants, minerals, nutrients, and even germsRainwater can collect environmental substances, including essential minerals, contaminants like smoke and dust, bacteria, and germs
Distilled water is and remains 100% pure if kept separatelyRainwater begins with 100% purity which gradually reduces
Distilled water remains distilled if stored correctlyRainwater begins as distilled water but eventually loses its distilled status

Which is Healthier: Rainwater or Distilled Water?

There’s a massive debate on the healthier one between rainwater and distilled water since each offers unique benefits.

Many believe distilled water is healthier than rainwater because it is free of impurities. But that’s not the case. Remember, pure does not always mean best.

Distilled water is a safe bet for those whose only other option is unfiltered and possibly impure tap water. But we wouldn’t go as far as to say distilled water is the best for drinking and cooking.

Distilled water might look good at a glance because it contains no impurities but lacks minerals and essential nutrients. So while drinking distilled water might be good because it’s 100% pure, its lack of minerals makes it an unsuitable choice.

You would think distilled water pales compared to rainwater, but the latter isn’t the safest.

The purity of rainwater depends on where it’s coming from and where you collect it, so you can’t declare it as pure as distilled water or impure as tap water.

There are two scenarios at play here; you either collect rainwater when it’s still pure and distilled or get polluted rainwater.

Some countries like Thailand and Brazil use a Rooftop Rainwater Harvesting System that catches rain in a clean drum and purifies it through a system of filters to provide healthy rainwater. Several homeowners also employ the same system.

Rainwater collected in such systems is generally healthier than distilled water because it contains essential nutrients like minerals, and additional filters remove any harmful contaminants.

However, rainwater that crosses through a polluted area, i.e., industrial/factory area, collects harmful bacteria and pollutants, so it’s extremely unhealthy to drink.

Yet, rainwater is slightly better than distilled water since it has beneficial nutrients and components like oxygen and minerals, while distilled water provides no nutritional benefit.

Conclusion | Is Rain Water Distilled?

Distillation is an important part of the rain-making weather cycle, so rainwater is distilled water upon creation. However, while distilled water remains distilled and pure, rainwater loses its 100% pure distilled status after it contacts environmental substances.

Distilled water isn’t the healthiest since it has no nutritional value. Rainwater contains a few contaminants, but you can easily remove them through a simple filter. 

The natural rain-making process produces distilled rainwater but loses its purity after collecting minerals and contaminants upon environmental contact.


This is my blog about the ways and solutions that can help you improve your health by taking more value from drinking water. As improving health means a lot to me, I decided to create the Water On Top project with the purpose to reveal the benefits of water, the finest products to take our daily water to another level, and much more great stuff about water that I believe is on top of our nutrition.

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