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Reverse Osmosis Vs Distilled Water: Which is Better Choice?

Fact checked by Stephen Conklin

Reverse Osmosis VS Distilled Water

Are you looking for info on reverse osmosis vs distilled water? In supermarket chillers packed with lines of bottled water, you’ve probably seen the words “distilled” and “reverse osmosis” on labels a few times. Perhaps you never bothered to figure out what these mean.

Getting up for a glass of water is such an essential activity, you don’t even have to think about it. It’s just water – why be bothered to know the difference between distilled or reverse osmosis?

As it turns out, there’s more to these two than just making your water taste differently.

Table of Contents

Why Do We Need to Purify Water?

Water is everywhere, making up most of the Earth, but drinkable water is tough to find. Throughout history, humans have invented ways to make water safe to drink. From filtering river water through the sand to boiling it all day or adding chemicals – we’ve tried it all.

These primitive methods have since been improved, of course. Today, there are numerous ways to purify water. To name a few, you have chlorination, distillation, boiling, filtration, and reverse osmosis. Clean drinking water is purified by utilizing two or more of these methods.

What Is Distilled Water?


When a water bottle is labeled as “distilled water,” it means that its water went through the process of distillation. Distillation has other variations, but essentially its primary purpose is to remove sediments from water.

The water is boiled, and the resulting steam is then captured. As it condenses back into liquid form, it drips onto a separate container, and the resulting liquid is then called the distillate.

The process of distillation is effective in removing salts and minerals from the water. Removing these solids helps soften the water, even though some of these minerals turn out to be good for you. Since distillation can’t tell the difference between good and bad solids, it just removes all of them.

Magnesium and calcium minerals that harden water contribute to the taste that you expect from water. Since distilled water nearly has little to no minerals, the water ends up tasting flat and bland. If you’ve ever had distilled water, and you’re one of those who dislike the taste, now you know why. It needs a bit of salt.

Other than tasting like nothing, distillation is also incapable of removing chemicals with a similar boiling point to water. Because of this, an additional purification method is usually applied to the distilled water, whether it be reverse osmosis or filtration through a layer of activated carbon.

While helpful, these supplementary purification methods add to the already lengthy process of distillation. Distillation alone takes hours to complete, so don’t be tempted to set up your own distillation station at home. It’s not the most convenient purification process for places that need a lot of drinking water right away.

Is Drinking Distilled Water Safe?

Now, distilled water is not all that bad. If you had to choose between unfiltered water and distilled water, you’re better off with the latter.

However, because distilled water lacks salts and minerals, it will try to balance this out by pulling in minerals from any material it comes in contact with. If you store distilled water in a plastic pitcher for too long, you could end up drinking bits of plastic.

Although the lack of minerals in distilled water makes it unpopular among water drinkers, their absence helps other activities. Steam irons, aquariums, car cooling systems, and certain laboratory experiments all require distilled water to function correctly.

What is Reverse Osmosis?


To know about reverse osmosis, you first have to know about osmosis. Osmosis is a process that involves solvents, solutes, a semipermeable membrane, and a solution.

Picture out two solutions, each with their solvents (liquid) and solutes (dissolved particles). The first solution has lesser solutes, while the second solution has more solutes, and they are both separated by a semipermeable membrane.

Osmosis occurs when the solvent of the first solution moves through a semipermeable membrane and goes to the second solution, where there are more solutes. The goal of this natural process is to equalize the concentrations of each side. The liquids will continue to go where it’s needed until the solution on each side of the membrane is the same.

So now that we’ve got that covered, let’s reverse the entire procedure. Reverse osmosis, as the name states, reverses the natural process of osmosis. It starts with a solution with many solutes – or in the case of water, a lot of contaminants.

Reverse osmosis takes contaminated water and forces it through a semipermeable membrane at high pressure. As the water passes through, it leaves behind minerals, salts, and other microbes. Some reverse osmosis devices even have a sedimentary pre-filter installed to remove larger solids, as well as an activated carbon post-filter that absorbs chemical contaminants – making the process one of the most effective ways to purify water.

What Are the Health Benefits of Reverse Osmosis?

In effect to being a highly effective water purifying process, reverse osmosis reduces contaminants deemed deadly or toxic. Nitrate, perchlorate, arsenic, and hexavalent chromium are just a few examples of the stuff it leaves out – assuring you that your next water break won’t be your last.

Other than this, reverse osmosis systems also are very effective in removing bacteria. A few contenders that frequent tap water – Campylobacter, Salmonella, and the ever-so-popular E. coli – all get removed by reverse osmosis.

Additionally, reverse osmosis is also known to remove viruses. You heard that right, viruses. Enteric, Hepatitis A, Norovirus, and Rotavirus are no match to the multi-filtered and high-pressured forces of reverse osmosis systems.

How Long Does a Reverse Osmosis System Last?

This answer will depend on how well you maintain your reverse osmosis filter. If you put your best foot forward and replace the parts as needed, this system will last you forever.

It’s recommended that the sedimentary pre-filter be changed every six months, as does the activated carbon post-filter. If you suspect that your water source contains more contaminants, you have to change these filters more often. Watch out for any changes in your water’s taste and smell to avoid damaging your reverse osmosis filter.

The reverse osmosis membrane itself can last for up to two years before it needs a replacement. This will still depend on the quality of your water, and how you maintain your system. To keep it in tip-top shape for longer, make sure to shut it off when you’re not using it and drain the water regularly so that it doesn’t clog up.

Reverse Osmosis Water? Distilled Water? Or Both?

Distillation removes all contaminants and all minerals. Reverse osmosis water removes impurities, chemicals, bacteria, and viruses while minerals remain.

If you’re looking for a long-term water purifying system that’s sure to keep you and your family safe from all types of sicknesses, then reverse osmosis is your best bet. If you’re looking to quench your thirst and chanced upon an unopened bottle of distilled water chilling in the fridge, that’s fine too. You can refer to many other water filters such as whole house water filters, NSF-certified water filters, or MWF water filters.

The main point of purifying your water is so you can stay alive. While one may taste better than the other, the other is still useful in many respects. Nevertheless, you know reverse osmosis vs distilled water differences and highlights from now on.

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