Reverse Osmosis Disadvantages
Is There Any Academic Proof? 

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By Ali

(Gorgan, Iran)


Hi Nancy, about reverse osmosis disadvantages, is there any academic research to prove the disadvantages of this method? Does the EPA have the same idea?


Ali, I am not aware of any academic research that highlights the negative aspects of reverse osmosis. We know for a fact that the R.O. method does remove many contaminants from water, so that is a good thing.

You can find detailed information about levels of contaminant removal on any site that sells reverse osmosis filters online.

The EPA does not endorse specific types of water filtration or water purification systems. However, they have set up certification standards  as noted on their site:

“While EPA does not endorse specific units (water filtration or purification systems), the Agency does set and enforce national standards for the tap water provided by public water systems.”

You can read more here about water quality and water filtration standards on the EPA site:  Water Health Series: Filtration Facts

I don’t think there is any question that drinking reverse osmosis water is going to be healthier than drinking dirty water or contaminated water.

However, from a health standpoint, I highly recommend drinking water from a home water filtration system (using NSF 42 and 53 certified multi-stage carbon filtration) rather than a reverse osmosis system for a number of reasons, some of which are supported by third-party research. 

Reverse Osmosis Disadvantages

Even though reverse osmosis does remove many contaminants, it does NOT remove some solvents, pesticides, chlorine and other volatile organic chemicals (VOCs) because the molecules of these substances are small enough to slip through the R.O. membranes.  

See “Further Reading” below to find out more about the health concerns related to these types of water contaminants.  

An NSF certified multi-stage water filter system that includes Activated Carbon media (such as the Aquasana AQ-5300 under sink system) will remove most of these substances. NOTE: Click on the “Performance” tab on the Aquasana link to see how this type of filtration works.

In addition, it is very difficult to tell if a R.O. membrane is damaged and is thus not removing the contaminants. 

Minerals in Water Are Removed with R.O. 

Natural occurring minerals in water, such as calcium, magnesium and potassium, are removed during water purification processes (reverse osmosis and distillation) because the mineral molecules are too large to pass through the membrane.

As far as I am concerned, de-mineralization is one of the main disadvantages of reverse osmosis water.

Bob McCauley, CNC, author of The Miraculous Properties of Ionized Water, explains what happens when we drink de-mineralized, or purified, water:

“Since it has been transformed into an unadulterated chemical substance (H2O), purified water naturally seeks to balance or mollify its extremely pure, acid condition with an alkaline buffer.

"Removing minerals from water makes it hungry for anything that is not like itself. All things in nature strive to balance themselves. 

“What is immediately available to purified water when it is consumed are the alkaline minerals and other alkaline material from the body.

"Thus they are absorbed by the pure water and carried away with it as it leaves the body. It is the extreme characteristics of purified water that encourages this leaching of minerals from the body. 

“Purified water also leaches plastic from the bottles it is contained in, which makes drinking purified water worse when consumed from a plastic container.”

Is it scientifically proven that de-mineralized water leaches alkaline minerals from the body?

I have heard of studies that have been done in Japan to confirm this, but I do not have access to them.  But it makes sense to me.

And I have come across studies that show that drinking mineral water does provide health benefits, such as a 2012 study done at Montana State University.  

In addition, after drinking reverse osmosis for several years, I experienced symptoms of mineral loss in my body. Since changing my drinking water from reverse osmosis to ionized alkaline water in 2007, I was able to reverse the loss of bone density. 

Reverse Osmosis Water Is Acidic

The healthiest waters found in nature—water from glacial melt, artesian wells, or pure springs—are mineral rich and have an alkaline pH (7.5 or higher).

When the alkaline minerals are removed from the water in reverse osmosis, the water becomes acidic.  

According to Herman Aihara in his book Acid and Alkaline:

“If the condition of our extracellular fluids, especially the blood, becomes acidic, our physical condition will first manifest tiredness, proneness to catching colds, etc. When these fluids become more acidic, our condition then manifests pains and suffering such as headaches, chest pains, stomach aches, etc.”

Many health professionals advocate the importance of the acid-alkaline balance in the body.

Acidosis in the body—primarily from toxic accumulation, environmental pollutants, dehydration, poor eating habits, and high levels of stress—is one of the primary causes of disease conditions in the body. For more information on this topic, see the list of recommended resources below.

In addition, it has been scientifically proven that when the fluids in our body become more acidic, the body produces more free radicals, the unstable molecules that are known to cause damage to cells and tissues.

I know of some well-known health professionals who promote purified water, and they have a right to their opinion. There are many more well-known professionals who do not advocate it. Just to name a few:

One of the foremost water experts, Dr. Batmanghelidj, writes in his book Your Body’s Many Cries for Water:

“The longer one drinks purified water, the more likely the development of mineral deficiencies and an acid state. Disease and early death is more likely to be seen with the long term drinking of purified water (distilled and reverse osmosis)."

Dr. Batmanghelidj's writings are based on more than twenty years of clinical and scientific research into the role of water in the body. 

Zoltan P. Rona, MD, MSc, writes, “The longer one drinks distilled water, the more likely the development of mineral deficiencies and an acid state. . . .

"I have done well over 3,000 mineral evaluations using a combination of blood, urine and hair tests in my practice. Almost without exception, people who consume distilled water exclusively, eventually develop mineral deficiencies.”

NOTE:  Some R.O. systems now offer an add-on remineralization cartridge to their systems. Adding these minerals will help offset the negative effects of de-mineralized the water. However, I am not convinced it is the same as retaining the minerals in the water naturally.

Reverse Osmosis Changes Water Structure

Water has a specific structure, which varies with environmental conditions. The study of water structure is now an established field of science.  

The size and shape of the clusters of molecules in water after it is purified by reverse osmosis or distillation is significantly different than regular water. 

According to McCauley, “The structure of a purified water molecule cluster is five-sided or pentagonal, and the angle at which the molecules come together, called the bond angle is extremely large (104 degrees), thus forming a water molecule cluster that is also quite large.

“The larger the bond angle of the water molecule cluster, the less hydrating the water is. These large water molecule clusters do not have the ability to penetrate body tissue or its cells efficiently. This is why purified water does not hydrate the body well and can even leave it dehydrated.”

Japanese researcher, Dr. Masaru Emoto, showed how purified water destroys the natural crystalline structure of water in his numerous studies. His studies used distilled water but the same is true for reverse osmosis water.

When the innate structure of water is destroyed, it makes the water essentially useless to the body. Thus, the Japanese scientists refer to purified water as “dead water.”

Summary: Reverse Osmosis Disadvantages 

Drinking reverse osmosis water is certainly healthier than drinking contaminated water.

Even though the topic of water filtration vs water purification is somewhat controversial, my personal experience, research, and common sense has convinced me to recommend filtered drinking water over reverse osmosis water.

And to take filtered water a step further, water ionizer systems add even more benefits, including super hydration, alkalinity, body cleansing, and anti-oxidant potency.

Nancy Hearn, CNC

Alkaline Water Ionizer Reviews and Recommendations


Bob McCauley, CNC; The Miraculous Properties of Ionized Water; 2008.

Herman Aihara; Acid and Alkaline; 1986.

F. Batmanghelid, M.D.; Your Body’s Many Cries for Water; 2008.

Masaru Emoto; The Hidden Messages in Water; 2005.

Additional Resources:

Dr. Felicia Drury Kliment; The Acid Alkaline Balance Diet: An Innovative Program for Ridding Your Body of Acidic Wastes; 2002.

Dr. Mu Shik Jhon; The Water Puzzle and the Hexagonal Key: Scientific Evidence of Hexagonal Water and Its Positive Influence on Health; 2004.

Sang Whang; Reverse Aging; 2006.

Return from Reverse Osmosis Disadvantages to Filtered Drinking Water

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