FIT WebQoof: Is Drinking RO Water Harmful?

Drinking mineral deficient RO water may result in long-term health problems.

(Photo: FIT/Erum Gour)

CLAIM: A PDF file is doing the rounds on social media that claims the WHO has issued a warning against RO (reverse osmosis) water.

Various versions of this claim have been circulating since 2017 across social media.

We found a Youth Ki Awaaz article on it in 2015 as well, but it has since been deleted.

True or False?

There are several claims and layers to this message, but first let’s start with the basics. What is RO?

RO is a technology and not a product.

Suresh Rohila, senior director at Centre for Science and Environment explains, “RO is a water filtration technology and it can be combined with other methods like RO+UV filtration or RO+UV+UF systems.”

The bottled water we get outside is mineral water, not RO water.       

Suresh Rohila.

Is RO Harmful?

Rohila says that first it is important to clarify what the RO process does, “ Yes, RO does remove everything and the end product is pure liquid water free of all chemicals, minerals, pollutants and TDS (Total Dissolved Solids).”

According to Safe Drinking Water Foundation, “TDS represents the total concentration of dissolved substances in water. TDS is made up of inorganic salts, as well as a small amount of organic matter. Common inorganic salts that can be found in water include calcium, magnesium, potassium and sodium and carbonates, nitrates, bicarbonates, chlorides and sulfates.”

Rohila adds that “Removing everything from the water, including minerals essential to our body functioning can affect us in the long-term, health-wise.”

Dr Suranjit Chatterjee, senior consultant of internal medicine at Indraprastha Apollo Hospitals told us that, “Calcium and magnesium are absolutely essential for the functioning of our vital organs and our cells.”

Calcium is the most important for bone health and mineral water is one of the sources, so if there is no calcium in the water, over time your bones will become weak. Calcium is also important for cardiac functioning, so if there is a lack, this can be harmful.

Dr Suranjit Chatterjee.

He added that magnessium is a cell membrane stabiliser and a lack of it will indeed cause cramps as the claim said.

One of the claims in the message

To another health claim, Rohila added that the mineral deficient RO water “absolutely dilutes our electrolytes.”

Read About RO and Actively Participate in Your Own Healthcare

“It is important for people to scrunitise RO more , there is no blanket yes or no on using the product”, says Rohila.

But he added that the manufacturers of RO systems need to improve transparency meaning the water composition post purification should be written clearly on the RO system itself.

The industry should do more. People should demand that their RO companies disclose what all they are clearing from the water. Like aerated drinks companies issue a warning saying that children should avoid drinking it, similarly RO companies should disclose if the water is good for vulnerable people like children and old people.     

Suresh Rohila

The Importance of TDS

Coming back to TDS, a lot of new water purification models with RO systems have a TDS controller from where you can control the level of TDS purified according to your health needs.

For example, a person with low calcium can set a different TDS level to ensure less calcium is filtered away from the water so that they can consume clean but calcium-rich water.

It is important to ask your doctor and consult with them about your own specific health needs and adjust your TDS accordingly.  

Suresh Rohila

Bhitush Luthra, water scientist and director at the Centre for Science and Environment, added, "I partially agree with the claims of the message, but the thing to note here is at what TDS you set your RO at."

Don’t Panic But Exercise Caution

But there is no need for alarm, the water you are getting from your RO is not poisonous, but it might rob you of essential minerals in water. There is a solution, doctors can prescribe medicines to restore your calcium and mineral levels.

Rohila concludes by saying, “Ideally, RO water should be taken with caution, the fine print should be known to everyone as different people have different issues and response rates, but it is important that the RO companies warn vulnerable people.”

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