How to buy Water Purifier Guide

Is RO water good or bad for health

Before we get to the details, let us be clear about what RO water purifier means. The full form of 'RO' is 'Reverse Osmosis' and 'RO Water' means water which has been purified by an RO water purifier.

RO water purifier is good for health because it is the only water purifier which can remove dissolved salts from water and thus keep you safe against poisoning by deadly heavy metals like Arsenic in water. Also it is the best hard water purifier for homes because it can remove the hardness salts dissolved in water.

Claims that RO water is not good for health is made on three points, one that RO water has no essential minerals in it. Secondly they say that RO water is not good for health because it is too pure like distilled water. The third disadvantage claimed is that RO water is Acidic and thus is not good for health. Below we explain why these allegations against RO water purifiers are not true and why RO is the best water purifier for home drinking water.

Some of the claims that RO water is not good for health are based on a research report published by the WHO (World Health Organisation). People claim that in this WHO report the WHO warns against drinking RO water because it is not good for health. This is not true, please see our dedicated page where we explain the full details of this WHO report

It is true that RO water filter removes all the impurities in water including all bacteria, germs and at the same time removes the dissolved salts in the water. So is there any truth in the claims that RO water is not good for health? does it mean that RO water has no minerals and is acidic and therefore, RO water is not healthy? This is not true!

Essential Minerals in Drinking water

You can never get enough essential minerals from drinking water alone. Minerals required by our body has to come from food we eat, not from the water we drink.

We will prove this to you by putting some figures to this. WHO (World Health Organisation) recommends that drinking water should not contain more than 500 ppm (parts per million) of TDS (Total Dissolved Solids). Water TDS full form is 'Total Dissolved Solids' and TDS meaning in water is the amount of dissolved salts in that particular water measured in Parts Per Million (PPM), PPM is the same as or equal to the dry weight of dissolved solids or salts expressed in MilliGrams (mg) in one liter of water.

So 500 ppm is the same as 500 milli-grams in one Litre of water. A liter of water weighs 1000 grams = 1,000,000 milli-grams (mg). Assume we drink 2 liters of water a day, so the total mineral content that can possibly be got in the worst drinking water is 1000 mg. (2 liters at 500mg per liter of water). Of this normally more than 60% will be the highly soluble sodium salts which are not an essential mineral - you get plenty of Sodium in your table salt. That leaves 400mg of mineral salts other than sodium in 2 liters of water. Assume it is all Calcium, an essential mineral, so the maximum Calcium salts you can get from drinking 2 liters of the worst possible hard water is 400 mg as Calcium bi-Carbonate, which equates to about 160mg as elemental Calcium. Eating one slice of bread or one chapatti will have more calcium - wheat flour is fortified with calcium in most countries.

We are talking about the worst possible drinkable hard water - If you have 200 ppm calcium in your water, it is very hard water which will not taste good. Other than Calcium, the other essential minerals you can get from water are things like iron, magnesium, etc. Iron, even in very small quantities like 1 ppm, makes the water discoloured and taste very bad. All water purifiers try their best to get rid of it. So to put it bluntly, it is impossible to get enough minerals required by our body from our drinking water alone. The essential minerals required by our body has to come from food.

One important point to mention here. The RO water filter is doing its job of purifying drinking water by getting rid of all the salts in the water. This includes all toxic chemicals like Arsenic, Mercury, Heavy metals, Nitrates, etc. which can cause great health damage. In this process of removing the poison chemicals from water, it also removes essential minerals. This loss of essential minerals in water is insignificant when you compare it with the benefits of being sure that your water is free from all poisonous chemicals.

So yes, RO water is too pure, like distilled water, without any minerals, but it is good for health because you are sure you are not getting any poison chemicals in your drinking water. You can get plenty of essential minerals from the food you eat. Also good RO water Purifiers have a remineralising cartridge which can add minerals to the pure RO water at the final stage to remineralise the RO purified water with purified essential minerals like Calcium, magnesium, etc.

Essential Minerals can be added to RO water

RO water is like pure distilled water that is 100% water without any dissolved salts. All RO water purifier manufacturers are aware of this, so some RO water purifiers have a Cartridge called a remineraliser cartridge, filled with purified alkali essential mineral salts of Calcium and Magnesium, through which the pure RO water passes through. Thus the pure RO water dissolves some of the essential minerals from this remineralisation cartridge or an alkalizer to give alkaline RO water. The alkaline RO water is good for health.

Another method of adding mineral salts to purified RO water is to use a portion of the RO reject water to pass through an ultrafiltration cartridge and then blend it with the pure RO water through a blending valve. This is not an ideal method in areas where there are known contamination of poison chemicals like Arsenic, because the purified reject water used to reharden the RO water may contain Arsenic. So water purifier manufacturers who use this method of rehardening makes sure that your raw water does not have Arsenic or other such dissolved poison chemicals. Passing the RO water through the final remineralisation cartridge is the preferred method.

More information about RO water purifiers is available on this page about the Advantages and disadvantages of RO Water Purifier. Below we have a list of all pages in this website and there are many pages giving full details of how RO water purifiers work, the difference between RO and other types of water purifiers, the advantages and disadvantages of RO, etc.

Best way to buy Water Purifiers in India

The best way to buy Water Purifiers in India is to first look at all models of Water Purifiers available online at the leading online Retailers in India. For example on the online webpage of All Water Purifiers available in India on, you will find the full range of Indian Water Purifiers complete with their best discounted price and full specifications. This is great information, and you can decide on which model of water purifier to buy. With the model of water purifier you want to buy finalised, you can go to local shops to try and find the model of water purifier you have chosen and see if you can get at similar price of that at In most cases the price from Amazon will be cheaper, because they buy in bulk from the manufacturers direct and they sell huge volumes because they are the world's largest and most trusted online retailer. If you buy from Amazon, they will arrange to have the water purifier installed in your house, usually free of charge.

Warranty and other facilities offered through Amazon are usually better than what you can get from local agents of water purifiers.

All pages in our website

Below are links to all the pages on this website and we hope you will make full use of all the great information about Indian Water Purifiers provided here.

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