As we know that water is most essential thing on earth to sustain life. On earth , no any living being can survive without water. Hence, water is the most required thing on earth. In India, peoples were drinking normal water, getting from underground source and floating stream. That time, environment was pure and healthy. Due to modernisation, pollution has created life threatening cases for living being. Because due to increase in industrialisation and facility, an evil is called as pollution has came in to existence. Pollution has disturbed the all biological factors of living being.
Generally for human being, consuming clean natural water is big problem. With that many branded companies are stood for marketing there water system product. And peoples are ready to purchase these product from market. Demand of various types of RO system in the market is more. Peoples are continuously adopting such water purification system and use to drink such purified water. Due to lack of knowledge for health, peoples don't know, how such purified water is harmful to human health. For human being, normal water received from nature is much better for health. Question is here, how the purified water is harmful for health. Some essential minerals are most required for human body which generally obtained from ground water. So these essential minerals are removed by RO treatment and cation and anion exchangers. Even these minerals are not obtained in regular diet. Due to lack of essential minerals, various diseases are caused.
Another thing is that, by water purification system, basic normal flora means essential micro organisms are removed by RO treatment, UV treatment, Ozonization, Chlorination etc. In purified water, essential micro organisms are found approximately absent. So the regular drinkers of these types of purified water having weak immunity. And they fail ill. Even a normal micro organisms can make to suffer a mild infectious disease. I had read in immunology in my 3rd year of college that if a body is exposed to any antigen then a body will develop immunity by generating antibodies in body against those antigen. But if a living body is not exposed to antigen of micro organism and suddenly attacked by micro organism. Then the living body may adversely fall ill and suffer from heavy infection.
Boiled water is much better than purified water. Because presence of living micro organism will be almost nil by boiling water at 100 degree celcius. But antigen of killed micro organism remain present in boiled water. So the chances to cause disease become zero and immunity of body increases. The body don't loss his immune response ability.
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