RO water ‘total dissolved solids’ below 25: What it really means for your health

Total dissolved solids (TDS) below 25 mg/L is often considered safe to drink, but this does not necessarily mean it is free from contaminants. Dr Udit Gupta, a nephrology consultant, explains that TDS measures dissolved substances like minerals and salts but does not directly indicate safety. A low TDS reading does not mean the water lacks essential minerals like calcium and magnesium, as most of these minerals are obtained through food.

While it may taste less flavorful, very low TDS water is not automatically harmful and should not be the sole factor in determining water safety. It is crucial to consider the source water quality, treatment methods, and regular microbiological and chemical testing when assessing safety. People with medical conditions or those on strict fluid/electrolyte requirements should consult a doctor before making significant changes to their water source.

Ultimately, TDS should be one of several factors, not the only one, in ensuring safe drinking water.