There is a draft report from the World Health Organization that says: "Salts are leached from the body under the influence of drinking water with a low TDS. Because adverse effects such as altered water-salt balance were observed not only in completely desalinated water but also in water with TDS between 50 and 75 mg/l, the team that prepared the 1980 WHO report recommended that the minimum TDS in drinking water should be 100 mg/l.
"Demineralised water that has not been remineralized , or low-mineral content water – in the light of the absence or substantial lack of essential
minerals in it – is not considered ideal drinking water, and therefore, its regular consumption may not be providing adequate levels of some beneficial nutrients."
Click to read more of this WHO Report
. We note that this is a draft - but we're unclear why you post a paper on the internet if it's not to be shared.