Even experienced travellers hold on to fake information about health risks. The water of foreign countries is often assumed to be dangerously contaminated, hence the huge sales of drinking water in plastic bottles. Sadly, the bottled water industry has been so successful in its marketing that locals, too, often think that tap water should be avoided.
To avoid all doubt (and minimise the amount of plastic you use), why not travel with at least a one-litre reusable bottle and some water sterilisation tablets? Then, if boiled water or hot drinks aren’t available, you’ll still be able to keep hydrated.