Thanks for that.
Annoyingly our water smells a bit chloriney, and furs up the kettle something rotten.
We filter it with a Brita, but after two weeks ago the kettle starts furring again.
In addition to the increased sodium ion concentration, the ion-exchange resins inside softeners can support bacterial growths...not really something you'd want to drink without boiling...and the water can also get an unpleasant "flat" or "stale" taste.
I think that statistics show that there is a higher rate of certain illnesses in soft water areas. So, the softener industry covers its back by leaving the drinking water supply unsoftened. That's what I think, but not to be taken as authoritative.
I have got a three way kitchen tap. Softened hot, untreated cold off the main and a third tap that is connected to a cylinder filter fitted under the sink. I live in a very very hard water area and always fill the kettle from the third tap. Kettle never furs up and the water doesn't taste of chlorine. Like this Amazon.co.uk User Recommendation