Mummer
12c is far too cold and risky! Also it means your boiler has to work so much harder to heat the house when it is put on, using power less efficiently. 15-16c is optimum with Woolies etc. And easier to boost if it gets really cold. Becareful as hypothermia creeps up and symptoms are very hard to spot, quite hazardous to be below safe temperature specially as we get older and less active.
Totally agree about 12 degrees being too low, especially for elderly people. I understand that living areas should be heated to 18 degrees although bedrooms can be lower, any lower and your health could be affected.
Personally, my house would be damp and mouldy if not well heated, I suffering from damp problems for five years until I replaced the old, ineffective boiler - mould on walls, damp mattress, nasty smell, condensation etc.
I guess lifestyle can make a difference, a younger person who is always rushing around looking after a young family could cope with lower temperatures than someone like me, older, restricted mobility and recently retired so in the house during the day.
I have increased my donations to a local food bank as I know more families are being forced to use them but I still feel guilty that I can afford to pay the increases in my household bills as I can make savings in other areas if I have to.