I believe the idea from above poster is not that you should stop heating and "live like a caveman", but that many people would make great savings by wearing a wool sweater on top of their t-shirt and turning the temp down a couple degrees. As a case in point, I never spent a winter with 22°c indoors, usually it's around 18-19°c.

That being said, as someone else said, controlling humidity is also a concern for the long-term viability of buildings.