Interesting item in the latest New Scientist magazine. Some scientists suggested that a major contribution to the obesity epidemic is the use of bedroom heating. Apparently, if you sleep in a cold bedroom, you expend a lot of calories in keeping warm. If you heat the bedroom to your comfort zone, calory expenditure goes down. The last few decades, coinciding with the increase in obesity, has seen more and more homes fully heated. Coincidence or not? I don't know.