I wanted to clarify one thing about the winter metabolism that I wrote about. I am not saying that winter (or lack of Vitamin D) causes obesity. Instead, I am saying that the modern diet and lack of sunlight can put a person in continual winter mode, such that obesity is the result over the long run.
In normal situations, perhaps the winter season leads a person to gain a few pounds and then they lose that weight in the spring/summer. Nowadays, the modern diet and indoor living trap a person in this winter cycle. The result is slow weight gain over the years and other associated health problems.
