Well, if that just doesn't flip conventional medical wisdom on its head, I don't know what will.
So I'm reading "Why We Get Fat" by Gary Taubes, right?
Chapter 9 is titled "Laws of Adiposity" - much of the first section discusses an experiment conducted by George Wade. After removing the ovaries from three sets of female lab rats, this is what he found:
1. The rats who were allowed to eat whatever, whenever gained weight and became obese.
2. The rats who were put on a strict post-surgery diet still gained weight and became obese.
3. The rats who were injected with estrogen and left to whatever eating pattern they chose did not grow obese.
Obviously, this experiment (with further explanation in the book) linked the presence of estrogen to weight loss/gain. Taubes goes on to say "estrogen influences an enzyme called lipoprotein lipase (LPL)". These enzymes pull fat into cells that express a need for it (91). When there is no estrogen, the LPLs go crazy, pulling fat into cells everywhere...then, the animal (in this case, the rat) wants to eat more and more because calories and fat are being snatched by the LPL (92). If the animal can't get the food it wants, the body compensates by slowing down: metabolism, expending energy, etc.
Laboratory rats is one thing, humans are another altogether. I'm paraphrasing Taubes here, but, we've all believed that overeating and underexercising have been the obesity culprit; maybe these lab rats are the key to understanding that obesity is not just a simple matter of eating less and moving more. Perhaps we need to get it through our heads that obesity is its own complex system and network of enzymes and partnerships that have nothing to do with being on the treadmill or eating a salad. He suggests that "when we pay attention to the regulation of our fat tissue, we arrive at an explanation for why we get fat and what to do about it (93)".
I must, of course, keep reading, but this is pretty intriguing stuff, yes?