I am willing to accept everything these studies show, except this part:
“Van Cauter has made a radical discovery: that lack of sleep may be contributing to the epidemic of obesity in this country through the work of a hormone called leptin that tells your brain when you’re full.”
If you sleep less than 8 hours per night then naturally you’re going to need more food for energy.
I think you miss the point. If you are doing manual labor, then eating more food during that time is critical and doesn’t lead to obesity, but if you like to sit up reading all night and eat more to stay awake, then it does lead to obesity in most people.