As reported by The Birmingham Post (UK), insufficient sleep can make you fat:
The Warwick Medical School study, led by Professor Francesco Cappuccio, found that adults who slept for less than seven hours and children who regularly got less than ten hours’ rest faced an increased risk of obesity . . .
He said: “The epidemic of obesity is paralleled by a silent epidemic of reduced sleep duration, with short sleep duration linked to increased risk of obesity both in adults and in children as young as five years old.
Until I discovered the magic of incorporating whole grains into my diet, I often struggled with my weight. About five years ago, I lost more than 30 lbs and I’ve been able to keep it off. I’ve noticed, though, that sleep deprivation makes me tend to reach for more calories than I need. It’s as if my body is compensating for lost sleep by trying to take in unnecessary calories. It’s not an obvious connection, but I noticed it (as have others with whom I’ve discussed weight loss). [Yet another example of non-intuitive feedback loops. See here and grumpypilgrim’s comment here].
I’m posting this link for the benefit of those who struggle in the same way with I do. It might, indeed, be important to consider proper sleep (along with exercise and eating strategies) in order to maintain appropriate weight.
And obesity shares a high correlation with sleep disorders such as sleep apnea. At this point we don't know whether obesity causes the the condition, which results in numerous awakenings in the middle of the night, or whether the sleep loss caused by sleep apnea contributes to weight gain.
The over-caffienation of Americans comes to mind, too. A reasonable amount of caffiene has health benefits, but excessive consumption makes sleep less restful (and more difficult to attain in the first place). This could contribute to weight gain in the same way that other forms of sleep deprivation do, in addition to the increased stress and addiction that comes from the drug.
I noticed when I don't get enough sleep, my mind and body both feel dead. I don't have to understand the interaction between the brain and metabolism. No sleep = slow metabolic rate. The brain rules, no sleep, no life. You eat during hibernation, you store fat.