True. But what happens in between is what matters. It is called metabolism
>> Yes, disrupting your sleep patterns may affect the "calories out" department slightly, but that is not what is making you fat. It is food that is making you fat.
It is both. Sleep restriction or sleep deprivation have been shown to limit normal insulin activity. Instead of pulling glucose into cells where it can be used, the glucose remains in circulation. Some is converted to fat. The higher blood glucose levels is also known as diabetes. So when controlling for other factors, weight gain and diabetes (type II) is seen with sleep deprivation.
Sleep deprivation also changes hormone levels relating to appetite and satiety (feeling full). Look up grehlin and leptin. This fits with the "calories in" part but is driven by biological factors rather than personal failing and character flaws.
Less sleep ==>more hungry. Less sleep==> more fat storage.
Yes, people to should eat less and exercise more. I give this advice to patients that I treat. They should also sleep in more natural patterns. I give this advice as well. The motivation, concentration and executive function required to manage new routines are brain functions that also fall victim to sleep deprivation. Put another way, sleep deprived people are less effective than well rested people. So the capacity to work out a new diet (cooking, shopping and time management) is a greater challenge. Ditto exercise. It is still doable and therefore you will read slashdot contributions from those who have been successful. They are probably more to the right side of the bell curve and high functioning even when sleep deprived. But the plural of anecdotes is not data and the population at large will not have the same level of success without health care guidance.
>>Those who cannot understand the box are doomed to think inside it.