I believe it.

I know that for me, when I'm tired, I'm constantly fighting an internal battle to 'wake myself up' or 'make myself feel better' or 'get a little more energy' from food. And it's always high carb/high sugar items that come to mind. If I wasn't watching my intake so closely, that would easily translate into a lot more calories consumed without even thinking about it. And I'm not even *that* sleep deprived as a general rule!