There are a couple of theories about how this one got started and the most commonly referenced one talks about lab studies where SUBJECTS who ate late at night gained twice as much weight at the control group despite the fact that they were given the same amount of calories.
One thing that this study will normally omit is the fact that the "subjects" in question were rats, not people, and it kind of makes me wonder why they would conceal this information? I can only guess that they were trying to get published and get paid. Whatever, it isn't understood why this happens with rats but it doesn't happen with people, who as you might have noticed, are slightly physiologically different from the average rat.
I have always had positions that had strange schedules. For this reason or that, I didn't spend much of my life with a 9-5 type job. Therefore, my eating schedules were all over the place. Sometimes this incorporated eating late at night and to be fair, that is pretty common for me now as well because I tend to enjoy being awake late. It's just how I roll.
There have been a number of studies that were done on groups of people that show that they maintain better weight if they eat their major meal in the afternoon... but then other studies that show that the same is true for those that eat a big breakfast and smaller meals.
For some reason everyone really wants to get on the case of people that will have a big dinner, or even worse if you have a big meal say, after 8pm.
Here's the things they don't tell you. For whatever reason, the studies found "People who tended to sleep and wake later ate the bulk of their calories after 8 pm, more calories overall, and fewer servings of fruits and vegetables."
These observed people always lost less weight or simply had less desirable results than other groups but look in the middle of the sentence where it says "more calories overall" and you have your answer.
While there is some science behind lying down and going to sleep after a big feed instead of going for a walk or whatever, I don't think we need to get the guys in the lab coats involved to understand why this would result in less burning of calories.
Your fitness and weight goals are based on the amount of fuel you put into your body minus the amount of calories that you burn... PERIOD
Whether you space your meals around the day in a "normal" pattern, or eat them all at once doesn't matter as much as you think. Of course there is a real danger in eating AGAIN late at night but if that is when you normally eat, and it isn't your second dinner, then dig in pal! It doesn't make any noticeable difference and if you look at honest studies that use humans as their subjects instead of lab rats, (who are nocturnal creatures anyway) the studies will come to the same conclusion.