One of my DCs is a carb monster - will single out processed carbs like a heat seeking missile but any carbs will do.
I wasn't as vigilant as maybe I should have been as the others just never did and it was only once I watched one dinner with my eyes really open that I realised.
He gets, or seems to, much more feedback from eating carb heavy fruits (always a Banana vs citrus), breads and things that aren't low GI, he is much more affected by blood sugar highs and obviously the blood sugar lows, he needed to eat more frequently otherwise he just smacked into a Bsug dip and felt rubbish. And behaved as such.
I think that his high led into a habit as we often had the same asking for food when I'd tightened up his diet for about 2 months.
I had to approach it like you do when a child is stuck on the refind sugar roundabout. Although our meals had good amounts of proteins (animal and vegetable) and I made sure we started eating protein, then veg, then any starches last so he didn't fill up on them and then start hunting for more food at bedtime; and I changed his snacks to limit his carb intake to fruit and veg (berries, grapes, carrots etc) then the rest was protein. I found with him if I started the day with toast he would then be primed to seek out bread,cakes etc so he gets eggs or low GI type breakfasts.
Now he's older he is actually very good at being sensible and if he's been at a friend's he'll let me know he had a lot of food x and we'll make sure dinner has something guaranteed to carry him over into the morning.
Sorry that was an essay - I think my point is that it's a good time to do as you are and re-assess, he may well feel hungry and a bit yuck if he is like my DC and swapping out some of the pancake/scone etc type rib sticker snacks with higher protein and some of the higher sugar fruits for others may help even it out, he'll be less hungry but have really good building blocks for growing. I wonder if you'll get him up one day next week and he'll have shot up overnight?!