Don't know if this is useful, but I just remembered it.
I've always had trouble getting from breakfast to lunch and from lunch to dinner without feeling very hungry, painfully so. I happened to be seeing an endocrinologist about something else, and mentioned this. He said it was a common thing and advised me to replace some of the carbs with fat and protein, so that I don't crash a couple of hours after a meal.
I tried adding full fat Greek yoghurt to breakfast and an egg to lunch, decreasing the amount of carbs to balance, and now I need to refuel between meals much more rarely. I notice that I have more of a sensation of being full at the end of a meal, too.