> Since it supresses appetite, you tend to eat more.
Huh.... appetite is the brain response to going hungry and getting a desire to eat via hormonal / chemical changes within the body.
Suppressing this response means to loose the desire to eat, which is not necessarily the same thing as feeling full, but more like eating becomes a chore, as the satiation (pleasure) response is dulled.
So your comment makes no sense, when your appetite is suppressed you eat less. What happens with sugar is the high glucose levels triggers short term higher energy and to associated stimulant effect from that, and the lack of real hunger satiation response allows the users to gorge too much sugar, whilst at the same time not providing any wholesome nutritional value (lack of variety of micro nutrients - from candy)
There is an old wives tale of giving the children of the family a small amount of candy, before 1950s in time before the main meal of the day. In order to suppress the child's appetite and thus not require as much of the scarce/expensive wholesome food. The largest plate of food is given to the bread winner of the household.
So to me it all depends on who, how and when the sugar is given. A few sweets and hour before a main meal reduces the amount eaten, a soda drink given immediately before or during dinner increases it.
I agree also with the fiber meaning fuller sooner with smaller portions. But that is also true of complex carbohyrates and complex protein (i.e. not whey hydroyslate, but regular beef), actually anything with a higher calorific requirement to metabolize. It costs calories to break down certain foods, water soluble glucose requires less (as do fats) and things like fibre get in the way of the process so its slower and less efficient thus using more energy.