Allow me to try to answer this one (even though the question wasn't directed to me). If your diet is high in carbs, your body is producing insulin to take the sugar (carbs are sugar) out of your bloodstream. Unless you happen to be running the Boston marathon at the time, those "carbs" are usually stored as fat cells. Then you are hungry again and the whole cycle starts over again.
By eating foods high in fat and protein and avoiding sugars (carbs), your sugar level stays constant and the protein and fat causes what is called "satiety" and you no longer feel hungry. (Your body will produce its own sugars if it needs it - you don't need to eat them at all.)
This is why when you eat a cheese omelette for breakfast with a slice or two of bacon, you feel full and have no problem even skipping lunch. However, if you have a big bowl of cereal with milk and orange juice with toast, you are hungry two hours later.
This happened to me for years. And I never realized what was going on. For example, when I had breakfast, I'd have a bowl of Wheaties with unbuttered toast despite the fact that what I really wanted was the bacon & eggs. I used to praise myself for my "self-control" to eat right and eat healthy. At a restuarant for dinner, I'd pass on the steak (which was what I really wanted) and get a bowl of pasta or something, again, thinking that I was making a healthier choice. In fact, I used to fill myself up with bread at restaurants so I wouldn't eat so much of the main course. I actually thought this was a good thing.
Since I went "low-carb" on April 1, I have lost 44 pounds and I do my weekly weighing tomorrow so I'll likely add 2-3 pounds to that total then. I should emphasize that I am not on the "Atkins" Diet and never was. Thus I did this without the "induction phase" that Atkins promotes which pretty much eliminates carbs totally. (But I do walk 6-8 miles a day so that probably made up for it.) I figure I am between 50-100 carbs a day on average since April 1 - still a far cry from the days where I consistently consumed 300+ carbs a day! It makes a big difference.
So to sum it all up, it's probably not really your slow metabolism that is at issue here. It's probably the kind of foods you are putting into your body.