Blinding, weight loss is pretty low on the list of benefits of exercise. You can easily drop the pounds without getting active.
It's important to go with what's backed by science. In the simplest sense sugar is the issue. Problem is eating excessive carbs will turn to sugar. There's a reason a diabetic on a low carb diet will have their blood sugar go down.
Play the High fructose corn syrup game. Look how many foods contain it. It's disgusting.
IMO anyone who is trying to lose weight should be playing the HFCS game, I alone lost 25lbs JUST from cutting out HFCS, I did not do anything else, and I didn't exercise any more than normal. I just started eating better, making sure I don't eat HFCS in anything and eating more fruits and veggies. I think it really works. I have also kept the weight off for like 4-5 years. I am really sedentary, but I still lost weight. I am also battling various foot problems and a previous ankle injury which still nags sometimes which is why I am sedentary, I won't go into grave details, but it really sucks when your feet hurt and you want to move around instead of being confined to a chair. I am at a time right now where my feet are feeling pretty good now, lets just hope it stays that way so I can walk a lot this summer.
Also unless you are on a really strict diet a little bit of ice cream is ok, if you are eating it at home measure out 1/2 cup which is a serving, and only have it like once a week. A lot of ice cream has HFCS but you can get kinds without it. I eat a little bit of candy every day, but just 1 bite since I have a terrible sweet tooth. Most candy actually doesn't have HFCS, and yes I shouldn't be eating it and I know that, but I have to have that little bit of sweet in my life. If you are at the ice cream shop with friends or you are forced to be there just get a baby cone, its amazing how large a baby cone actually is, it will be more than enough. Sometimes you have to ask as a lot of places don't have baby size on the menu but they do have it if you ask. It won't hurt if you only get it a couple times a summer.