I've been controling my intake this year yes. I gained the freshman 15 last year and have been trying to think about what I eat so I don't gain another 15.
I look on the lable and keep an eye out for the flowing:
Transfat - Transfat is directed right to your fat stores and is harder to loose.
Saturated Fat - While not "bad", it's best to limit this sort of thing.
Monosaturated fat - The good fat, this keeps your systems (blood and lymphatic system IIRC) lubed up and working in proper proportion.
Calories - While, I don't count them - I try to stay away from high calorie, non filling foods. For example - twinkies, dingdongs, dounuts, etc are all high in calories but low in actual mass. Grapes, citrus fruits, etc are all very low in calories due to their water content - which makes up most of their mass.
As far as actual content - I try to stay away from processed bread and anything with high fruitos corn syrup listed in the first 5 ingredients. Corn syrup is just not healthy and if you imbibe too much in one day, your body will try and convert it to fat. Processed breads do not have the fibrils inside of them, and causes your body to retain a lot of the bread and convert it likewise to fat.
James