Since I have diabetes (horrid disease) I watch what I eat all the time.
I also think about what I want most. A cookie or two or a small ice cream later or a bowl of ceral.
I find that when most of my co-workers are eating donuts or cake I get by with a mint or two. It is the small changes you make over time that get the weight off and keep in off.
I don't have a lot of junk food in my house, we snack on veggies or fruit here.
Fast food has never been something we have done. I also try to keep things in the house to eat that don't take long to prepare.
I always have a fruit bowl on my island for a quick snack. Have always had that. Am amazed when I go to friends houses and they have no fruit in the house.
If you go out to eat at any resturant and just look at what people are eating next to you will see why some are heavy and some are not.
Same thing with looking into people's grocery carts. In some people's carts I see a lot of packaged foods, pizza's, frozen processed food, lots of snacks, fried foods, white breads Donuts, cookies, ice cream things like that. We Americans love our food but it does not love us back it kills us when we eat the wrong things over the years.
Best of luck to you. Even a small impovement in your eating is a great thing.