Shootingstar, I LOVE FIber One cereal. I have 1/2 cup every morning, but instead of having it with the puffed cereals, I have it with 1/2 cup Kashi Go Lean cereal - more great fiber AND protein. It's a great combo.
I also put some Fiber One cereal in my fat free yogurt every day. It adds a nice crunch. I put it salads as well in place of croutons. I even munch on it all by its lonesome.
Like Linda, I get over 40 grams a day of fiber. It really is great stuff. Give yourself a couple of weeks. When I first started reducing my calories that's about how long it took til I got used to it. I look back now and don't ever know how I ate as much as I did. Sheesh. Or why.
And by the way, just how low fat are we talking here? We do need SOME fat in our diet. Chicken breast, fish, low fat cheeses, avocado, some nuts - all good and healthy fats - in moderation of course.
I find drinking lots of water also helps to keep me full. You might want to give it a try.
Good luck and happy upcoming 40th birthday.