Overweight hamster

Question
My hamster is seriously in my opinion bigger than what it should be. How big are they supposed to get? My hamster is a syrian short haired. It began getting bigger this one week where my family overfed her and she got bigger from then on. Now she just runs in her wheel for a little bit and then gets off, stands on her feet and goes to the bars and does it all over again. I feel bad for her and i want to help her lose weight. Please tell me what i can do and thanks :]

Answer
Dear Danielle,
Remove pretty much all of the sunflower seeds from her food; only give them to her as rare treats. Make sure you don't overfeed her. If you have one of those hamster ball let her run around in your room in it for at least 15 minutes a day. No more then that at one time, but at least that much throughout the whole day.