BIG hamster...

Question
i have had them around 3 weeks, almost a month. My other hamster looks fine and doesnt have any symptoms. Probably my other hamster is just a fatty[sadly]. But they do have a big difference. I was wondering if i should change their food to this kind with big clumps instead of wasting the small pieces of food they don't eat. Should i do this?
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The text above is a follow-up to ...

-----Question-----
i adopted 2 hamsters a while ago and the first hamster i had was a short haired teddy bear hamster. It was normal sized and healthy. The second hamster i got was a long haired teddy bear hamster. It was as big as my first hamster when i got her. [i got that at a week apart]. Now my short haired hamster is huge compared to my long haired hamster after of leaving them to my cousin for a week due to a trip. My 2nd hamster is always in the small house thing and it brings food inside. I'm not sure if my 1st hamster was overfed or something. My cousin was saying it might be pregnant but i doubt that. [both females] What should I do. Sorry for the long question
-----Answer-----
how long have you had the hamsters? if you've had them for a month than she isn't pregnant just a fatty. How is your second hamster doing? Is she eating okay, does she have a clean coat and is her bottom clean as well?

Answer
having a fatty hamster is a good thing. Mine is a fatty too. If you want to switch food then that's fine. My hamster has two different types of foods because he likes the small and medium size pieces, but hates the large pieces. They are always going to waste food and not eat it all, you just gotta find out what they like to eat and then buy the food that has a lot of the stuff they like.