Confusing weights

[SunnyOy]

Hi there!

My 2 male hamsters(almost 12 months old) recently has gained quite amount of weight. Myachick has grown from 169g to 173g over this month and Dumpling has grown from 151g to 156g. I changed their diet by purchasing new food packages and I can notice very obvious weight gain by simply placing them in my hands.

Is it normal that they are still growing at this speed around 1 year old? Is the food healthy to eat? Any bad consequence after growing too much weight? Should I limit their food supply?

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