Sofia is obese since the spay

My cat Princess Sofia is very obese. She is only 1.5 years old. I have a 2 year old male(neutered) and he is fine. She eats everything and will knock the garbage down to scrounge. I separate the food. I have to supervise because she will push Sir Winston out of the way to eat his food..He lets her do this. He will even try and get the treat bag from the cupboard for her (she is too fat to jump up on the counter) He is an enabler!! I have bought diet food. It is almost summer so I hope exercise will help. I dont want her getting diabetes or other diseases. This happened when she was spayed. She is a very small cat and about 14 lbs. I figure she is about 5-6 lbs overweight..Any suggestions?

[nancyjac]

Spaying does not cause obesity, increased food intake and decreased exercise causes obesity.  Put the garbage can where she can't get to it.  Eliminate the treats all together.  They have little or no nutritional value and just add extra calories.  If you allow your male cat on the counters, feed him there, so she can't get to his food.  Reduce her caloric intake gradually.  Suddenly cutting her intake drastically could cause other problems.

[Serenity38]

Thanks Nancy, I just dont want her to get diabetes..I have had cats my whole life and have never had this problem..It just makes me wonder what is being put in their food (ours too as us humans seem to be having an obesity epidemic) and if a filler is actually causing weight gain..I hope this summer she plays more and maybe doesnt get so hungry..She inhales her food and will puke because of it. She doesnt even crunch the food..