Re: My cat wants to eat every 2-3 hours...
I've actually read that it's 15 calories/pound for a very inactive cat up to 25 calories/pound for a very active cat (when I researching diabetic diets in cats).
You have a 20 lb pound cat, so feed her the amount of food for a 19 lb cat. The weight loss needs to be slow and consistant, so she loses fat and not muscle. Once she reaches 19 lbs, start feeding her like she weighs 18 lbs. Weigh at least twice a week and record the weight.
There are several sites out there with info on the calorie count for various wet foods. Assuming that you don't have a cat with other health issues, aim for a lower carb, higher protein food. Cats are genetically designed for a high protein diet. There are a few dry cat foods that qualify as high protein, lower carb. Avoid wet foods with gravy - they are higher carb foods and should only be used as a treat.
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