My cat is overweight. Why is he gaining weight despite eating less?

I would recommend having some blood work performed on your cat. Hyperthyroidism is a common disease in middle aged to older cats that causes an increase metabolism so cats are often very hungry but unable to gain weight. I would also recommend having your vet check a fecal sample to ensure that Koda does not have any intestinal parasites as this can cause weight loss as well. I hope this helps. Thanks for using Petco Pet Education Center, formerly Petcoach. Best of luck.

Cats get hyperthyroidism and this actually causes them to get too skinny. Cats who are over weight at at a much greater risk for diabetes but if they get the disease, they tend to lose weight and drink excessively. To answer your questions though, both conditions require blood work for diagnosis. Most cats get heavy because they eat too much and their metabolism slows down. Feeding multiple cats is difficult when one needs to lose weight and requires commitment on the humans part. You cannot leave food down all the time. You must separate the cats at feeding time. You must switch the heavy cat to a light cat food and control the portions. Cats do best if they are feed 4-6 times a day. For my own fat cat, I got an automatic feeder that stays shut in a room. It portion controls and is timed. All I do is open the door and shut it behind him. It’s pretty easy and I like that. I hope this is helpful and please feel free to post any additional questions.

Poor Canelo. I am sorry that it has been difficult to get him to gain weight. With him being young and petite and intact then I would not be too concerned. Of course, without doing an exam I cannot say this for sure. If he is really skinny and all of his bones are showing then yes, I would be more concerned. If his bones are not showing and you cannot see his ribs then I would be less concerned. Some cats are more petit and slender especially if they are very active and outdoors. I would also recommend to have him neutered as that may also help him gain weight. Finally, if he is really skinny and you are able to see his bones, I would recommend to ensure your vet tested his thyroid (high thyroid isn't common is young cats but possible). Then I would recommend to increase the amount of food you are feeding and if he is still not gaining weigh then the next step would be abdominal x-rays or ultrasound. I hope this helps some. I would love to talk to you more on the forum or if you would like to set up a consult.

If she eats very little but still gains a lot of weight it is not normal, she could be suffering from hypothyroidism which is an hormonal disease. you need to take her to the vet ASAP in order to have a blood test done first.

He probably just has a very slow metabolism. I do not know what brand of food you are currently feeding but you may need to switch him to a lower calorie food. If you would like to post again with the name of food you are feeding then we could probably help you better.

Weight loss coupled with a normal or increased appetite can be a sign of diabetes or hyperthyroidism, to name a couple of possibilities. I recommend getting Felix seen by your vet as soon as possible for an exam and labwork to determine the reason for his weight loss and get him started on treatment.

Since Fred is an older kitty it is likely he is suffering from an overactive thyroid. Kidney disease and diabetes can also cause this. I suggest you take him to your vet for an exam and a blood test. Hyperthyroidism is easily treated with thyreostatic medicine and is likely the most common cause for the weight loss.