Why is my cat gaining weight despite no changes in food or exercise?

The first thing I would ask myself in these sorts of situations is if there is ANY POSSIBLE WAY he is getting food from any other sources. This can include other people, hunting, scavenging on the ground, the garbage, etc etc. If this is not possible, then he may just have a slower metabolism that a cat normally would for this young of an age. You are right in saying that hypothyroidism is rare in cats, to the point where I have not really ever met someone who has diagnosed this without the help of a surgical complication. There are other metabolic disorders and organ dysfunction that can result in weight gain, all of which would require further investigating with your regular veterinarian or through an internal medicine specialist. Hope this makes sense.

If he gained, he's still taking in more calories than he is expending. Discuss decreasing amounts fed with your veterinarian. Adjust the diet accordingly. Increase Oscar's activity if possible. This can be done through interactive play and toys.

Exercise is definitely a good way to help him lose weight, but make sure you do it at his pace and don't push him too much. The most important thing you can do to control the weight is control his nutrition. Knowing how to feed George properly is an important first step. I've put a couple of links below that have good information about feeding cats to prevent obesity and information about obesity. http://www.vet.cornell.edu/fhc/health_information/brochure_feedingcat.cfm http://www.vet.cornell.edu/fhc/Health_Information/obesity.cfm The next step is knowing how to implement a diet. This is often the most difficult thing for owners to do, but I can't stress enough the importance of sticking with the diet. Below is a link to information about getting your cat on a diet. http://www.petmd.com/cat/nutrition/evr_ct_obesity_in_cats_and_what_to_do_about_an_overweight_cat It is best to have George examined by a veterinarian, because it is possible that he has medical condition like hypothyroidism or diabetes that could be causing the obesity. The vet can also help to formulate a diet plan specifically to your cat. Weight loss plans often take a long time to work in cats, so don't be surprised if it takes a year or so to get her slimmed down. I hope that helps and George does well on the diet.

I see what you mean about the fur loss. I'm wondering if his belly getting fat is because he doesn't go outside anymore. When he was outside, he would have been more active, burning more calories. Because he lives indoors now, he won't be as active, so he won't be burning as many calories, leading him to gain weight. You should speak to his vet about cutting back his food to help him lose weight. The fur loss may be normal, my cat's belly looks just like that as well but I'd still have it checked out by a vet to be safe. I hope this helps.

Good on you for being concerned about LuLu's weight and wanting to get it down! It sounds like you are doing things right by giving her exercise and measuring out her food. I'm wondering if she is allowed outside or if you have other pets in the home? She could be stealing food from other pets in the home, or she goes outside, she could be visiting other homes for food. I would have her seen by a vet, as she may need a prescription food that will help her get the weight off. While the weight should be lost slowly, I would expect that after three weeks you would see some loss by now. Speak with your vet about a prescription weight loss food for her. I hope this helps!

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.

Gaining so much weight all of a sudden could be a sign of metabolic disease or an endocrine disease such as diabetes. She may feel ill and vulnerable and therefore tries to keep the other kitties away from her. Please take her to your vet ASAP for an exam and blood tests.