5 Reasons Why Your Cat May Be Losing Weight

Many cat owners are worried that their felines are too fat – but what do you do if your kitty is losing weight unintentionally?

Keeping an eye on your cat’s weight is an important step you can take to ensure he’s healthy. If you notice that your feline friend is losing weight, whether he’s eating normally or not, you should have him examined by the vet, as weight loss could indicate an underlying medical concern.

Below are a few, but not all, of the reasons why your cat may be losing weight. Just remember that your vet is the only one who can properly examine your kitty and determine whether your pet’s weight is ideal, too high, or too low, and what could be the cause for any weight loss that’s occurring.

Related: How Much Should I Feed My Cat?


Diabetes is one condition that causes weight loss, which is also often accompanied by a change in the cat’s appetite. If you notice that your cat has lost weight but is also showing other signs associated with diabetes, such as urinating more than usual, drinking more than usual, behaving sluggishly, or having bad breath that smells sweet, take him to the vet to be examined.


Your cat may stop eating and start to lose weight, even if he’s otherwise healthy, because something is wrong in his mouth, such as a toothache that’s causing him pain when he tries to eat. If you notice your cat pawing at his mouth or drooling, these could also indicate that there’s a tooth problem that needs to be checked by a vet.

Related: What To Do With Your Overweight Cat


If your kitty has a good appetite and is eating quite a bit, or perhaps even eating more than usual, but is still losing weight, hyperthyroidism might be the culprit. Other symptoms of this condition include, but are not limited to, diarrhea and vomiting, and it can also lead to heart ailments and death, so getting your kitty to the vet is imperative.

Gastrointestinal Ailments and Intestinal Parasites

Gastrointestinal problems, such as inflammatory bowel disease, infections, and food allergies, can lead to weight loss. Other symptoms may also be evident, such as vomiting, diarrhea, and a lack of appetite. Your vet will be able to determine if there’s something going on in your kitty’s gastrointestinal tract and, depending upon the diagnosis, will prescribe the appropriate treatments and dietary changes.

Another reason that your cat may be losing weight is intestinal parasites, which might also cause other symptoms, such as vomiting, bloating, and diarrhea. Cats who go outside and hunt down wild prey, such as rodents, are more prone to getting parasites, so it’s best to keep your kitty inside your house at all times. If your cat does have parasites or worms, your vet will prescribe medications to get rid of them.

When It’s Not Health Related

Your cat’s weight loss may not be due to a medical condition; instead, it might be due to a poor feeding location, dirty bowls, a picky palate, or stress.

If you feed your cat dry food, store it inside an airtight container, as doing so will help keep it fresher longer. And if you’re feeding wet food, wash the bowl after every meal.

It’s also a good idea to have the feeding area a good distance away from the litter box. Your cat should be able to eat in peace, so choose a quiet area where your pet won’t be prone to stress or anxiety.

If you have more than one cat in your family, make sure that everyone eats the appropriate amount of food. One kitty may get a little selfish and eat his share as well as his sibling’s share, causing weight gain in one cat and weight loss in another.

Sometimes cats get tired of a particular brand or flavor of food, so you may need to switch things up. If you have any questions regarding what you should be feeding your pet, talk to your vet. It’s also recommended that you transition your kitty to a new food gradually.

Just remember that weight loss isn’t always sudden or obvious, as it can occur gradually, so regularly weighing your cat is a great way to track how he’s doing. Talk to your veterinarian about what your particular kitty’s weight should be. Your vet will also be able to provide you with valuable advice regarding how much you should be feeding your cat, how often you should provide meals, and what foods will help keep your pet in the best shape possible.

Lisa Selvaggio
Lisa Selvaggio

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