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The Skinny on Weight Loss in Cats

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exotic shorthair colorpoint cat standing atop a bathroom scale

Has your purring puffball slimmed down unexpectedly? There are a bunch of reasons why cats lose weight suddenly, such as stress, illnesses, or just as a natural part of the aging process. If you’re concerned about your cat’s thinning waistline, it’s a good idea to get to the veterinarian to help identify potential issues sooner rather than later.

Identifying Cat Weight Loss

If you’re taking your cat in for annual wellness exams (which every cat parent should be doing!), your veterinarian will keep track of how much your cat weighs over time. This is the best way to tell if your cat’s weight is becoming an issue—whether it’s weight gain or weight loss.

It would help if you also asked your vet what a healthy weight and build is for your cat. There are many different breeds of cats with many different body types—from thin and svelte to stocky and muscular—that it can be tough to tell without a bit of expert advice.

Do a Home Health Check

Cat weight loss can happen gradually, which makes it more difficult to notice. A regular home health check can help you keep an eye on your cat’s weight and overall health. Take a few minutes once a week to look your cat over for any physical changes or concerning symptoms, like weight loss, discharge from the eyes or ears, or gum inflammation.

During this home health check, you should rub your cat gently down the back and sides to get a better handle on their weight. Don’t rely only on a sight check, particularly if your cat has long hair. All of that extra fluff can mask your cat’s actual weight.

Remember, too, that cats tend to mask or hide their symptoms. If they’re not feeling well, they may hide by napping in the back of your bedroom closet or leave the room when you come in. This makes a regular home health check even more important.

Make Note of Eating Habits

Another way to tell if your cat might be losing weight is to take note of eating habits. Do they hide during mealtimes? Are they leaving food behind when they normally clean their plate? Are they turning their nose up at treats or other goodies, like bits of tuna or turkey, that they would typically devour? These can all be signs that your cat isn’t feeling well, which could result in weight loss.

gray domestic shorthair cat with a red collar and tag

What Causes Weight Loss in Cats?

Cat weight loss is often caused by illnesses or anxiety, but it may just be that your cat doesn’t like something about the way meals are being served. So, before you get too worried about a stressed out or sick cat, you can start with these questions:

  • Is the food bowl clean? You wouldn’t want to eat lunch off a plate with bits of breakfast still stuck to it, either.
  • Is it easily accessible? If you have an older cat, especially one that suffers from arthritis, you may need to raise the food bowl off the floor so they can eat without discomfort.
  • Is it too close to the litter box? Nobody would want to eat too close to the bathroom.
  • Is there a lot of noise during mealtimes? Maybe your cat likes a quiet respite to better focus on the yummy meal at hand.

If the problem seems to go deeper than just a dirty food bowl, the weight loss may be due to changes around the house or an underlying illness. In any case, it’s good to get your vet’s perspective on what might be going on.

Changes in the Home

Like many of us humans, cats tend to like their routines. If something has changed in your home, like your energetic kids are now home from school for the summer or a new baby has arrived, your cat might become anxious and stop eating. Changes like moving to a new house or apartment, getting another pet, or leaving them with a pet sitter while you go on vacation can also be stressful for a cat.

If your cat’s weight loss is due to some routine change, the answer may simply be to give your furry friend some time to adjust to the new situation. If the issue doesn’t seem to be resolving itself, you should take your cat to the vet since there could be an illness at the root of the problem. Your vet may also recommend medication to help your cat get acclimated or get through the transition more smoothly.

Just a quick note on cats and medication—please never, ever give your cat any medication without speaking to your vet first. Cats are super sensitive to over-the-counter and prescription medications. Even a small dose of Tylenol or a sleeping pill can be fatal. If you need to give your cat medicine prescribed by your vet, don’t miss these tricks to help that pill go down.

Cat Illnesses

Cats tend to hide or mask symptoms when they’re not feeling well, and weight loss is up there on the list of 5 Signs Your Cat is Sick. Your cat could be suffering from an upset tummy after eating something that didn’t agree with them or, a food allergy could cause it. Stomach issues can also be related to serious illnesses, like diabetes, hyperthyroidism (in which case your cat would be losing weight despite a healthy appetite), or cancer.

Parasites, such as roundworms, are another common ailment that can cause weight loss. Cats who have problems with their teeth or gums, such as a fractured tooth or inflamed gums due to gingivitis, may also have a tough time chewing up their food which can cause weight loss.

What Cats are at Risk?

Weight loss can occur in any cat, from Domestic Shorthairs to Calico Cats, but it can be more prevalent in older cats who are more prone to illnesses. Older cats may lose weight as their nutritional needs change with age. If you have a senior cat, you should ask your vet for specific dietary recommendations. Your cat might benefit from additional fiber or other nutrients to help maintain a healthy weight.

black cat licking lips next to a full bowl of food

Diagnosing and Treating Cat Weight Loss

Veterinarians have a lot of diagnostic tools to help figure out why cats are losing weight. For instance, a nose-to-tail physical exam, blood work, urinalysis, and other tests can help pinpoint the problem. However, these tests may not always uncover the underlying cause of weight loss in cats. This isn’t necessarily bad since the issue may get resolved as the cat is encouraged to put weight back on.

If an illness can be determined, the specific ailment will need to be addressed with medication or other treatments. Changes in diet may also be recommended to help cats regain weight. In more dire situations, cats may be put on a feeding tube or prescribed an appetite stimulant.

Cat insurance can help you manage the costs of treatment for conditions that cause weight loss in cats. It can also cover other illnesses, accidents, and the routine preventive care (for an additional cost) your cat needs.

Healthy Weight Tips

Cats can’t go into the fridge or pantry to fix their dinners, so it’s up to us cat parents to make sure they have a healthy diet. Talk to your vet about what and how often you should feed your cat. Generally, set mealtimes are recommended as a healthier option than just leaving food out for your cat to graze on. Here are some basic guidelines:

  • Adult cats should get two meals a day spaced eight to 12 hours apart.
  • Kittens three to six months old should get three meals a day.
  • Little kitties six to 12 weeks old should have four meals a day.

Be sure to throw away any leftover canned food after 30 minutes.

Cat Treats

Cats love treats but don’t go overboard. Most packaged treats contain a lot of fat and sugar, which can cause weight gain. You can also try offering your cat fresh fruits and veggies, like broccoli, corn, or cantaloupe, as an occasional treat. Check out our Infographic of pet-friendly fruits and veggies for a few ideas.

And, just a reminder, treats should not make up more than 10% of a pet’s caloric intake.

The information presented in this article is for educational and informational purposes only and does not constitute or substitute for the advice of your veterinarian.


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