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Fat Cats: How Big Is Too Big?

If Garfield taught us anything, it’s that felines can really put food away. While you might write off that extra pudge as “more to love,” the fact of the matter is that being overweight, even by a few pounds, is a serious health concern for cats. And unfortunately, over half of America’s cats are overweight.

How do you know when there’s a problem?


  • Go on and ogle your cat. Does your cat have an identifiable waist? There should be a difference between the ribcage and the midsection.
  • When looking from the side, its stomach should tuck under the rib cage instead of being protruding and round.


  • Your fingers should be able to feel your cat’s ribs easily.
  • Overweight cats will have fatty deposits at the base of their tails.


Your cat is tipping the scales when they are 20 percent above ideal weight. Most veterinarians will tell you that a cat with a body mass index of 42 or higher needs to trim down. Here are the steps to take to figure out your kitty’s BMI.

  1. Grab a tape measure and a calculator.
  2. Measure the circumference of your cat’s rib cage.
  3. Measure the length of the lower back leg from the knee to the ankle.
  4. Divide the rib cage measurement by 0.7062 and subtract the length of the leg.
  5. Divide that answer by 0.9156.
  6. Subtract the new number by the leg length, and there you have it!

What’s wrong with an obese cat, anyway?

Cats of a healthy weight can live up to 2.5 years longer than an overweight cat. Boom.

If that’s not reason enough, you should know that even a little extra pressure on a cat’s skin and organs can cause a smorgasbord of ailments. Feline obesity has been linked to diabetes, lameness, arthritis, heart and liver disease, bladder blockages and skin conditions.

How can you un-fat your cat?

(Not so) fun fact: Cat obesity can be genetic. But since that’s rarely the cause, you’re still on the hook for making your cat healthier. Dieting cats should only lose 1 pound per month. Here are some ways to achieve this.

  • Measure your cat’s food instead of eyeballing it, and count treats as part of their daily consumption.
  • Introduce new toys to spark their interest.
  • Keep your cat’s water bowl full. Drinking will often distract them from feeling hungry or scrounging for scraps.
  • Schedule daily playtime. 15-20 minutes a day will make a difference.
  • Take your cat to the veterinarian. They can help you make a plan and might even suggest that you add a lower-calorie food to your pet’s menu.
  • Weigh your cat to monitor what’s going on. It’s easy to do when you step on the scale together and subtract your own weight.

The information in this blog has been developed with our veterinarian and is designed to help educate pet parents. If you have questions or concerns about your pet's health or nutrition, please talk with your veterinarian.


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