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Home > Cats > Is My Cat Too Underweight? Vet-Approved Ways to Tell if Your Cat is Too Skinny

Is My Cat Too Underweight? Vet-Approved Ways to Tell if Your Cat is Too Skinny

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Reviewed & Fact-Checked By

Dr. Paola Cuevas

Veterinarian, MVZ

The information is current and up-to-date in accordance with the latest veterinarian research.

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Most of the time, cat owners are advised to avoid overfeeding to avoid feline obesity. While obesity is more common, being underweight is also a cause for concern. It’s important for cats to be fed the right amount of healthy, nutritious food to remain at a healthy weight.

If you suspect that your cat may be underweight or losing weight, it’s important to consult with your veterinarian. Only they will be able to truly tell you whether your cat’s weight or weight loss is a concern and advise you on how to treat it, especially if there is an underlying disease affecting their weight.


How to Determine If Your Cat Is Underweight

There are a few tests you can conduct at home to help you determine if your cat is underweight.

  • Rub your hands along your cat’s sides to feel their ribs. If their ribs are very pronounced and easy to feel without pushing, it’s a sign that your cat could be underweight.
  • Feeling your cat’s spine is another way to determine if they’re underweight. A very pronounced spine isn’t present in cats who are at a healthy weight.
  • Determine your cat’s body condition score as outlined by the American Veterinary Association. A body score of below three on a five-point scale or five on a nine-point scale indicates that your cat is underweight and may require intervention.

These at-home tests can be used as a first-line in determining whether your cat is underweight or simply slender-built. If you find that your cat has a pronounced spine or ribcage, you should follow up with a vet to have them perform a more thorough exam.

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Image Credit: Piqsels

Helping an Underweight Cat

There are a few things you can do to help if you suspect that your cat is underweight.

The first thing you should do is monitor your cat’s eating. If they aren’t finishing their food or are suffering from appetite loss, this can indicate many things. Providing your vet with as much information as possible will help them come up with a long-term solution.

If your cat scarfs down its food and is looking for more, check to make sure you are feeding them the right amount of food. Different brands of cat food have different feeding requirements, so make sure they’re getting enough for their size, age, and activity level. If you’re in doubt, your vet can recommend the best cat food and feeding amount for your cat.

If you have multiple cats, it’s worth checking to make sure that your cat is getting all her food. Cat’s can be competitive at mealtime, and sometimes one cat doesn’t get to eat. Feeding your cats in separate rooms can help ensure that all of your feline companions stay healthy.

How to Help a Cat Gain Weight

If your vet has ruled out any underlying health conditions, there are several ways to help an underweight cat to gain weight.

  • Some cats simply need more food. They can be fed more meals per day or be given free access to dry food. Many cats prefer to “graze” throughout the day rather than eat larger meals at certain intervals.
  • As stated above, feed multiple cats separately, as one of them may guard the food and prevent your underweight cat from eating. Always make sure your cat can eat in a safe, non-threatening environment.
  • If your cat is shy or nervous, check to ensure their food bowl isn’t sitting next to a loud object that could scare them, such as a fan, an air conditioner, or the furnace.
  • If your underweight cat is eating dry kibble, try adding some wet food into their diet, or vice versa.
  • Sometimes cats are finicky about their food. Trying a different flavor or brand might be what your cat needs to improve their caloric intake. Changing protein sources can also be a good idea to rule out any digestive upset and food sensitivities that may be causing your cat not to eat.
  • Invest in a good quality fish oil and add the recommended amount to their daily schedule. This will increase the daily calories and provide additional health benefits.
  • Heating cat food in the microwave for a few seconds can make it smell better and be more appetizing.
  • Adding some water or unsalted chicken broth to your cat’s food can also make it more appealing.

Some cats have a higher metabolic rate than others and simply need more calories in their food. Senior cats also sometimes need senior food that is more easily digested than regular adult cat food.

Complement this information by using our cat calculator tool here:

The exact amount of calories an individual animal needs to maintain a healthy weight is variable and influenced by many factors including genetics, age, breed, and activity level. This tool is meant to be used only as a guideline for healthy individuals and does not substitute veterinary advice 

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If you think your cat is underweight, it is important to consult your vet to make sure they simply need more calories in their diet and that there isn’t an underlying illness that’s causing their weight loss. If your cat simply isn’t getting enough food, there are several steps you can take to increase their intake and make their food more appealing.

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Featured Image Credit: Benchamaporn Kanlapungha, Shutterstock

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