Watermelon isn't toxic to cats, but that doesn't mean it's a good idea to add it to your pet's diet.
cat eating watermelon
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Watermelon is the ultimate healthy and refreshing summer treat—at least for humans. If you’re curious if your cat can eat watermelon, the answer is yes! Watermelon is generally considered to be safe for cats. But before adding the fruit to your cat’s diet, learn a bit more about whether it’s really a healthy treat for your kitty and if there are any precautions you need to take to feed it to her safely.

Are There Nutritional Benefits to Feeding Cats Watermelon?

Cats have specific nutrient requirements that must be met by their diet, and the nutrients they require aren’t the same that we humans need. “Cats don’t have a minimal daily carbohydrate requirement, and watermelon is fairly high in carbohydrate content,” Theresa Entriken, DVM, a veterinary consultant based in Leawood, Kan. says. 

As obligate carnivores, cats rely on nutrients found only in animal products. “The simplest and most convenient way to meet the nutrient requirements of a cat,” the Clinical Nutrition Service at the University of Missouri Small Animal Clinical Nutrition Service in Columbia, Mo., explains, “is to provide them with a complete and balanced commercial diet formulated by a board-certified veterinary nutritionist or an individual with a PhD in animal nutrition.” 

This means that as long as your cat is getting all of his required nutrients from his diet, treats like watermelon aren’t necessary. And when it comes to nutrients, more isn’t always merrier. In some cases, giving a cat more nutrients than he needs can actually cause problems.  

So Watermelon Doesn’t Provide Nutrients, but Will It Harm My Cat?

Although watermelon is not considered poisonous to cats, there are some watchouts to feeding it to your cat.

First, watermelon is considered to be safe for healthy cats. So if your cat has a health condition (such as diabetes), it’s better to avoid watermelon, because simple sugars such as those found in watermelon are easily digested and absorbed, Entriken says. 

Second, remember that every cat is unique. Their reactions can vary a great deal when it comes to tolerating certain foods. “Cats must be considered individually,” the Clinical Nutrition Service explains, “as some cats may consume a particular food item with no issue and another cat may consume the same item and develop vomiting, diarrhea, or other adverse signs.”

Third, the majority of your cat’s calories should come from foods specially formulated to give him the nutrients he needs. Human foods like watermelon should only be given occasionally and in moderation.  

How Can I Feed My Cat Watermelon Safely?

Taking into account the caveats above and feline nutritional needs, the following guidelines offer steps to safely feed watermelon to your cat:

  • Ask. Talk to your veterinarian before giving your cat any new human foods—even if they’re typically considered to be safe for pets. 
  • Calculate. To determine how much watermelon is safe for your cat to eat, you’ll need to do a little math. The Clinical Nutrition Service says treats shouldn’t account for more than 10 percent of your cat’s daily caloric intake. For example, if your cat eats 250 calories a day, only 25 of those calories should come from treats. According to the U.S. Department of Agriculture, one cup of watermelon is around 45 calories. Cats vary in the amount of food they need to eat each day to maintain an ideal weight. If you aren’t sure how many calories your cat needs or what his ideal weight is, visit with your veterinarian about developing a nutrition plan that’s specific to your cat.
  • Prepare. Thoroughly wash the watermelon with water before cutting a section into pieces that are easy for your pet to manage. Tiny bites, about the size of your cat’s kibble are best. Remember to remove the seeds to avoid gastrointestinal irritation. And avoid giving your cat the rind, as well, as it can be hard for him to digest.
  • Monitor. The Clinical Nutrition Service says that even safe foods can have unexpected reactions, so watch your pet for signs of gastrointestinal problems (e.g. vomiting, diarrhea) after consuming a new food. It’s also a good idea to introduce only one new food at a time. That way, if your cat does start showing signs of illness, you can more easily pinpoint the source of the problem. If you think your cat is having an adverse response to watermelon, call your veterinarian. 

So Should Cats Eat Watermelon?

Just because your cat can eat watermelon as a treat might not mean he should. The bottom line, as with any treat, is that nutrients should come first. Because watermelon isn’t a part of a complete and balanced diet for felines, there’s no need to go out of your way to get your cat to eat it. “Most cats aren’t attracted to sweet-tasting foods, and would prefer chicken or fish to watermelon,” Entriken says. However, if your cat is curious and meowing for a taste, following the guidelines above is the safest way to respond to his cravings. 

If you’re unsure whether your cat is getting the nutrients he needs from the food he eats every day, bring up your concerns with your veterinarian. They are ready to help you find good options for your pet. And if you’re sensing a theme about going to your veterinarian with questions, it’s intentional. Open, honest communication with your veterinarian is key to keeping your cat safe and healthy. No problem (or treat!) is too small to discuss.