Feeding a Spayed or Neutered Cat: How Many Grams a Day Is Right?

Many pet parents notice that after their cat is spayed or neutered, they start eating more and their tummy slowly gets rounder. This is very common, so there is no need to worry.

Today, let’s talk about food for spayed and neutered cats: why they gain weight easily, how to measure their food, how to check their body shape with your own hands, and also water, play, and treats.

Why spayed and neutered cats gain weight easily

Appetite goes up after the surgery

Adult male cats that can eat as much as they like start eating more almost right after being neutered.

These cats gain about 20% in body weight within 6 months, and most of that gain is fat.

In female kittens spayed at around 7 months old, energy intake also rises quickly after surgery.

Hormones change, and so do energy needs

When sex hormones drop, the balance between appetite and energy use shifts.

Put simply, your cat wants to eat more but does not burn more energy. If you keep filling the bowl whenever they ask, weight can go up easily.

How many grams a day should a spayed or neutered cat eat?

An example from the feeding table on the bag

The right amount depends on the energy in each recipe, so check the feeding table on the bag of the food your cat is eating.

For example, the bag of Deserve adult cat dry food (1 year and up) has a table with separate amounts for spayed/neutered and intact cats.

You can see that for cats of the same weight, the recommended amount is lower once they are spayed or neutered.

These numbers are only a starting guide from the bag. Adjust them to your cat’s actual body shape, because label advice is based on typical cats, and every cat moves a different amount.

Measure accurately: a scale works best

• Weigh food in grams instead of guessing with a cup.
• Split it into meals, for example 2 meals a day for adult cats.
• Avoid leaving food in the bowl all day, as this is a major cause of weight gain in cats.
• In multi-cat homes, try feeding each cat in a separate spot.

If your cat also eats wet food, remember to count it in the daily total.

Check your cat’s body shape at home

The number on the scale does not tell the whole story. Vets often use a 9-point Body Condition Score, where a score of 5 is ideal.¹

Check these 3 points:

1. Ribs Run your hands along their sides. You should be able to feel the ribs under a thin layer of fat.
2. Waist Looking from above, you should see a slight waist behind the ribs.
3. Belly Looking from the side, there should be only a little belly fat.

If the ribs are hard to feel, the waist is hard to see, and the belly is getting round, your cat is starting to go above their ideal shape.

Weigh your cat and check their shape about once a month, and write it down. If they are getting heavier, reduce their food little by little and talk to your vet.

Don’t forget water

Water matters for many systems in your cat’s body, including temperature control and digestion.

Roughly, a cat weighing about 4.5 kg needs about 1 measuring cup of water a day.² Cats that eat wet food may drink less water, because they already get water from their food.

A few small tips:

• Place clean water in several spots your cat often walks past.
• Try a cat water fountain. Some cats prefer running water.
• Add wet food, or add water to their food.

Play every day to help burn energy

Many indoor cats spend most of their time eating and sleeping, so play helps get them moving.

• Use a wand toy or a toy that moves like prey.
• Set up a cat tree so your cat can climb.
• Try a food puzzle toy (puzzle feeder), starting with an easy one.
• Hide some of their food around the house so they can go hunting.

Treats are fine, in the right amount

Treats should be no more than 10% of your cat’s daily energy intake.³ For example, if your cat gets 300 kcal a day, treats should be no more than 30 kcal.

Deserve cat treats such as Purrfect Puffs (for cats 3 months and older) provide 1.8 kcal per piece, and should be counted in this allowance too.

When to see a vet

• Weight goes up or down unusually fast.
• Your cat loses appetite, seems dull, or is weak.
• If you want your cat to lose weight, let a vet make the plan.

Most important: never starve your cat to make them lose weight. Cats that suddenly go without food are at risk of fatty liver disease, which is very dangerous.

Weight loss should be gradual, about 1–2% of body weight per week, under a vet’s care.²

Summary

Spayed and neutered cats gain weight easily because they want to eat more but do not burn more energy.

You can help by measuring food using the spayed/neutered table on the bag, checking body shape regularly, providing enough water, playing every day, and keeping treats under 10%. If you are not sure, you can always ask your vet.

Frequently asked questions

References: WSAVA, Cornell Feline Health Center, VCA Animal Hospitals