How long should cats eat kitten food for?

how long should cats eat kitten food
(Image credit: Getty)

How long should cats eat kitten food for? It’s a question you may be asking if you have a little bundle of fluff who’s about to enter adulthood. Kittens require a specialized diet that’s been formulated to meet their nutritional needs and support healthy growth and development, but it’s important to transition to adult food when the time is right to prevent weight gain.

With the exception of large breeds, like the Maine Coon, most cats reach maturity around one year of age. This is generally viewed as the right time to switch your fur friend over from the best kitten food to the best cat food. Kitten food has a higher protein and calorie count than adult food and once your little one has stopped growing, they no longer require such a nutrient-dense diet. 

When switching from kitten to cat food, you’ll want to transition gradually over the course of 10 days to ensure your furbaby doesn’t suffer from a stomach upset. A cat's digestive system is home to lots of bacteria and yeast that help them to digest their food and bolster their immune system, so it’s important to give these gastrointestinal microbes time to adjust.

To help you figure out when to make the switch and how to choose the right food for your adult feline friend, we spoke to Dr. Joanna Woodnutt to get her expert tips. Check out our guide to kitten care tips or read on to find out what she had to say…..

Dr Joanna Woodnutt BVM BVS BVMedSci MRCVS
Dr Joanna Woodnutt MRCVS

Dr Joanna Woodnutt qualified as a veterinarian from the University of Nottingham where she then went on to practice companion animal medicine in the Midlands. She really took to the consulting side of things and helping clients with medical problems such as dermatology, behaviour and nutrition - anything that involved helping clients understand their pets better.

At what age does a kitten become a cat?

"Deciding when a kitten becomes a cat isn’t simple – like humans there are many ways to look at maturity, and they don’t necessarily give the same age as a result," explains Woodnutt. "Having said that, most people consider the one year mark to be around the point a kitten turns into a cat. In some cases, cats aged 6-12 months could be considered adult, as in most breeds they’re almost fully grown and sexually mature. However, a year tends to be the established age when a kitten turns into a cat."

As with all animals, there are some exceptions, which include larger breeds like the Maine Coon. These cats tend to reach maturity between 18 months and two years of age. 

When can kittens eat dry food only?

Most vets recommend a dry and wet food diet, as cats tend to under-consume water, and wet food can help keep them hydrated. Speak to your vet to ensure a dry food-only diet is appropriate for your kitty. If that's the case, kittens can start to have the best dry cat food at around three to four weeks, but they are fully weaned from their mother's milk by six to eight weeks and can eat just kitten food.

When to switch from kitten to cat food

During their time as kittens, cats often feed on small amounts of food frequently throughout the day. As they get older and mature into full-grown cats, this tends to change to eating just two meals a day - and what they eat should change, as well. 

"Most cats can be safely transitioned to adult cat food once their growth has stopped. In most breeds this will be around 9-12 months of age," advises Woodnutt. "In giant breeds, you may need to leave them eating kitten food until 18 months to ensure they reach their full potential – your veterinarian will be able to advise for your individual cat. Your veterinarian may also advise feeding adult cat food to your kitten once he or she has been neutered, as neutered cats are prone to excessive weight gain and don’t need the extra calories the kitten food provides."

It's important to make the transition at the right time as cat food is different from kitten food. The latter is higher in calories and contains essential nutrients that will help your kitten grow. If an adult cat eats kitten food, they'll be getting way too many extra calories in their diet, which could cause them to pile on the pounds. And kittens can't eat adult cat food, as it doesn't include the vital nutrients they need. 

To avoid intestinal upset, such as diarrhea in cats, it's best to slowly swap over from the kitten food to the adult food over a few days. Consult your veterinarian for the best way to portion out the food, but it's usually a ratio of 75/25 kitten to cat food, then 50/50, then 25/75, then 100% adult formulation. 

If you were to instantly change what they eat without a gradual introduction, this has the potential to cause your cat to experience stomach upset or even trigger them to go on hunger strikes (yes – they can be that fussy and stubborn!). 

Choosing the right food for your adult cat

"There are lots of things to consider when choosing a cat food," explains Woodnutt. "The majority of cats will do fine on the majority of diets, as long as they ‘complete and balanced’ and designed for the right life stage – I.e for adult cats. There are of course some cats that will benefit from a more specialized diet. For instance, you might want to choose a diet without certain ingredients due to allergies and intolerances, or a diet designed for cats with medical conditions like kidney disease. Your vet will always be willing to talk about your cat’s diet options and help you find a diet that’s right for your feline family."

It’s important to find the best cat food that offers your feline the same high-quality nutrition as their kitten food used to. For happy and healthy adult cats, you should consider the following things:

  • Have high-quality ingredients been used to make the food?
  • Does it provide a complete and balanced diet with appropriate levels of protein, fat, fibre, vitamins, and minerals?
  • Has the brand met or exceeded the regulatory standards?

No matter what the packaging says, your cat will in fact be the best indicator as to whether a particular type of food is purr-fect for them. Be sure to look out for:

  • Bright eyes and clean teeth
  • Small, firm, stools
  • A shiny, luxurious coat
  • Healthy skin
  • Exceptional muscle tone

Foods to avoid giving your feline

Cats eat kitten food

(Image credit: Getty)

"It’s not a good idea to feed cats human food in general. More than half of cats are overweight, and human food is often more calorific than we realise," Woodnutt advises. "What is ‘a tiny cube of cheese’ to us is actually a large portion of our cats’ daily calorie allowance. That said, there are some things that definitely shouldn’t be fed to cats,  these include things like: 

  • Onions
  • Garlic
  • Chocolate
  • Any foods containing the ingredient Xylitol

It's also best to take precautions when it comes to raw meat or liver, which can contain harmful bacteria, and raw eggs, which can lead to problems with their skin and coat. Similarly, raw fish can trigger a vitamin B deficiency, cause seizures, or be fatal, and milk can cause diarrhea. Read five human foods that are poisonous to cats to learn more.

Choosing the right diet for your kitten at every stage can seem daunting, but this article should have helped answer any questions you might have. Remember that cat food and kitten food are different things and it's important to feed your cat the appropriate meal for their life stage. If you’re concerned about whether you’re feeding your little ball of fluff the right food, ask your veterinarian for advice. 

Enjoyed this piece and looking for more great kitty content? Then be sure to check out our guide to how often should I feed my kitten?

Chloe Petrylak

Chloe is a freelance writer, editor, and proofreader, who has more than ten years’ experience in creating animal-focussed content. From National Geographic to Animal Planet, Chloe’s passion for creating fact-filled features all about wildlife and the environment is evident. But it’s not just wild animals that Chloe’s fascinated by. Having written more than 75 articles for PetsRadar - and having her very own four-legged friend by her side - it’s no wonder that her love of dogs (and, of course, cats) has grown exponentially.  

Her website,, and social media pages - @ChloeMayWrites on Instagram, Facebook, and Twitter - showcase her knowledge through daily facts and trivia tidbits. For example, did you know that snails have teeth?! 

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