4 for 3 on Purina® diets here


Can kittens eat cat food?

Brown kitten eating wet food advice
© Shutterstock

A balanced nutritious diet is what a kitten needs. But can he eat cat food during the early months, or does it cause him harm? Read on to find out.

By Nick Whittle

Updated on the 19/12/2019, 15:24

Kitten nutrition is about as important as it gets for the owner. To feed a kitten the right kind of food is to give him the very best start in life. His body needs calories, protein, fatty acids and vitamins to grow.

But surely cat food has those same nutrients and minerals? Unfortunately, it hasn’t, and that’s because pet food manufacturers known the nutritional needs of a small kitten are very different from those of an adult cat.

One of the biggest differences is the calorie content of cat and kitten food. Kittens need a lot of calories for their growing bodies and they should get most of them from protein. The protein itself is necessary for the growth of almost every type of cell in his body: from brain to muscle, to eye and to reproductive organs.


A post shared by Ragdoll Cattery (@happy_kingdom_ragdolls) on

To have sufficient protein in his early months will also prevent him from contracting some of the nastier conditions that adult cats are more prone to.

To feed a kitten cat food all of the time is therefore harmful because you not only deprive him of the important vitamins and minerals and fatty acids he needs to healthily develop but you also put him in the way of danger when he reaches adulthood.

How different is cat and kitten food?

Kitten food differs from adult cat food mainly in the amount of protein and fatty acids it contains. The amount of water, magnesium, taurine and other minerals does not differ as much.

Fats, such as the Omega-3 fatty acid complex, are essential for delivering fat soluble vitamins to your pet. Fats also provide extra energy, something all energetic young kittens need as they pass through this year of rapid growth.

Minerals promote the growth of strong bones and teeth. Calcium, phosphorus and potassium are critically important to your kitten's development.

Comparative ingredients of cat and kitten (dry) food

  • Protein: adult 30%, kitten 34%
  • Fat: adult 18%, kitten 20%
  • Fibre: adult 5%, kitten 3%

What else do young kittens need?

Mother’s milk is good up to a point, but there comes a time in every kitten’s life when the amount of nutrients contained within their mum’s milk is not enough to support a healthy development. It is at this point that kittens need to be weaned.

If you have been looking after a litter of kittens or have been hand-rearing a kitten the signs of your kitten’s wanting to be weaned will be apparent. The litter becomes less interested in mum’s teats and tries to steal some of her cat food; a kitten that is hand-reared starts to chew and nibble at the teat of his feeding bottle.


A post shared by Our Fostering Tails ? (@our_fostering_tails) on

These signals to wean appear at around four weeks. It could be earlier but it should not be later.

What happens if my kitten eats cat food by accident?

Don’t panic. If your kitten eats adult cat food by accident (and it is not unusual for him to do so), he won’t come to any harm. Make sure that your stock of kitten food is kept at a good amount to avoid finding yourself caught short on a public holiday or when all the shops are closed.

What would happen if I fed my kitten cat food all the time?

You should not be feeding him a regular diet of adult cat food until he’s at least a year old. Some folks think that once a kitten starts looking like a small version of an adult cat, it’s OK to switch to adult cat food. But even if your kitten looks like a miniature adult, he still has the nutritional needs of a kitten.

If you feed your older kitten a diet of adult cat food, he’ll need to eat more to get the nutrients he needs. Because of the higher fat content of the kitten’s food this could result in obesity. A more likely outcome would be that to have denied your kitten the nutrients and minerals of a proper kitten food will cause him to become malnourished.

With a diet lacking in essential minerals, vitamins and protein the kitten and the adult cat will suffer with one or more of the following symptoms:

  • Agitation and antisocial behaviour
  • Diarrhoea and weight loss
  • Dry and scaly skin and poor fur quality
  • Failing eye sight
  • Gingivitis
  • Impaired immunity
  • Muscular weakness
  • Overwhelming tiredness
  • Poor claw development
  • Poor coordination

Untreated malnutrition

Over time, if the malnutrition is neglected and you continue to feed your kitten cat food your kitten may become skeletal in appearance. The shoulder blades and spinal vertebrae will be clearly visible through the skin, and the bones will protrude. This is due to the wasting away or poor development of the kitten’s muscles.

The kitten’s stomach will shrink and become flat and the ability of his gut to absorb nutrients will lessen. Ideally, your cat must have a well-proportioned body, which is characterized by a visible waist behind the ribs and a small paunch of fat on their abdomen. Also, the ribs must be felt, but with a bit of fat covering them.

So if your cat’s ribs are too visible and he doesn’t seem to have any fat, this means that he is malnourished. Most importantly, you will notice an abdominal tuck, or the cat’s tummy appears sucked in. Moreover, his hip bones and spine may be very pronounced.

Also if you run your hands on his rib cage, you will feel minimal to no fat covering all over his body, especially on his tummy.

Organ failure can result from a prolonged period of malnutrition. The liver is also badly affected by malnutrition.

Metabolic impairment can lead to an extensive build-up of fat in the liver. This can result in hypoglycaemia accompanied by a decrease in insulin production and release by the liver. As a result, the liver can no longer carry out its routine functions. This condition is called Hepatic Lipidosis and results in fatality in 90 percent of cats affected by the condition.


A post shared by Sir Gilbert Rory (@sirgilbertrory) on

It’s very important to give your kitten a healthy and balanced diet, and it’s better to feed him commercial food that is specifically designed to be enjoyed by a kitten. Feeding your kitten some cat food once or twice in a month will not stunt his development but to make a regular thing of it will. Malnutrition can be turned around but the effect it has on cat’s immunity and general health are long-lasting.

Read also