Kitten food vs cat food: What’s the difference?

Two kittens eating
(Image credit: Getty Images)

Weighing up whether to purchase kitten food vs cat food is a common dilemma for a lot of pet parents. You may have both an adult cat and a kitten in your family and are wondering if there’s any harm feeding them both the same diet. Or, perhaps you’ve dashed into the grocery store and found the senior cat food section empty and only kitten food remaining.

In moments like these, many of us who have feline furkids find ourselves thinking that it would be a lot less fuss if we could just feed kittens and cats the same meals. After all, both cat food and kitten food is highly nutritious, so surely no matter what option we’re serving up, they’ll be getting a healthy and delicious dish, right?

Well, yes and no. While it’s true that both adult cat food and kitten food comes jam packed with all the vitamins, minerals and antioxidants your fur baby needs to thrive, the ratio of these, as well as how much protein and fat a dish has, is very much determined by the age and stage of our feline friends.

Although feeding your kitten cat food or your cat kitten food on a one off occasion is unlikely to do any harm, it’s best to stick to giving your feline friend a dish that’s been specially formulated to meet their needs. Below, we explain the differences between kitten food and cat food and dive into the drawbacks of feeding the wrong food to your fur baby.

Kitten food vs cat food: What’s the difference?

When you’re perusing the shelves of your local grocery store, you’ll notice that both kitten food and cat food comes in a wide range of flavors and textures with both wet and dry options available. But while on the surface they look very similar, what’s going on inside those bags and cans is actually quite different.

One of the biggest differences between kitten food and adult cat food is the proportion of protein and fat that each one contains. The recommended dry matter protein range for healthy kitten growth is 35-50% while the dry matter fat content should be between 18-35%. For adult cats (those over the age of one) a protein content of around 30-35% on a dry matter basis is suggested with 20-24% fat. Kittens need up to three times more calories than adult cats to fuel their rapid growth, which the extra protein and fat provides them with.

You’ll also find that kitten food has a higher ratio of certain vitamins and minerals than adult cat food does. Minerals like calcium and phosphorus are crucial to your kitten’s development, but these higher levels aren’t good for adult cats whose bodies are no longer growing.

cats eating out of food dishes

(Image credit: Getty Images)

Can you feed cat food to kittens?

While your kitten may look like a baby version of a cat, the reality is much more complex than that. Kitten’s need far more nutrients and calories than adult cats do to help their bodies to grow and develop. 

A kitten’s nutritional needs are very different from their bigger brothers and sisters, so it’s vital that you feed them a diet that has been specially formulated to meet these needs until they reach the age of one.

During these first 12 months, kittens expend huge amounts of energy, not just on growth but also on play. They need a lot more calories than adult cats to support all this energy expenditure, something that adult cat food doesn’t provide.

Cat food also tends to be lower in DHA, an omega-3 fatty acid that supports brain and vision development in kittens and kitten food is also much higher in the vitamins and minerals needed to build a healthy immune system.

While there are some formulas on the market that say they’re suitable for all life stages, we recommend that if you’re wanting to opt for one of these (perhaps because you have both a kitten and an adult cat in your family) that you check with your vet first to ensure it has everything your little one needs. 

You can also take a look at our guide to which kitten food is best to get our vet’s take on choosing the most appropriate diet for your little one. 

Can you feed kitten food to cats?

Cat eating out of pink bowl

(Image credit: Getty Images)

Adult cat food is geared towards one of two things: either maintaining health or providing extra support for certain health issues that a cat might be experiencing. The ratios of fat, protein, vitamins and minerals are all focused on maintenance as opposed to growth and the dish overall will be far lower in calories than kitten food to prevent obesity.

The good news is, that if your adult cat consumes kitten food occasionally, it won’t do them any harm. Unlike kittens, who miss out on vital nutrition when they eat adult cat food, an adult cat gobbling down kitten food won’t be putting their health at risk if they’re only being fed these dishes for short periods of time.

That being said, kitten food is at least 30% higher in calories than adult cat food, so if you were to feed your cat kitten food on an ongoing basis, they’d quickly start packing on the pounds. Your cat’s body will do a good job at expelling all the excess vitamins and minerals from kitten food that they don’t need, but the additional calories will definitely lead to weight gain. 

When to switch from kitten food to cat food

Knowing when to make the switch from kitten food to cat food can be challenging as different breeds reach maturity at different ages. Most cats are considered to be kittens until around 12 months of age, but for some bigger breeds, like the Maine Coon, it can take around 18 - 24 months for them to reach adulthood.

As with all important decisions surrounding your furry friend, we recommend you consult your vet who will be able to help guide you as to when to transition your kitten over to adult cat food and how to do so safely. 

Struggling to know when to transition your kitten to adult cat food? Our guide to ‘how long should cats eat kitten food for?’ has the answers.

Kathryn Rosenberg
Freelance writer

Kathryn is a freelance writer who has spent the past three years dividing her writing time between her two great loves - pets and health and wellness. When she’s not busy crafting the perfect sentence for her features, buying guides and news pieces, she can be found hanging out with a very mischievous Cocker Spaniel and a super sassy cat, drinking copious amounts of Jasmine tea and reading all the books.