Can Kittens Eat Adult Cat Food? (When Can Kittens Eat Wet Food)

For many people when it comes to kittens, the idea is that they're just smaller and less experienced versions of cats. And while that's true to some extent, there are some crucial differences you need to keep in mind. Probably one of the biggest differentiating cat health factors between kittens and adult cats is their nutritional needs and what type of food they can properly digest based on their age.

There are a few distinctions that we'll go over in a bit, but the general rule is that young kittens should not eat adult food at least until after they're a full year old. In most cases, you may want to hold off for an additional few months to ensure that you don't do any harm to their growth.

But why is this the case with feline nutrition?

We'll go over the different parts of the kitten's life stage and their transition into an adult cat. 

We'll also go over some of the key essential nutrients and minerals that kittens need during their formative years so that they can properly grow and develop. Finally, we'll get into the different ingredients kitten's food should include so they can become as strong and as capable a cat as they possibly can.

Can Kittens Eat Adult Cat Food? 

While it might be tempting to let your youngster kitty munch on the same pet food as your adult cat, it's not the best idea. Kittens and adult cats have different nutritional requirements. Kittens grow at an astonishing pace during their first year of life, so they need a lot more energy and specific nutrients compared to adult cats. 

Remember, some cat breeds mature at a different rates. Larger breeds, like the Maine Coon, can take 18 months of age to 2 years to reach maturity. Always try and avoid "treating" them with any human food as well. 

So there are other variables to consider. 

Kitten Life Stage 

For all cats, there are three (sometimes four) stages of life that they should all go through. These include the Growth Stage, the Adult Stage, the Senior Stage, and the Geriatric Stage. 

While all of these four stages are important for a cat's overall health and wellness, in this overview, we're going to spend the majority of our time going over the initial "growth stage" as this is also the stage where your kitten will grow and develop from a helpless newborn into a fierce and independent cat.

All of these stages require their own appropriate levels of nutrition and high quality protein. 

Making errors at an early stage may lead to obesity or weight loss so it os best to get it correct from the off.

Growth Stage [Weeks 1-8]

The Growth stage starts from the moment a newborn kitten is born and ends approximately between the 10th to 12th month. During the initial four weeks, a kitten will go through the growth stage primarily getting all of their essential nutrients from their mother's milk or kitten formula. 

Once they are four weeks old, the weaning process begins, where the kitten is slowly introduced to more solid foods.

In the wild, during this time, small kittens are expected to spend some of their time nursing from their mother while also spending some of their time eating small amounts of solid foods. 

Domesticated kittens and cats can slowly be introduced to wet and canned cat food, only potentially being given dry food after an additional four weeks have gone by. 

This is because a kitten's teeth are likely to struggle a fair bit breaking down and crushing dry cat food, making it at best difficult to eat and, at worse, potentially a painful and dangerous process.

Growth Stage [Weeks 8-24]

By your kitten's second month (eighth week) of age, they should be entirely weaned from their mother's milk and only eat solid kitten food. The kitten food can be either entirely wet food or entirely dry at this point based on you and your kitten. For many pet owners, it is usually a combination of the two, which is also completely fine.

One thing to keep in mind is that, while kittens are able to eat either wet or dry kitten food, they should not eat any commercially processed cat food at this point. 

You'll want to make sure you're only giving them kitten food, avoiding any table scraps or pieces of meat you might otherwise be tempted to offer. We'll go over more in a bit, but this may have a potential impact on their digestion as well as not having the optimal amount of nutrients for them to finish developing.

Growth Stage [Weeks 24-52]

From the sixth month up until their first year, it's important that you are feeding them the recommended amount of kitten food. 

This is because, during this time, kittens go through their fastest rate of growth and development, able to increase their size and body weight by upwards of 40 or 50 times that of their newborn selves.

While a cat may "appear" to have reached adulthood by their sixth month, there is still a lot of internal development taking place with severe effects.

It's only after they've officially reached a year old that you should consider the switch and begin transitioning out to adult cat food as their body will have finished the bulk of its growth.

Read this next: Can Adult Cats Eat Kitten Food? (Or Is It Bad For Them?)

Essential Nutrients For Kitten Growth  

You may be wondering why it is that kitten food and cat food are so different from one another. Is the reason kittens can't eat cat food because of digestive or health reasons? While that's true to a minor extent, the main reason kittens should avoid eating cat food is more for what it lacks than what's included, and that all has to do with the various essential nutrients that a kitten needs to grow and develop compared to what an adult cat needs to maintain and survive.

Essential Nutrient #1. Protein 

Starting with arguably the most important of the three essentials, protein is one of the primary building blocks when it comes to growth and development. This is true for all living creatures - kittens included! In fact, because cats are carnivorous animals, they have levels of high-quality protein that they must maintain, which is only more emphasized when it comes to developing kittens.

Protein acts as the foundational forming of a kitten's skin, muscles, fur, and nails. It also plays a role in the development of their internal organs alongside their body's entire cellular growth and repair. It is also used as the basic building block for a cat's hormones, enzymes, and even its entire overall immune system. 

Simply put, protein is an essential part of just about every single aspect of a cat's (and kitten's) life.

But if all cat food has protein, why is it so important that they only eat kitten food?

Well, this is because of how the protein interacts with the body as well as how that relates to the way kitten food is produced compared to adult cat food. Protein is made up of essential and non-essential amino acids. These amino acids together are what allow the protein to have all of its positive effects. 

While non-essential amino acids are produced naturally in the body, essential amino acids can only be acquired when eating animal-derived foods. Since there isn't a single protein source that contains all amino acids, both cats and kittens must eat from a variety of sources in a balanced or properly supplemented way.

For adult cats, the amount of protein they require is around 25-26% on a dry matter (DM) basis. This means that, of the food they eat, once water is removed, it should be at least 26% protein. 

For kittens, however, this number jumps up to a minimum of 30%. Four or five percent may not seem like a lot on its head but bear in mind that these are minimum numbers, with kittens ideally getting upwards of 35-40% protein in their diet to ensure healthy growth. 

Adult cat food not only has less DM-based protein, but they are likely to have an insufficient amount of specific non-essential amino acids compared to kitten food, which will always have the minimum required for a kitten, often hitting the ideal and even maximum based on the brand.

Read this next: Can Cats Eat Rice? (Or Is Rice Bad For Cats?)

Essential Nutrient #2. Fat 

Outside of protein, cats also need a quality amount of fats in their diet. Not only should these fats be "healthy" fats like omega-3s (which have been shown to improve brain and eye function) but also normal fats in general. 

Because fat contains almost three times the amount of energy when compared to protein or carbohydrates, this is almost essential to keep up with a kitten's incredibly rapid growth.

Without an adequate amount of fat, they simply will not have the necessary energy to grow as large as they otherwise could. (Interestingly, this is also why you should not feed kitten food to adult cats as this can cause them to quickly gain weight and become obese if they aren't very active)

Fats and fatty acids are also vital factors as it pertains to a kitten's ability properly absorb certain fat-soluble vitamins, like vitamin A or arachidonic acid.

Essential Nutrient #3. Calories 

Lastly, while not necessarily a "nutrient", kittens also need a large number of calories. As mentioned with the fat-based reason, kittens need a lot of energy to grow. By feeding them kitten food with a high caloric density, you are ensuring they hit this growth while also not worrying about overfeeding them. If you feed them a low calorie cat food diet then they will lose weight and not develop well.

This is because cat food cans are much larger compared to kitten food cans. This is so that kittens can get just enough calories to nourish themselves while not being inundated with too many calories, causing them to grow overweight. This again is why your kitten shouldn't be eating cat food and vice versa. 

Importance Of Quality Ingredients 

In the question of quality ingredients, not only are these just as important as the nutrients themselves but actually potentially more important. This is because the nutrients involved must be easily accessible within the food. This can't happen if the ingredients aren't properly digestible or bioavailable.

As such, you want to always make sure you're picking up kitten and cat food that comes from animal sources and is easily recognizable without too many unidentifiable terms included. Simply put, you should only be getting kitten and cat food that prominently includes "chicken", "salmon", or "lamb". It should ideally not include things like "vegetable-based protein" or "cereal-based protein". 

Not only are these a lower quality of protein, but they are unlikely to have all of the essential amino acids while also being harder for their bodies to properly digest.

Whatever kitten foodBest Kitten Food (2022) – Wet and Dry Cat Foods For Kittens or cat food you get should also always have the sentence "Meets the nutritional requirements of kittens" included in some way as well as a reference to the American Association of Feed Control Officials (also known as the AAFCO).

Read this next: What Can Cats Not Eat? Protect Your Cat From Toxic Foods

Can Kittens Eat Adult Cat Food? The Verdict

When comparing a kitten to a human infant, there's a reason they're able to reach adulthood in a relative fraction of the time. It's in large part thanks to their diet and how it is in relation to their body.

For many, the idea of feeding your kitten cat food is considered the same as feeding a baby a steak or a cheeseburger. 

And while some aspects may lead to digestive issues, the truth is not that you're giving your kitten too much food, but rather the opposite. 

Kitten food is more calorie-dense, with more fat and protein compared to adult cat food, and a kitten that doesn't get it can run the risk of becoming severely malnourished.

It may seem like a while but stick with feeding your cat kitten food for the entire 12 months, even if they look like they're an adult around the halfway mark. 

Then, after they've officially had their first birthday, you can feed them whatever cat food you'd like. Just make sure it's using ingredients your cat can use so they stay big and strong!

If in doubt about your kitten's diet, or your adult cat's diet, always consult with your vet. A veterinarian's advice always helps and they can advise precisely on your kitten's nutritional needs. Some cats will have different nutritional needs, from others so it's always wise to consult with professionals.