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What To Do If Your Cat Will Only Eat Tuna!

Although there is a pretty strong stereotype of cats that will only eat tuna or other types of fish in children’s cartoons, this is a reality for some cats and it is not a healthy diet that is far from being nutritionally complete.

Depending on the type of tuna you feed your cat, it may actually post a health risk when eaten in large quantities too.

We have noticed a number of people reaching out asking about why their pet cat will only eat tuna recently so we have decided to publish this article going over topic.

It is important that you try to diversify your pet cat’s diet as fast as possible as a diet of nothing but tuna is not suitable for your cat and it will quickly develop problems.

In many cases, the lethargy, poor coat, and internal issues may have already started.

Due to this, we really hope that this article will be able to help as many of our readers as possible but in many cases, you really should be getting your pet cat to a vet as soon as possible if it is only eating tuna.

A quick check up and some bloodwork should be able to give you an idea of any potential long term problems as well as the various supplements or treatments that may be able to help your cat.

Is It Okay For Cats To Only Eat Tuna?

No, it is not okay for cats to only eat tuna.

Tuna does not provide all of the nutrients that a cat needs to stay healthy and will eventually lead to health problems if your cat continues to eat nothing but tuna.

A diet of only tuna can cause a number of problems for your cat including but not limited to:

  • Lethargy
  • A Poor Coat
  • Internal Issues
  • Nutritional Deficiencies

These are just a few of the problems that can be caused by a diet of only tuna and in many cases, these problems may have already started if your cat has been eating nothing but tuna for a while.

In addition to the health problems that can be caused by a diet of only tuna, it is also important to note that tuna can actually be dangerous for cats in some cases.

Depending on the type of tuna, it may contain high levels of mercury which can be poisonous for your cat too.

Is It Normal For Cats To Only Eat Tuna?

It is not normal for a cat to only eat tuna and this behavior in a cat is almost always due to the habit being built up over time of their owner feeding them nothing but tuna.

This may be out of convenience, due to your cat liking tuna initially or due to your cat having problems with its jaw making it difficult to eat other food sources.

That said though, it is definitely not normal or natural for a cat to eat nothing but tuna.

Although a cat is an obligate carnivore that requires a meat based diet, the majority of tuna products are far too high in protein for a cat and lack the fats it needs for energy.

The macronutrient balance in the diet of a cat is very important but due to most people just feeding their pet cat a premade commercial cat food, there is usually no need to worry about it.

The unsuitable protein to fat ratio found in tuna fish can quickly cause problems in your cat and you should try to add additional food sources as soon as possible.

Why Does My Cat Only Eat Tuna?

There are a few reasons as to why your cat only eats tuna and it may be due to a combination of these factors.

Your Cat Prefers Tuna

The first and most common reason is that your cat has become used to eating tuna and it simply prefers the taste or smell of tuna over other food sources.

This is usually due to their owner feeding them tuna out of convenience or because they think their cat likes tuna more than other food sources.

If this is the case, you may be able to slowly transition your cat onto a new diet by mixing in new food sources with the tuna until your cat becomes used to eating them.

Your Cat Is Used To Eating Tuna

Another common reason as to why your cat only eats tuna is that they are simply used to eating it.

This usually happens when a pet owner has been feeding their cat tuna for a long period of time and they have become accustomed to the taste and smell of it.

If this is the case, you will need to slowly transition your cat onto a new diet as well by mixing in new food sources with the tuna until they become used to eating them.

Your Cat Has A Health Problem

Another potential reason as to why your cat only eats tuna is that they may have a health problem that is causing them to lose their appetite for other food sources.

If this is the case, you will need to take your cat to the vet to have them diagnosed and treated.

Your Cat Is Picky

Lastly, it is also possible that your cat is simply picky and does not like the taste or smell of other food sources.

If this is the case, you may be able to find a new diet that your cat will eat by trial and error or by consulting with a veterinarian.

How Do I Transition My Cat Onto A New Diet?

If you have decided that you want to transition your cat onto a new diet, there are a few things you will need to do in order to make sure the process goes smoothly.

Use A Gradual Process

The first thing you will need to do is slowly introduce new foods into your cat’s diet while gradually decreasing the amount of tuna you are feeding them.

You can do this by mixing the new food with the tuna or by feeding them small amounts of the new food on its own.

It is important to go slowly though as it may take your cat a while to get used to the new tastes and smells.

Perfect The Ratio

The default ratio for a food switch is usually steps of 25% over the course of a couple of days with many cats being able to switch over without issue at this rate.

You can use the following ratios as an example when trying to get your cat to eat foods other than tuna:-

  • 100% Tuna.
  • 75% Tuna – 25% New Food.
  • 50% Tuna – 50% New Food.
  • 25% Tuna – 75% New Food.
  • 100% New Food.

Although this may sound basic, it is a very popular ratio that is used for both cats and dogs while also having a high success rate.

That said, in some cases, you may have to tweak the ratio, especially for a stubborn cat or a cat that has been on a tuna based diet for a long time.

This may mean that you may need to use the 10% ratio and change your cat over at changes of 10% every two to three days.

Play around with the actual ratio for your cat and see what it seems to prefer.

Consult With A Veterinarian

If you are having difficulty transitioning your cat onto a new diet, you may want to consult with a veterinarian.

They will be able to help you figure out what is causing your cat to only eat tuna and they can also recommend a new diet for your cat that they are more likely to eat.