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Do Immune Boosting Supplements for Cats Work? Here’s What Science Says

Veterinarian gives a pill to a cat

There are many cats that may benefit from a bit of a boost in their immune system. Older felines are often at risk of severe complications from superficial infections, especially if they have underlying conditions. Some health conditions can affect a cat’s immune system. In this case, you may want to give your cat a supplement to boost their immune system as much as possible.

There are countless supplements on the market that claim to support your cat’s immune system. However, what does the science say about their effectiveness, and which ones work the best? In this article, we’ll take a look at the science behind immune-boosting supplements for cats and help you determine if one may be suitable for your feline.divider-cat

Are Cat Vitamins and Supplements Necessary?

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Your cat’s body is designed to function in a specific way with specific vitamins and nutrients. If your cat’s body does not have enough of these nutrients, it may not function effectively. For instance, if your cat’s immune system doesn’t have everything it needs to function, it may not work as well as it would otherwise.

However, adding more nutrients than your feline needs isn’t going to boost their immune system further. They can only use so many nutrients. Adding extra doesn’t do anything besides adding more strain to the body to filter them out.

Of course, some cats may be more at risk for vitamin deficiencies than others. Some may have absorption problems that may directly affect their ability to use the vitamins they consume. These cats may be deficient even if they are eating a complete diet.

Often, the “minimum” amount of a vitamin isn’t necessarily enough for all cats. Your feline may benefit from more of a particular vitamin over the minimum. This is especially true for kittens and nursing cats, who are often using more of specific vitamins than adult cats. Just like pregnant humans often need a supplement, pregnant cats need extra nutrients as well.

Supplements vs. Nutraceuticals

Before we move forward, it is essential to understand the difference between a supplement and a nutraceutical. A supplement is simply designed to fill a nutritional deficiency. These often include many different vitamins and minerals. Things like fish oil pills and probiotics would also fit into this category.

A nutraceutical is a supplement or natural remedy that is more of a diet additive than a supplement. It isn’t aiming to fill any particular gap in nutrition. Instead, it contains high levels of specific ingredients that are thought (or proven) to be helpful in certain situations. Most immune supplements fall into this category. Therefore, you can’t simply look at the nutritional information of the supplement can check that it includes 100% of your cat’s daily value. The dosage for nutraceuticals is often far more than the minimum recommended amount.

Nutraceuticals may act like a drug and produce pharmaceutical-grade benefits. In some cases, vets may actually recommend this sort of additive instead of prescription medication. However, they are not technically a drug and do not require a prescription. For instance, glucosamine is often recommended as a joint supplement, as it has been found to lessen the effects of joint problems.

Of course, not all nutraceuticals work effectively. Some are more science fiction than science fact.divider-food2

Do Immune Supplements for Cats Work?

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The immune system requires some particular nutrients to work properly. If given more of these nutrients than the minimum daily recommendation, the immune system may work better. After all, remember that the daily values are minimums. They’re what your cat needs to work “okay.” However, more is sometimes a good thing.

There haven’t actually been that many studies done on immune supplements from cats. One of the very few that we have was published in 2013. This study only included 43 cats. These cats were split into different groups and supplemented with different things. The immune system was then measured based on the lymphocyte proliferative response, which is basically how strongly the immune system responds to a germ.

The supplements arginine, nucleotide, and salmon oil all showed significantly more immune response than the control group. The study concluded that supplementation might help the immune system of healthy cats respond better to infections and diseases.

Therefore, it does seem like these supplements work. While more studies are necessary, the current information looks very promising. Of course, we recommend choosing one or more of the supplements used in the study when you’re trying to boost your cat’s immune system.

There are other supplements that may be helpful that weren’t directly studied in this study. For instance, probiotics are often thought to affect the immune system. One paper looked at several studies involving probiotics and cats. Statistically speaking, cats seemed to be affected by certain infections for fewer days when they were given a probiotic supplement. There are very few side effects to probiotics as well, so this is usually considered a safe option for most felines. ‘

L-lysine has been shown to have minimal effects on the immune system, though they are short-term. If used to improve your cat’s immune system, this supplement needs to be given regularly.

What is the Best Immune Supplement for Cats?

This will vary from cat to cat. We recommend taking a look at your cat’s regular food before choosing a supplement for them. If your cat’s food contains a high amount of fish oil, then they likely don’t need an extra fish oil supplement. Some cat foods already contain probiotics, which may limit the need for even more probiotics.

In general, there are quite a few high-quality immune supplements for cats on the market.

Not all of these will be suitable for every cat, depending on their diets and needs:

What Immune Supplements Don’t Work?

There are many supplements on the market that aim to support your cat’s immune system. However, there isn’t a lot of science backing many of them. For instance, many include mushroom extracts, though we have no evidence that these help your feline’s immune system. No scientific information is available on how these mushrooms may affect your cat’s body, potential side effects, and medications they may interact with.

For this reason, we do not recommend giving your feline supplements that have not been studied extensively.

happy cat
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Some immune supplements for cats do work. However, not all of them are made equal. Science has discovered that certain nutrients have an immune-boosting effect. Supplements that contain these ingredients do tend to work efficiently. Of course, the exact effect varies from cat to cat.

There are several immune supplements on the market that contain ingredients that haven’t been tested. No one knows if these supplements work or if they have any significant side effects. For this reason, we can only recommend supplements with current science behind them.

Featured image credit: Piskova Photo, Shutterstock

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