Why Antioxidants Matter in Your Cat’s Diet

Kirsten McCarthy / Cats.com

Antioxidants are nutrients that prevent or slow damage caused to your cat’s cells by free radicals. Antioxidants are vital to your cat’s immune system and are thought to reduce their risk of diseases like diabetes mellitus, cancer, and cognitive decline. Examples used in cats include vitamins E and C, selenium, and beta-carotene.

So, how do you ensure your cat is getting enough? Read on for everything you need to know about antioxidants in cats, from how they work to what foods contain them.

What are Antioxidants?

Your body produces ‘free radicals’ during everyday metabolic processes. Whilst free radicals have some useful functions, too many result in cell damage or death. Free radicals are linked to multiple diseases in cats, as well as premature aging. As well as being produced naturally, things like pollution, cigarette smoke, infections, and exposure to toxins can all increase free radicals in your cat’s body.

Antioxidants work by neutralizing free radicals, protecting against their harmful effects.

Your cat’s body must maintain the right balance of free radicals and antioxidants to prevent damage. When free radicals overpower antioxidants, it leads to ‘oxidative stress’, which can be detrimental to their health. This is why ensuring your cat has enough antioxidants in their diet is important.

By fighting free radicals, antioxidants slow or prevent cell death and damage, protecting your cat’s body from oxidative stress. This reduces the effects of premature aging and protects your cat against illnesses linked to cell damage, including cancer.

What are the Benefits of Antioxidants in Cats?

Antioxidants are shown to boost your cat’s immune system as well as reduce their risk of many health problems. Kirsten McCarthy / Cats.com

Antioxidants reduce your cat’s risk of many health conditions, such as:

• Heart disease
• Diabetes
• Kidney disease
• Inflammatory conditions, including arthritis and inflammatory bowel disease (IBD)
• Cancer
• Premature aging
• Cognitive decline (dementia)

Antioxidants and Your Cat’s Immune System

We also know that antioxidants boost your cat’s immune system, protecting them from a whole range of possible illnesses.

One recent study on the effect of dietary antioxidants on free radical damage in dogs and cats concluded that “cats fed an antioxidant blend inclusive of vitamin E, vitamin C, and β-carotene have improved immune health as observed through reduced signs of oxidation and decreased cellular breakdown.”

Comprehensive research on Feline immunocompetence, ageing, and the role of antioxidants found a greater immune response to vaccination in cats fed a diet supplemented with antioxidants, compared to cats with no antioxidant supplement.

They also found that the immune cells themselves were stronger and less fragile in cats fed a diet rich in antioxidants compared to those on a standard diet. This could make them better at fighting off disease and infection.

Sources of Antioxidants for Cats

While antioxidants are found in many plant-based foods, meat-based sources are more appropriate for cats, such as fish, shellfish, lean meat, and poultry. Kate Barrington / Cats.com

Strictly speaking, antioxidants aren’t specific ingredients, but substances that have antioxidant properties, usually among other benefits. Examples of substances known to have antioxidant effects in cats include:

• Vitamin E (may be listed as tocopherol)
• Vitamin C (may be listed as ascorbic acid)
• Carotenoids, such as beta-carotene and lutein
• Selenium
• Taurine

Antioxidants can be found in plant-based and meat-based ingredients. While your cat may tolerate small amounts of plant-based options (such as sweet potato, blueberries, pumpkin, seaweed or leafy greens), meat, fish, and eggs offer a more carnivore-appropriate choice to boost their levels of antioxidants.

Read our top 9 Disease-Fighting Antioxidant Foods for Cats to learn more about the best antioxidant-rich foods for cats.

How to Give Antioxidants To Your Cat

The safest way to ensure your cat is getting the optimal amount of antioxidants is to feed them a balanced and complete diet, appropriate to their life stage and health. Kirsten McCarthy / Cats.com

Now you know how important antioxidants are, you’ll want to ensure your cat is getting enough. There are three main ways to ensure this: checking your cat’s diet meets AAFCO standards, choosing a diet with added antioxidants, or giving your cat an additional supplement.

Antioxidants in Regular Cat Food

The good news is that all diets that are complete and balanced, as established by the Association of American Feed Control Officials (AAFCO), must contain adequate amounts of essential micronutrients. This includes some with antioxidant properties, such as vitamin E, selenium, and taurine.

So, if your cat is fed a complete and balanced diet appropriate for their life stage, you can rest assured they will already be receiving a healthy dose of antioxidants. To check if your cat’s food meets AAFCO standards, look for the “AAFCO statement” on the packaging.

Specialized Diets Rich in Antioxidants

While all pet foods approved by the AAFCO will meet minimum nutritional requirements, some diets go above and beyond.

Recognizing the benefits of antioxidants, many specialized diets contain added antioxidants. These include diets designed to manage health conditions, such as heart disease and gastrointestinal issues.

With the increased risk of oxidative damage in older pets, high-quality diets designed for senior cats or those with cognitive decline (dementia) should also contain high levels of antioxidants.

Antioxidant Supplements

If you want to increase your cat’s intake of antioxidants, you can also consider using a supplement. These come in capsules, liquids, powder, chews, and tablets.

Most supplements for cats contain a variety of vitamins, minerals, and other ingredients, rather than just ingredients with antioxidant properties. Unfortunately, in most countries, supplements are not as regulated as other medications. This means they can be sold without manufacturers having to prove that the product contains what it claims to, is effective, or is safe.

What Happens If Your Cat Doesn’t Get Enough Antioxidants?

Your cat needs enough antioxidants to combat the levels of harmful free radicals in their body. We know that the activity of natural antioxidants reduces as your cat ages, making them more susceptible to oxidative damage and illness. So, antioxidants are even more important for our senior cats.

Diets that do not contain enough antioxidants, especially vitamin E, taurine, and selenium, can lead to poor immune health and an increased susceptibility to aging, cancer, and disease.

The safest way to ensure your cat receives the right level of antioxidants is to feed them a commercial diet that is complete and balanced. Choosing a diet specific for their life stage, such as a senior diet, will also take into account the increased need for antioxidants in older cats.

What are the Risks of Antioxidants in Cats?

AAFCO-approved diets with antioxidants are tested for safety and nutrition—but every cat is different. Kirsten McCarthy / Cats.com

Commercial diets containing antioxidants that are approved by the AAFCO (or the pet food safety agency in your country) are considered safe. They are tested to ensure that they contain the levels of nutrients they claim, and these levels must be within safe ranges. Although, of course, not all diets will agree with every individual cat.

The main risk of antioxidants in cats comes with supplementing your cat’s existing complete diet, as it is difficult to know if they could be getting too much. As mentioned above, in most countries, supplements are not well-regulated. This means that companies are generally not required to prove supplements contain what they claim to, or prove that they are safe.

Antioxidant Toxicity in Cats

Like most things in life, you can get too much of a good thing. While antioxidants can certainly boost your cat’s overall health and well-being, high levels can be dangerous. Antioxidant toxicity is rare in cats, but can be seen in cats fed excessive supplements or diets that are not appropriately balanced, such as home-cooked diets.

For example, high levels of vitamin A (usually seen in cats fed a diet rich in liver or cod liver oil) can cause vomiting, anorexia, muscle pain, and neurological symptoms, as well as serious changes to your cat’s bones. Excess vitamin E has been linked to bleeding issues in cats, while selenium toxicity in animals has been shown to cause damage to the muscle, heart, liver, spleen, and kidneys.

Side Effects of Antioxidants in Cats

Even at the correct levels, all supplements can cause side effects, such as vomiting and diarrhea. They also have the potential to interact with medication, including herbal remedies. So, always consult your veterinarian before starting your cat on a supplement.