The world of cat supplements has grown a lot in recent years. What used to be a small shelf with a few options has turned into a full-blown category, and if you’ve found yourself squinting at ingredient lists, wondering what half of it means, you’re in good company.
Cats are unique when it comes to nutrition. As obligate carnivores, their bodies are wired differently than dogs or humans, and that means not every ingredient that’s popular in the broader pet supplement space is relevant or even safe for them. Knowing what’s actually in the products you’re looking at is a solid first step.
Here’s a rundown of some natural ingredients you’re likely to come across in cat supplements, what they are, and what’s worth knowing about each one.
Fish Oil
Fish oil is one of the most established natural supplements for cats. It’s a source of omega-3 fatty acids, specifically EPA and DHA, and it’s been used in the pet world for a long time.
For cats, fish oil is usually available as a liquid that you pump or drizzle over food. Most cats seem to find the taste appealing (go figure), which makes it one of the easier supplements to administer. Some cat foods already include fish oil in their formulation, so it’s worth checking what’s already in your cat’s diet before adding more.
Quality-wise, the same rules apply as they do for any fish-based product: look for wild-caught sourcing, check that it’s been tested for heavy metals and contaminants, and store it properly after opening. Fish oil can oxidize and go rancid, so keeping it refrigerated is usually a good move.
Probiotics
Probiotics have become a common addition to the cat supplement lineup. They’re live beneficial bacteria that support the digestive system, and you’ll find them in powders, chews, and some cat food formulations.
The strains used in cat-specific probiotics aren’t always the same as those used for dogs or humans. Products designed specifically for cats will use strains that are more relevant to a feline digestive system.
One thing to keep in mind about probiotics is that they’re live organisms, so how they’re stored is very important. Heat, moisture, and time can all reduce their viability. Look for products with clear storage instructions and an expiration date, and favor brands that can tell you how many colony-forming units (CFUs) are guaranteed at the time of use, not just at the time of manufacture.
L-Lysine
L-Lysine is an amino acid that shows up in a lot of cat-specific supplements. It’s one of those ingredients that’s far more common in the cat world than the dog world, which makes it worth knowing about if you’re a cat owner.
You’ll find it in chews, powders, and gels, and it’s often marketed toward cats of all ages. It’s been a fixture in the cat supplement space for years, making it one of the more established ingredients on this list.
If you’re considering an L-Lysine product, look for one that lists the amount per serving clearly. As with any supplement, the dose matters, and products that are vague about how much they contain aren’t giving you enough to go on.
CBD
CBD has made its way into the cat supplement space in a big way over the last few years. If you’re not familiar, it stands for cannabidiol, a naturally occurring compound from the hemp plant. It’s not THC, so there’s no intoxicating effect, which tends to be the first concern cat owners raise.
One of the more common formats you’ll see is CBD chews for cats, which have become popular partly because they’re easier to administer than oils or tinctures (anyone who’s tried to give a cat a dropper full of anything knows the struggle). That said, oils and topicals exist, too, if your cat isn’t a chew fan.
The CBD category for cats is still relatively young compared to something like fish oil, so product quality varies more than you might assume. Brands that are transparent about where their hemp is sourced, how their products are processed, and what their third-party lab results show tend to be the ones worth paying attention to. If that information isn’t easy to find, you’re better off finding another brand that does. And if you’re looking for greater assurance, seek out pet CBD companies that conduct clinical studies and peer-reviewed research to validate the safety and efficacy of their particular products.
Salmon Oil
Salmon oil is fish oil’s more specific cousin, and it’s become especially popular among cat owners who are focused on coat health. It’s rich in omega-3 and omega-6 fatty acids and tends to be a hit with cats taste-wise.
The liquid form with a pump is the most common format for cats, and it’s easy to add to wet food at mealtime. Some owners also find it helpful during seasonal changes when their cat’s coat or skin seems to need a little extra support.
The same sourcing and storage guidelines apply here as with general fish oil: wild-caught is preferred, third-party testing for contaminants is important, and refrigeration after opening helps prevent the oil from going rancid.
Slippery Elm
Slippery elm is an herb that’s been used in traditional practices for a very long time, and it’s made its way into a number of cat supplements. It comes from the inner bark of the slippery elm tree and is typically available as a powder or in capsule form.
In the cat world, you’ll sometimes see it included in digestive-focused supplements or as a standalone ingredient that owners mix into food. It has a mucilaginous texture when mixed with water, which some cats tolerate better than others.
If you’re exploring slippery elm for your cat, keep in mind that it can potentially interact with the absorption of medications. Giving it at a time separate from any prescriptions your cat takes is generally recommended, but your vet can give you specific guidance on timing.
Cranberry
Cranberry has been a popular natural ingredient in the human supplement world for years, and it’s carved out a niche in the animal space as well. You’ll find cranberry extract in a number of cat-specific supplements, often in chew or powder form. It’s one of those ingredients where the extract form is more common than the whole fruit, since most cats aren’t going to eat an actual cranberry (and the sugar content in cranberry juice makes that a non-starter). The concentrated extract is what you’ll see in supplement formulations.
As with any natural compounds or ingredients, check the amount per serving and look for products that use a standardized extract so you know what you’re getting is consistent from dose to dose.
Brewer’s Yeast
Brewer’s yeast is a natural source of B vitamins, and it’s been used in pet supplements for decades. It’s one of the more old-school ingredients on this list. In fact, your parents or grandparents might have given it to their pets, too.
In cat supplements, you’ll see it as a powder, in tablet form, or as an ingredient in multi-purpose blends. Some cats seem to like the taste, which is a nice bonus given how finicky cats can be about anything new in their food.
One thing to note: Brewer’s yeast is not the same as nutritional yeast or baking yeast. They’re different products with different nutritional profiles, so make sure what you’re buying is actually brewer’s yeast if that’s the ingredient you’re looking for.
A Final Note on Cats and Supplements
Cats are more sensitive than dogs to a lot of things, from ingredients and palatability to even the format a supplement comes in. What works well for a dog (or a human) isn’t automatically safe or appropriate for a cat, which is why cat-specific formulations matter more here than in almost any other category.
Another thing to note is that one of these ingredients is a requirement for a cat’s overall well-being. Your cat can be perfectly happy and healthy without any of them. But if you’re curious about what’s out there, understanding what each ingredient actually is gives you a better starting point than just trusting the packaging.
And when in doubt, your vet is always the best person to ask. They know your cat’s history, any medications they’re on, and whether a particular ingredient makes sense for your specific situation. A quick conversation can save you a lot of guesswork.