Omega Fatty Acids for Cats: Omega-3 vs Omega-6, Simply Explained

Omega fatty acids for cats are fats the body needs for skin, coat, eyes and normal growth. They come in two families, omega-6 and omega-3. Both matter, but they do different jobs.

Still, cats are a special case. Their bodies cannot make some of these fats the way dogs or people can. So the type of fat in the bowl matters as much as the amount.

This guide explains omega fatty acids for cats in plain words. We cover each family, the best sources, signs of a gap and how to stay safe.

The two families of omega fatty acids for cats

First, fatty acids get their names from their shape. Omega-6 and omega-3 are both polyunsaturated fats, but their chemistry differs. As a result, the body uses them in different ways.

• Omega-6 fats: linoleic acid (LA) and arachidonic acid (AA).
• Omega-3 fats: alpha-linolenic acid (ALA), EPA and DHA.
• Omega-9 fats: such as oleic acid, which most guides do not list as essential for cats.

A vet nutritionist's review in Today's Veterinary Practice sums it up well. Linoleic acid is essential for both dogs and cats, while arachidonic acid is essential only for cats.

Omega-6: the omega fatty acids for cats you hear less about

Omega-6 fats get less press, but cats cannot do without these omega fatty acids for cats. The Merck Veterinary Manual states that all mammals, including cats, need linoleic acid in the diet.

Cats also need arachidonic acid. Merck notes this fat is absent in vegetable oils and fats. It also says that, unlike dogs, cats cannot readily convert linoleic acid to arachidonic acid.

Why? Cats lack enough of an enzyme called delta-6 desaturase. A classic paper in Nature first showed the inability of the cat to desaturate essential fatty acids. So arachidonic acid must come from animal tissue, such as meat and fat.

This is one reason cats are true meat eaters. Good omega fatty acids for cats start with animal protein and fat.

Omega-3: ALA, EPA and DHA

Next, omega-3 fats are the ones on most supplement labels. The Ontario Veterinary College explains that ALA is a short-chain omega-3, while EPA and DHA are long-chain omega-3s.

For cats, the long-chain pair matters most, because conversion is poor. WikiVet notes that cats are unlikely to make much EPA from ALA, given their low delta-6 desaturase activity. The 2016 review adds that poor ALA conversion is why the NRC lists EPA and DHA needs for cats.

DHA is key for young cats. A study found that only diets with DHA built high DHA levels in the retina and brain, and that young felines have a low ability to make DHA. For more on this pair, see our guide to EPA and DHA for cats.

Omega fatty acids for cats: side-by-side comparison

This table puts the main omega fatty acids for cats side by side. Use it as a quick map, not as a dosing guide.

The pattern is clear. Cats rely on ready-made fats more than many animals do. That is why omega fatty acids for cats should come mostly from animal and marine sources.

Food sources of omega fatty acids for cats

The NIH Office of Dietary Supplements notes that DHA and EPA are present in fish, fish oils and krill oils. In contrast, ALA comes from plant oils such as flaxseed, soybean and canola.

• Meat and animal fat: linoleic acid and arachidonic acid.
• Fish and fish oil: EPA and DHA.
• Algal oil: EPA and DHA from algae.
• Plant oils: linoleic acid and ALA, but no arachidonic acid, EPA or DHA.

Overall, a complete and balanced cat food aims to cover these needs. If you want whole-food ideas for omega-3s, read our guide to omega 3 foods for cats.

Is there an ideal omega-6 to omega-3 ratio

Many labels talk about ratios. However, there is no single agreed ratio for every cat. WikiVet notes that proposed ratios of linoleic acid to ALA for skin and coat range widely, from 2.6:1 to 26:1.

That range is too wide to guide a home plan. So vets usually look at the total EPA and DHA a cat gets instead. A vet nutrition article on fish oil dosing advises adding up the EPA and DHA from both food and supplements.

In short, do not chase a ratio on a label. Instead, check that the food is complete and balanced, then ask your vet whether extra omega-3 makes sense.

Signs your cat may be low on omega fatty acids for cats

In fact, a true lack of omega fatty acids for cats is rare on complete food. Merck calls essential fatty acid deficiency extremely rare in cats and dogs fed complete and balanced diets. A review on diet and skin disease in dogs and cats agrees that most deficiencies are now uncommon.

Still, the same review notes that omega-6 deficiency can arise in certain cases. These include poorly made homemade diets or foods that went rancid.

• A dry, scaly or dull coat.
• More flakes or dandruff than usual.
• Slow hair regrowth.
• Low energy.
• In breeding cats, problems with reproduction.

But these signs are not specific. Fleas, mites, allergies and other health issues cause the same changes more often. So see your vet first. Our guide to cat dandruff covers the other causes.

How to check omega fatty acids for cats at home

1. Check that the food says "complete and balanced" for your cat's life stage.
2. Look at the coat and skin in good light, and note flakes or dull patches.
3. Book a vet check to rule out fleas, mites, allergies and illness.
4. Agree on any omega-3 plan, including the EPA and DHA amount.
5. Recheck the coat after several weeks, since skin and hair take time to change.

This simple routine keeps omega fatty acids for cats in the right place. They support a good diet and vet care. They do not replace either one.

Safety tips for omega fatty acids for cats

With omega fatty acids for cats, more fat is not always better. A review of possible side effects of omega-3s in dogs and cats lists changes in platelet function, stomach upset, slower wound healing, fat oxidation and weight gain.

• Watch calories: oils are dense in energy.
• Keep oils fresh: rancid fat can harm more than help.
• Mind vitamin E: the Merck guide to muscle disorders links yellow fat disease to too many unsaturated fats with too little vitamin E.
• Tell your vet: this matters before surgery or with other medicines.

Supplements can also push some nutrients too high. The AAFCO supplement guide says healthy cats on a complete diet generally do not need supplements. It also urges owners to talk to the vet first.

Life stage needs

Among omega fatty acids for cats, DHA matters most for kittens, since it supports normal eye and brain growth. That is why many kitten foods add it, often from fish oil or algae.

Adult cats usually meet their needs from complete food, so extra oil is often not needed. Senior cats may move to a vet diet, and some of these add more EPA and DHA. If your cat eats a prescription food, do not add oils without asking.

Our guide to omega-3 for cats covers the main omega-3 questions. For a fish oil deep dive, read fish oil for cats.

Reading a label for omega fatty acids for cats

Pet food labels show less than you might think. The AAFCO guide notes that the guaranteed analysis typically lists only crude protein, crude fat, crude fiber and moisture. So "crude fat" tells you how much fat is in the food, but not which fats.

Because of this, look for other clues. For example, check the ingredient list for named animal fats, fish or fish oil. Also look for the words "complete and balanced" with a life stage, such as adult or growth.

• Named animal fat: such as chicken fat, which supplies omega-6 fats.
• Fish or fish oil: a sign of added EPA and DHA.
• Algal oil: another source of DHA, often in kitten foods.
• Life stage claim: shows the food aims to meet all known needs.

If you still have questions, call the pet food maker. Many brands will share the omega fatty acids for cats in each recipe, including EPA and DHA, when you ask.

Omega fatty acids for cats on homemade or raw diets

Homemade diets carry the most risk. That is because each recipe must cover linoleic acid, arachidonic acid and omega-3s, plus vitamin E to protect those fats. Even a small gap can add up over months.

For example, a recipe based on lean meat and plant oil may miss arachidonic acid. In contrast, a recipe heavy in fish may bring too many unsaturated fats with too little vitamin E. Both are real problems for omega fatty acids for cats.

So if you cook for your cat, ask a board-certified vet nutritionist to build or check the recipe. Also, store fats and oils cold and use them before they go stale.

How omega fatty acids for cats support skin and coat

Skin and coat show fat status first. Merck lists a dry, scaly, lusterless coat as one sign of essential fatty acid deficiency. That is why owners often link a dull coat with fats.

However, the link runs one way. Low fats can cause a poor coat, but a poor coat rarely means low fats in a cat on complete food. Instead, fleas, mites, allergies, ringworm and grooming problems are more common causes.

Even so, omega fatty acids for cats remain part of a healthy coat routine. A complete food, regular brushing and a vet check together give the best picture.

5 common mistakes

• Using only plant oil: it lacks arachidonic acid, EPA and DHA.
• Chasing a ratio: total EPA and DHA matters more.
• Adding oil to a complete diet without a plan: this can add calories and upset the gut.
• Ignoring freshness: old oil oxidizes.
• Treating flaky skin with oil alone: fleas, mites and allergies are more common causes.

Avoid these and omega fatty acids for cats stay simple. Feed a complete food, add only what your vet supports and keep products fresh.

When to ask your vet about omega fatty acids for cats

• Your cat has new flakes, a dull coat or itchy skin.
• You feed a homemade or raw diet.
• Your cat has a health condition or takes daily medicine.
• You plan to add fish oil, algal oil or any other fat.
• Surgery or dental work is coming up.

After that, your vet can review the full diet. The WSAVA Global Nutrition Guidelines encourage a nutrition check at every visit, so this is a normal question to ask.

Related guides: EPA and DHA for cats · Omega-3 for cats · Fish oil for cats · Cat dandruff · Omega 6 for cats · Dry cat fur

Key Terms

• Essential fatty acid: a fat the body cannot make in enough amounts, so it must come from food.
• Linoleic acid (LA): an omega-6 fat that cats need in the diet.
• Arachidonic acid (AA): an omega-6 fat that cats need from animal sources.
• ALA: a short-chain omega-3 from plant oils.
• EPA and DHA: long-chain omega-3 fats found mainly in fish and marine oils.
• Delta-6 desaturase: an enzyme that helps convert fats; cats have low activity.

This article is for general education and is not veterinary advice. These statements have not been evaluated by the Food and Drug Administration. Kittysum products are not intended to diagnose, treat, cure or prevent any disease.