International Omega-3 Learning and Education Consortium for Health and Medicine

A cat petfood formulated with ingredients such as fish, fish oil, and fish meal, which are sources of the long chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), will generally provide enough omega-3 fatty acids for your cat. Based on the National Research Council recommendations for the cat ¹ only sufficient amounts of the long chain omega-3 fatty acids EPA and DHA will meet the nutritional needs for the cat. Cat petfoods that are formulated with oils from vegetable sources that claim to have omega-3 fatty acids contain alpha-linolenic acid (ALA or 18:3n-3). The omega-3 fatty acid ALA is not converted to the biologically active forms EPA and DHA because the cat lacks sufficient enzyme activity (the delta 6 desaturase or Δ6 desaturase) to make this conversion as shown below. The omega-3 fatty acid that the cat must have in petfood includes EPA and DHA. Therefore, ALA, as an omega-3 fatty acid in general, has little value for the cat ¹.

It is somewhat difficult to know exactly how much omega-3 fatty acids are present in cat petfood products; however, this does not seem to be a major hurdle in providing the cat with an adequate amount of omega-3 fatty acids. Omega-3 fatty acids are components of dietary fat found in fish and fish oil and once ingested, they are readily digested and absorbed like other dietary fats. The omega-3 fatty acids are used like other fatty acids in the cat and become components of cell membranes. Therefore, the long chain omega-3 fatty acids are well tolerated and have a wide margin of safety when used in cat petfoods. According to the National Research Council, omega-3 requirements for cats are fairly moderate, which means that cat petfoods enriched with fish or fish products should have adequate amounts of the long chain omega-3 fatty acids EPA and DHA.

According to the Nutrient Requirements of Dogs and Cats of the National Research Council ², the current dietary recommendations for the amount of essential fatty acids are based on the developmental stages of dogs and cats. Until recently, there were no official recommendations for ALA and DHA intakes for cats, but now these estimates are presumably adequate for growing kittens: 0.02 - 0.03% of dry matter (DM) (i.e., 200 to 300 mg/kg dry diet) for ALA and 0.01 - 0.02% DM for DHA. There are no data indicating that ALA and long chain omega-3 fatty acids are required for adult cat maintenance; therefore, the estimated adequate intake (AI) is set at 0.01% of DM for (EPA + DHA) at the moment. Small amounts of DHA (0.01 - 0.03% DM) are presumably adequate in providing the benefits of these fatty acids.

On the label of some petfood packages, there is an analyzed quantity that claims to contain a certain amount of omega-3 fatty acids. The quality of the omega-3 fatty acids is largely dependent on the sources of the ingredients listed on that petfood label. Therefore, special attention should be paid to the list of ingredients on the petfood label when determining the quality of that petfood product.

As previously stated, the long chain omega-3 fatty acids (EPA and DHA) in petfoods come from ingredients such as fish oil, fish meal, and other fish products. The essential omega-3 fatty acid, ALA, is from ingredients of vegetable sources such as soybean oil, canola oil, soy flour, flaxseed, flax meal, soybean meal, canola meal, and others. For cats, however, do not pay too much attention to the ALA content (or sources) in the cat petfood.

One should keep in mind that the total omega-3 fatty acid values or the specific omega-3 fatty acids are not mandatory information placed on the petfood label. For this reason, the consumer will see a footnote that says "Not recognized as an essential nutrient by the AAFCO (Association of American Feed Control Officials) Cat Food Nutrient Profiles".

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