Today on the canine version of Nutrition Nuggets, I introduced the idea that dietary sources of fat for dogs and cats shouldn’t be classified as being “good” or “bad” as they are in human medicine. As I was researching that concept, I ran across an article, written by veterinary nutritionist John Bauer that proposed the designation of “functional” or “facilitative” as being more appropriate for pets. Let’s examine that idea a little more closely.
According to Dr. Bauer:
A functional fat is usually, but not always, an essential fatty acid or derived from an essential fatty acid, participates in an important structural or functional cellular process, or is converted to an important derivative that regulates cell function. Functional fats in dogs and cats include the essential fatty acids LA [Linoleic acid] and ALA [α-Linolenic acid].
Functional fats provide for healthy skin and coat, promote health of the gastrointestinal tract and renal system, ensure adequate reproductive performance, control inflammation, and play an important role in neurologic development. Only small amounts of functional fats are required in the diet, and some can be synthesized from shorter precursors. However, providing some preformed long-chain forms of these fats appears to be conditionally essential, especially for certain life stages, such as growth and development, and processes, such as reproduction. This is especially the case for DHA [Docosahexaenoic acid], which is converted slowly and inefficiently from its shorter precursor, ALA, and for AA [Arachidonic acid] in cats in which conversion from LA is modest at best.
In other words, small amounts of functional fats, such as LA, ALA, DHA, and in cats AA, need to be supplied in the diet to play specific roles in particular body functions. Sources of functional fats are fish oils, purified algal oils, corn oil, soybean oil, sunflower oil, canola oil, and flaxseed oil although this last example appears to be poorly utilized in dogs and cats.
Facilitative fats play a more general role in the diet.
A facilitative fat improves palatability and increases the acceptable texture of foods, is a dense source of dietary calories and energy, promotes the absorption of fat-soluble vitamins … or has a combination of these characteristics. Included in the facilitative fats are dietary saturated fats such as palmitic and stearic; oleic, a monounsaturated fatty acid; and trans-fatty acids.
Facilitative fats can be found in relatively large amounts in diets of dogs and cats, and they do not typically pose a health risk [as they do in humans], except perhaps with respect to obese animals that are fed excessive amounts of high-fat diets that contain too many calories.
While we have to closely watch the different types of fat that we include in our own diets, the situation is a little simpler for dogs and cats due to their innate resistance to arthrosclerosis and the related risk of heart attack and stroke.
Dr. Jennifer Coates
Facilitative and functional fats in diets of cats and dogs. Bauer JE. J Am Vet Med Assoc. 2006 Sep 1;229(5):680-4.