What are fatty acids?

Fatty acids are an important part of lipids or fats, and they can be saturated or unsaturated. A saturated fatty acid only has single carbon bonds, while an unsaturated fatty acid has one or more double bonds. Some fatty acids, including linoleic acid (omega 6) and alpha-linolenic acid (omega 3), are essential because animals, including dogs and cats, cannot make them in their bodies to meet their needs. Fatty acids play important roles in cell membranes and different systems in the body.

Omega 3 fatty acids

Omega 3 fatty acids help the cells in the body to function, especially in the eyes and the brain. Omega 3s also supply the body with energy to support systems like the cardiovascular system and endocrine system. Other than alpha-linolenic acid, there are two main omega 3s, DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid). These polyunsaturated fatty acids (more than one double bond) are especially important (and essential) for puppies and kittens, but can also help support adult cognitive, cardiovascular and immune health. 

Omega 3s are known to have anti-inflammatory properties and help support a shiny coat and also support joints. EPA and DHA are found in fish, but are also readily available in some types of microalgae. Alpha-linolenic acid is found in abundance in different types of plants, including flaxseed and canola oil. 

Omega 6 fatty acids

Omega 6 fatty acids, like linoleic acid, play an important role in brain function, help stimulate skin and hair growth, help with blood clotting and regulate metabolism. Omega 6 fatty acids do have some inflammatory properties. Inflammation is a part of tissue healing and host defense, but too much inflammation or unresolved inflammation can become an issue in the body. It is commonly believed that increasing omega 6 intake will increase inflammation in the body, however studies in healthy adult humans found that this is not the case. Scientists are still investigating omega 6 and omega 3 interactions in the context of inflammation in the body. 

Like omega 3s, omega 6 fatty acids are essential for dogs and cats, including linoleic acid, and arachidonic acid for cats. Several vegetable oils, like safflower and grapeseed oil, are rich in linoleic acid, while arachidonic acid is found in meat.

Optimal omega 6 to omega 3 ratios 

Balancing omega 3 and omega 6 fatty acids is important as one is anti-inflammatory while the other has more inflammatory properties. Too much of either type of omega fatty acids wouldn’t be great for the body. For example, too much omega 3s can cause blood thinning or excessive bleeding, and too much omega 6s can lead to chronic disorders like obesity or heart disease.

Currently, there is no perfect ratio recommended by AAFCO for dogs or cats, but they do recommend a maximum of 30:1 for omega 6 to omega 3. The National Research Council recommends a ratio of at least 2.6:1 to maximum 26:1 omega 6 to omega 3. 

In human nutrition, several studies have looked into different ratios of omega 6 to omega 3 (ranging from 2:1 - 10:1) and their effects on different conditions and diseases, like cancer and cardiovascular disease. Many have determined that an overconsumption of omega 6 and underconsumption of omega 3 is an issue in the typical Western diet.

An optimal ratio of omega 6 to omega 3 fatty acids positively affects inflammation and other biological processes, but there is no consensus as to what the ratio should be.

Check out HOPE's adult dog food, formulated for an ideal omega 6 to omega 3 ratio. 

References

Barbeau-Grégoire, M. et al. A 2022 Systematic Review and Meta-Analysis of Enriched Therapeutic Diets and Nutraceuticals in Canine and Feline Osteoarthritis. Int. J. Mol. Sci. 23, (2022).

Zicker, S. C., Jewell, D. E., Yamka, R. M. & Milgram, N. W. Evaluation of cognitive learning, memory, psychomotor, immunologic, and retinal functions in healthy puppies fed foods fortified with docosahexaenoic acid–rich fish oil from 8 to 52 weeks of age. JAVMA 241, (2012).

Hadley, K. B., Bauer, J. & Milgram, N. W. The oil-rich alga Schizochytrium sp. as a dietary source of docosahexaenoic acid improves shape discrimination learning associated with visual processing in a canine model of senescence. Prostaglandins Leukot. Essent. Fat. Acids 118, 10–18 (2017).

National Research Council. Nutrient Requirements of Dogs and Cats. Washington, D.C.: The National Academies Press; 2006.

Association of American Feed Control Officials. 2016 Official Publication. Oxford, IN: Association of American Food Control Officials Inc.; 2016.

Djuricic, I. & Calder, P. C. Beneficial outcomes of omega-6 and omega-3 polyunsaturated fatty acids on human health: An update for 2021. Nutrients 13, 2021.