What are Omega-3s?
Omega-3s are a type of polyunsaturated fatty acid (PUFA) found in both human and pet diets that can play a vital role in maintaining overall health. Omega-3 fatty acids are different from other PUFAs as they consist of a carbon-carbon double-bond near the chain’s methyl group (Figure 1). Common omega-3s include alpha-linoleic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). ALA is a short chain omega-3, while EPA and DHA are both long-chain omega-3s. These differences give the fatty acids unique biochemical properties and affect how they work in the body. Omega-3 fatty acids do not operate alone but work in unison with another class of PUFAs known as omega-6s. The relationship between omega-3 and omega-6 fatty acids is important in maintaining your pets’ basic nutritional needs, and in preventing excess inflammation.
Figure 1: The chemical makeup of common omega-3 fatty acids.
Why are Omega-3s important?
Dietary fats are important for overall health as they can help support energy production, maintain cell membranes, immune function, growth, metabolism, and the absorption of fat-soluble vitamins A, D, E and K. Omega-3 fatty acid ALA is required in the daily diet, since the body cannot produce it. ALA is important in maintaining the skin’s water barrier, as well as keeping your pets’ coat healthy and shiny. EPA and DHA can be produced from ALA in the body, but the amounts made are not enough to see beneficial effects. Thus, supplementation of EPA and DHA is often done to observe their benefits.
More specifically, DHA and EPA can provide anti-inflammatory effects, which can help pets with inflammatory diseases such as osteoarthritis, diabetes, skin allergies and dermatitis, kidney disease, heart disease, and cancer. If you are interested to learn more about the role of omega-3s in treating osteoarthritis, check out our previous blog post, Joint Pain in Pets – How to Recognize and Treat Osteoarthritis.
Not only can omega-3s aid in decreasing inflammation, but they have also been shown to have pain-relieving properties. A review of 72 trials involving omega-3-enriched diets and supplements for dogs and cats found evidence that they can help relieve pain. There are also indications of omega-3s being beneficial for senior pets; research has demonstrated omega-3 supplementation slowing retinal degradation, improving brain function, regulating the immune system, and improving insulin sensitivity.
Omega-3s in Your Pet’s Diet
The National Research Council (NRC) and Association of American Feed Control Officials (AAFCO) both have minimum and maximum requirements of omega-3s depending on your pet’s life stage. Table 1 depicts common sources of omega-3s found in most dog and cat pet foods.
Table 1: Common ingredients used in pet foods and their omega-3 sources.
| ALA | EPA | DHA | |
| Corn Oil | ✓ | ||
| Canola Oil | ✓ | ||
| Flaxseed or Flaxseed Oil | ✓ | ||
| Soybean Oil | ✓ | ||
| Fish Meal or Fish Oil | ✓ | ✓ | ✓ |
| Algal Oil | ✓ | ✓ | ✓ |
Commercial Diets
Commercial dog and cat foods that are made to be complete and balanced are a great way to meet the omega-3 needs of your pet. These diets typically contain higher amounts of ALA through the source of flaxseed or canola oil, which is later converted to EPA and DHA in the body. When feeding a commercial diet, you might want to consider supplementation of EPA & DHA with an omega-3 product such as fish oil to increase the amount of omega-3s in your pet’s diet.
Veterinary Therapeutic Diets
Veterinary therapeutic diets are formulated to help manage various diseases, while also being complete and balanced. They meet your pet’s omega-3 needs, but those aimed at supporting joint, skin, heart or kidney health typically provide extra omega-3s. These diets generally have higher amounts of EPA and DHA, often using ingredients like fish oil more than standard commercial diets. Generally, veterinary therapeutic diets are only sold by veterinarians, so it is important to consult with your family vet.
Supplementation
Although omega-3s are present in most pet foods, you may want to supplement more to your pet’s diet to get the full benefits these fatty acids can provide. Omega-3 fatty acid supplements can come in various forms including oils, capsules, and treats. Please note that various conditions require different amounts of omega-3 oils, so it is very important to consult with your veterinarian to get more information on dosing based on your pet’s specific needs. When choosing a supplement, it is important to choose from a reputable company that can provide a list of all ingredients within the supplement and their quality control protocols. It is recommended to call the manufacturer or consult with a third-party evaluator company if you are unsure about these quality control practices.
Omega-3 Deficiencies
If you are feeding your pet a complete and balanced diet, then they are at less of a risk of developing an omega-3 fatty acid deficiency. Although signs of fatty acid deficiency may include the following.
- Skin & coat problems: This includes symptoms such as coarse coat, dry flakey skin, and hair loss.
- Vision loss: In cases of severe omega-3 deficiencies, it is common to have deterioration of the retina. This deterioration can lead to vision loss and thus poor eyesight.
Overconsumption of Omega-3s
Omega-3s can provide your pet with several benefits, but it is important to keep in mind that too much of a good thing can lead to potential problems. Symptoms of excess omega-3s may include the following.
- Weight gain: Since omega-3s are a source of fat, over-supplementation can lead to weight gain and, over time, lead to obesity.
- Gastrointestinal symptoms: These symptoms include vomiting and diarrhea. With any diet high in fat, pancreatitis becomes a concern. Though there are no reported cases of pancreatitis caused by therapeutic fish oil administration, it is important to consult with your veterinarian about supplementation dosing.
- Toxin exposure: Supplementation of fish oils like salmon or cod may contain trace amounts of heavy metals, which when fed in excess can cause toxin exposure. It is important to source supplements from companies that can provide a list of what the supplement contains and ensure the company can explain their quality control protocols.
- Lipid peroxidation: This chemical process refers to the oxidative deterioration of fats by a reactive oxygen species, leading to the breakdown of fats within the cell membrane and cell death. Although clinical signs of lipid peroxidation are unclear, studies have shown lipid peroxidation presents as a vitamin E deficiency, which includes muscle weakness, and loss of vision.
Omega-3s are very important and can provide the necessary fats to keep your pet healthy and help with inflammatory diseases. Side effects including gastrointestinal upset are usually only shown due to over supplementation and are easily resolved by lowering or removing the omega-3 supplementation. If you have any concerns about omega-3s in your pet’s diet, please contact your veterinarian.
Written By: Julia Iaboni BScH, Class of 2025
Reviewed By:
Brooklynn Liversidge MSc, PhD Candidate
Dr. Adronie Verbrugghe DVM, PhD, EBVS® European Specialist in Veterinary and Comparative Nutrition (Dip ECVCN), Associate Professor and Royal Canin Veterinary Diets Endowed Chair in Canine and Feline Clinical Nutrition
Dr. Sarah K. Abood, DVM, PhD, Associate Professor, Nestlé Purina Professorship in Companion Animal Nutrition
References:
Burron, S., Richards, T., Krebs, G., Trevizan, L., Rankovic, A., Hartwig, S., Pearson, W., Ma, D. W. L., Shoveller, A. K., The balance of n-6 and n-3 fatty acids in canine, feline, and equine nutrition: exploring sources and the significance of alpha-linolenic acid. Journal of Animal Science. 2024; 102 https://doi.org/10.1093/jas/skae143
Lenox, C. E., Role of Dietary Fatty Acids in Dogs and Cats. ACVN. 2016.
Lenox, C. E., Bauer, J. E., Potential Adverse Effects of Omega-3 Fatty Acids in Dogs and Cats. Journal of Veterinary Internal Medicine. 2013; 27 (2): 217-226 https://doi-org.subzero.lib.uoguelph.ca/10.1111/jvim.12033