Why EPA Wins

EPA stands for eicosapentaenoic acid, a long-chain marine omega-3 fatty acid found primarily in fish oil and algae-derived marine oils. Among the omega-3 fatty acids, EPA has been extensively studied for its ability to support a healthy inflammatory response throughout the body, making it an important nutrient in both human and veterinary nutrition.

Why EPA Is So Important

EPA is considered a biologically active omega-3 because it becomes incorporated into cell membranes throughout the body. Once there, it helps shift the body's production of signaling molecules away from more pro-inflammatory compounds and toward specialized pro-resolving mediators, including E-series resolvins. This is one reason EPA-rich diets and supplements are commonly recommended to support skin health, joint function, cardiovascular wellness, and other conditions involving chronic inflammation.

EPA vs. Plant-Based Omega-3s

Not all omega-3 fatty acids function the same way. Many plant-derived omega-3 supplements contain ALA (alpha-linolenic acid), which is found in flaxseed, chia seeds, and certain vegetable oils. While ALA is an omega-3 fatty acid, both dogs and humans convert only a small percentage of ALA into the biologically active marine omega-3s EPA and DHA.

Because of this limited conversion, marine-derived EPA and DHA generally produce greater increases in tissue omega-3 levels and have stronger evidence supporting their effects on inflammatory health than ALA alone.

EPA Compared with DHA

EPA and DHA are complementary marine omega-3 fatty acids, but they are not identical. EPA is often emphasized when the primary goal is supporting a healthy inflammatory response, particularly for skin, joints, and other inflammatory conditions. DHA, meanwhile, plays especially important roles in brain development, retinal health, and nervous system function.

Research suggests that EPA may provide greater benefit for certain inflammatory pathways, while DHA may perform equally well—or even better—for other biological functions. Rather than competing, EPA and DHA often work best together, with the ideal balance depending on the health goal.

EPA and Canine Skin Health

Veterinary dermatology has accumulated substantial evidence supporting marine omega-3 supplementation for dogs with inflammatory skin conditions. Studies have shown that EPA-containing supplements may help support dogs with allergic skin disease, itching, inflammatory dermatitis, and poor coat quality. As tissue levels of marine omega-3 fatty acids increase, many dogs experience healthier skin and improved coat condition.

Omega-3 vs. Omega-6

Although omega-3 fatty acids receive much of the attention, omega-6 fatty acids remain essential nutrients. Dogs require linoleic acid, an omega-6 fatty acid, for maintaining a healthy skin barrier, normal coat quality, and overall integument health.

The goal is not to eliminate omega-6 fats but to maintain an appropriate balance between omega-6 and omega-3 fatty acids. Most commercial dog foods already contain adequate—or even abundant—amounts of omega-6 fats, whereas EPA and DHA are often present in much lower quantities unless marine oils are specifically added.

For this reason, supplementing EPA-rich marine omega-3s is often more beneficial than adding additional omega-6 fats to an already omega-6-rich diet.

What About Omega-9?

Omega-9 fatty acids, such as oleic acid found in olive oil, can certainly contribute to a healthy diet. However, unlike omega-3 and omega-6 fatty acids, omega-9s are not considered essential fatty acids because dogs and other mammals can produce them naturally.

As a result, omega-9 supplementation is generally not considered a primary therapeutic strategy in veterinary nutrition when compared with marine omega-3s.

A Practical Clinical Perspective

• Marine omega-3 fatty acids are among the best-supported nutritional supplements for helping maintain a healthy inflammatory response.

• EPA-rich products are often preferred when supporting skin, joints, and other inflammation-sensitive tissues.

• Omega-6 linoleic acid remains essential for maintaining a healthy skin barrier and coat but is usually already supplied in sufficient amounts by commercial diets.

• Omega-9 fatty acids can contribute to overall nutrition but are generally not considered essential supplements for dogs.

The Takeaway

EPA is not a miracle nutrient, but it is one of the most biologically active and well-researched fatty acids available in veterinary nutrition. Compared with plant-derived omega-3 sources, marine EPA has stronger scientific support for promoting a healthy inflammatory response and supporting skin, coat, joint, and overall wellness. When used appropriately as part of a balanced diet and veterinary care plan, EPA-rich marine omega-3s provide meaningful nutritional support for dogs throughout every stage of life.