Glossary

Omega-3 fatty acids

Fats, especially EPA and DHA from fish oil, that may calm inflammation and support skin, joints, heart and brain; the right amount is a vet decision.

Also called: omega-3, fish oil for dogs, EPA and DHA, omega 3 supplement, krill oil

Omega-3 fatty acids are essential fats that dogs must get from food. The forms that matter most are EPA and DHA, found in fish and fish oil, krill and some algae. Plant sources such as flaxseed supply ALA, which dogs convert poorly to EPA and DHA.

They are used to support skin and coat in allergic dogs, joint health in dogs with arthritis, and the heart and kidneys, and DHA helps puppy brain and eye development. Evidence is strongest for joint and skin benefits, and many therapeutic diets include extra.

More is not better. Too much can cause loose stool, bleeding tendency, weight gain or vitamin problems, and products differ greatly in strength and freshness, so look for third-party testing. Ask a veterinarian which product and amount suit your dog, especially before surgery or with other medications.

Last reviewed November 8, 2026

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