How much omega-3 does my dog actually need?

There's no single magic number, and it depends on your dog's size, age, and whether you're feeding for general health or a specific concern like itchy skin or stiff joints. As a rough guide, most healthy dogs do well on somewhere around 50 to 75mg of combined EPA and DHA (the two omega-3s that actually matter) per kilo of body weight a day. Dogs working through skin, coat or joint issues are often fed more, sometimes two to three times that, but that's a conversation to have with your vet rather than a DIY calculation.

The more useful thing to understand is where it comes from. EPA and DHA are the active marine omega-3s, found in fish and green-lipped mussel. Plant sources like flaxseed give you ALA, which dogs convert to EPA and DHA very poorly, so a food that leans on flax for its omega-3 claim isn't doing much. Look for named marine sources on the label.

If your dog's already on a food that includes green-lipped mussel or fish oil, you're likely covering the baseline without needing to add anything on top. If you do supplement, introduce it slowly, keep an eye out for loose stools, and don't overdo it, because more isn't automatically better. When in doubt, your vet can point you to the right amount for your dog.