So I was asked a really good question this week about healthy oils for dogs …
Recently, an integrative vet published an interesting article online. In it, she said that dogs can’t convert plant-based Alpha Lipoic Acid (ALA) to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). She said dogs don’t have the enzymes needed to do this, so they should get fish oil or krill oil, not plant oil.

Yes, dogs need these essential fatty acids in their diets. But I wanted to respond to this statement because I think it’s important.
** I also thought the answer was important enough to jump on a quick Facebook Live and share it with you. Homeopath and owner of Adored Beast Julie Anne Lee joined me! Here’s the video:
Healthy Oils For Dogs
EPA is very important to your dog’s health. It competes with inflammatory omega-6 fatty acids for receptor sites and decreases inflammation.
DHA makes healthy cell membranes, especially in nerve cells. This makes it especially good for brain and eye health.
Now, EPA and DHA are the more bioavailable forms of ALA, a main omega-3 fatty acid. ALA is found in grass-fed animals and plant oils. These contain ALA, which is the precursor of EPA and DHA, but not EPA and DHA themselves. In order to reap the benefits, dogs have to convert them. But fish and marine oils contain ALA plus EPA and DHA, and that’s why they’re so popular.
What The Research Says
Why did the vet I mentioned say that dogs can’t convert ALA? Well, researchers compared plant-based ALA and ALA from fish oil. Then they looked at the inflammatory markers in both groups. They found that the fish oil had a bigger impact on inflammatory markers. And they found that dogs can convert ALA to EPA, but just a small amount. And they also produced a DHA precursor called DPA, but not much DHA.
But wait, taking this research and saying dogs lack the enzymes needed for conversion is a stretch. The dogs DID convert it. The researchers just thought it wasn’t enough. They saw bigger changes in inflammatory markers if the dogs were fed EPA and DHA along with ALA. The scientists just said they didn’t know if the amount is enough to control inflammation.
So, let’s be clear on this point first: dogs do have the enzymes they need to convert ALA to EPA and to a DHA precursor.
But here’s the thing about nutrition – and why we shouldn’t make blanket statements like “dogs can’t convert ALA to EPA and DHA.” There’s far more that we don’t know about nutrition than what we do know. And that’s because it’s really hard to make studies that really measure what we want them to.
And this study is a perfect example.

The dogs in those studies were fed kibble … and kibble is very high in inflammatory omega-6 fatty acids. The dogs were already dealing with too much inflammation. And it’s probably true that in that case, they couldn’t manufacture enough EPA to curb it. Both omega-6 and omega-3 fats compete for the same receptor sites. If there’s too much omega-6 in the diet, you’ll never be able to get enough omega-3 in there to compete with it.
The problem might NOT be that the dogs couldn’t manufacture enough EPA. The problem could be that they couldn’t make enough EPA to make up for the omega-6 orgy in their kibble diet.
And research actually shows this is the case. Diets high in Linoleic Acid (LA), a primary omega-6 fat, can decrease ALA conversion by as much as 40%. Trans fats, which are the result of high temperature cooking, can also reduce the conversion of ALA to EPA and DHA.
And high intakes of EPA and DHA and even ALA can decrease the conversion rate. So if you’re giving your dog a lot of fish oil, you could be limiting his ability to convert ALA into EPA and DHA. That’s right … his body will rely on that supply and stop trying to convert it.
But there’s something else that’s really important to remember here … the microbiome.
Inside Your Dog’s Gut
The studies the integrative vet was referring to are a decade old or more. Sure, that isn’t old, but it was before scientists really started looking at the microbiome. We’re now far more aware of how it impacts immunity, inflammation and nutrition.
The microbiome is made up of populations of bacteria and microorganisms that live on and in your dog. And an important microbiome is the one that lives in your dog’s gut.
The bacteria that live there outnumber your dog’s cells 10:1. These little friendly bacteria populations have a mutually beneficial relationship with your dog. They eat what your dog eats – and they poop out little metabolites that can:
- talk directly with your dog’s brain
- help control his immune system
- provide many of his vitamins
- provide really important short chain fatty acids that also help control inflammation
Plus, they compete with pathogenic bacteria for attachment sites and crowd them out. This includes things like E. coli, salmonella and Bordetella!
And, most importantly, their metabolites produce enzymes.
Remember I said those bacteria eat what your dog eats? New research shows that these bacteria produce metabolites that can stimulate the conversion of ALA to EPA and DHA. That’s the good news.
But if your dog eats a lot of starch (kibble) it will feed bacteria that like to eat starch. And these bacteria will start to grow out of control. They’ll compete with the bacteria that metabolize fats (like ALA) and reduce their ability to convert them to EPA and DHA.
The graph below is preliminary. It’s from a study that hasn’t been published yet, but I asked Drs Richard Patton and Holly Ganz about the results they’d found so far and they agreed to share them.

In this study, Dr Patton and Dr Ganz fed dogs kibble and took fecal samples. Then they took half the dogs and put them on a freeze-dried raw food for 2 months and left the other half on the kibble diet. They then compared the fecal samples from both groups of dogs …
… and you can see the bacterial populations were vastly different. The populations of bacteria shifted a huge amount based on the diet fed to the dogs. If the dogs eat a diet high in starch, the starch-eating bacteria species will grow. If the diet is high in fat, the fat-eating species will grow.
Why am I telling you all of this? Because nutrition isn’t black and white.
[RELATED] Fecal transplants are becoming the ultimate healer for dogs with microbiome issues.
What’s The Answer?
First off, dogs most definitely do have the enzymes to convert ALA to EPA, because they do convert it. But feeding an omega-6 rich diet like kibble seems to suppress those enzymes by up to 40%. And adding EPA and DHA to the diet also seems to suppress those enzymes. And a starch-rich diet might also reduce the number of bacteria that help convert ALA to EPA and DHA.
So, what’s the answer? Don’t feed your dog an unnatural diet like kibble. Dogs aren’t designed to deal with a diet that’s 30% starch or more … and a diet that’s high in omega-6 fatty acids. This changes their bacteria populations, the metabolites and enzymes they produce, and the enzyme activity in your dog.
If you’re going to feed your dog kibble, then I guess you should slather krill oil all over it. But I suspect if you’re reading this, you want to do better for your dog.
The best way to make sure there’s a balance between omega-6s and omega-3s is to feed the right foods, in the right amounts. That means little to no starch, a good amount of protein and about 10-20% fat.
In the end, it’s not as simple as saying dogs should eat fish oil because they don’t have the enzymes to convert ALA. Nutrition is never that easy. And that’s why it’s always best to stick to what mother nature made for your dog to eat: healthy, raw, whole foods – and that means a variety of healthy oils for dogs.
References
J John E. Bauer, DVM,
Menni C et al., “Omega-3 Fatty Acids Correlate With Gut Microbiome Diversity And Production Of N-
Emken EA et al., “Dietary Linoleic Acid Influences Desaturation And Acylation Of Deuterium-labeled Linoleic And Linolenic Acids In Young Adult Males,” Biochim Biophys Acta Vol 1213 (1994).
Al MD et al., “Fat Intake Of Women During Normal Pregnancy: Relationship With Maternal And Neonatal Essential Fatty Acid Status,” The Journal of the American College of Nutrition Vol 15 (1996).
Elahe Abedi and Mohammad Ali Sahari, “Long-chain Polyunsaturated Fatty Acid Sources And Evaluation Of Their Nutritional And Functional Properties,” Food Science & Nutrition Vol 5 (2014).