Omega 3 and 6 for Dogs

What Omega-3 and Omega-6 Do for Dogs

Omega-6 and omega-3 fatty acids have many different bodily functions, including serving as a fuel source, transporting vitamins, supporting cell membranes, and aiding in cell signaling and regulation.

Because of these important functions, omega fatty acids, especially omega-3s, can be used as supplements in the management of many conditions, including cancer, skin disease, cardiovascular disease, kidney disease, gastrointestinal disease, and orthopedic diseases like arthritis.^1–3

Fatty Acids: Lipid Chains

On a chemical level, fatty acids are lipids made up of chains of carbon and hydrogen with varying numbers of double bonds.

Polyunsaturated fatty acids contain two or more double bonds in the chain and are considered “omega” based on the location of the first double bond.

Two of the most well-known omega polyunsaturated fatty acids are the omega-6 and omega-3 fatty acids.

Omega-6 fatty acids include:

• Linoleic acid (LA)
• Arachidonic acid (AA)

Omega-3 fatty acids include:

• Alpha-linolenic acid (ALA)
• Eicosapentaenoic acid (EPA)
• Docosahexaenoic acid (DHA)

Omega-6 and Omega-3 fatty acids are considered essential in the canine diet because they cannot be made and need to be ingested instead.^1,2

Sources of Fatty Acids in the Diet

Omega-6 and Omega-3 fatty acids can come from many different souces:¹

• Corn oil, peanut oil, and sunflower oil contain linoleic acid (LA) and a small amount of alpha-linolenic acid (ALA)
• Soybean oil, canola oil, and flaxseed oil contain linoleic acid (LA) and alpha-linolenic acid (ALA)
• Animal fat contains arachidonic acid (AA)
• Fish oil, sardines, salmon, mackerel, and fresh tuna contain eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)

Balancing Omega-6 and Omega-3 Fatty Acids

For optimal health, dogs should receive a balanced mixture of both omega-6 and omega-3 fatty acids in their diets.

We don’t know the ideal ratio of omega-6 to omega-3 fatty acids (if there is a single ideal ratio). But we do know a ratio of less than 5:1 can avoid symptoms of excess omega-6 fatty acids.⁴

A diet higher in omega-6 fatty acids than 5:1 can cause increased inflammation and can reduce the positive impact of omega-3 fatty acids.²

The recommended ratio of omega-6 to omega-3 fatty acids in the diet is a helpful guideline, but the total amount and type of fatty acids in the diet are just as, if not more, important.⁵

Most commercial diets contain enough omega-6 and omega-3 fatty acids to prevent nutrient deficiencies. However, their ratios can vary (see more about this below).

Effects of Too Much Omega-3 Fatty Acids

Suppose your dog is eating a commercial diet already fortified with essential fatty acids, and you want to start using an omega-3 supplement. In that case, you should discuss the supplement dosage with your veterinarian to avoid the negative effects of excess fatty acids.

Negative side effects of too much omega-3 fatty acids include:⁵

• delayed wound healing
• vomiting
• diarrhea
• weight gain
• blood clotting problems
• additional changes to immune system function

Effects of Too Little Omega-3 Fatty Acids

Fatty acid deficiencies are seen mostly in dogs eating homemade diets or diets with very low-fat content. For example, homemade diets that use beef tallow, olive oil, or coconut oil are often deficient in fatty acids.

Negative side effects of too little omega-6 and omega-3 fatty acids include:^2,6,7

• skin problems like scaling, hair loss, itchiness, bruising
• reproductive problems
• poor growth
• nervous system abnormalities

If you are using a homemade diet for your dog, you should consult a veterinary nutritionist to make sure you are using the correct type and amount of fatty acids.

Fatty Acids and Inflammation

Fatty acids form compounds connected to the responses to infection and injury, which is why they are connected to inflammation.

To simplify things, you can consider omega-6 fatty acids as “pro-inflammatory,” while omega-3 fatty acids are considered “anti-inflammatory.”

Even though “pro-inflammatory” sounds bad, the ability to initiate inflammation is an important function of the immune system. Important healing processes can’t occur without inflammation, and infections may not be managed well. This is why a deficiency in omega-6 fatty acids can result in reproductive problems, skin and coat abnormalities, and a failure to thrive.

However, too much inflammation isn’t good, either. Conditions associated with too much inflammation include arthritis, cancer, and heart disease. Fish oil is high in omega-3 fatty acids, and its anti-inflammatory benefit can be helpful in these conditions.¹

Fatty Acids and Cancer

Omega-3 fatty acids have multiple anti-cancer effects.

• If your dog is having trouble eating, supplementing your dog’s diet with omega-3 fatty acids can help improve their appetite and reduce cachexia (wasting).⁸
• They increase the immune system’s ability to find and kill cancer cells. This can mean reduced cancer development, growth and spread in the body.⁹

When omega-3 fatty acids (specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) were supplemented with the amino acid arginine, dogs with cancer had improved symptoms, quality of life, and survival time.⁹

• Omega-3 supplementation improved symptoms, survival time, disease-free interval, and improved quality of life in dogs undergoing chemotherapy for lymphoma.
• Omega-3 supplementation improved the quality of life and reduced the injury to normal tissue in dogs undergoing radiation for nasal tumors.

Omega-3 and Omega-6 in the Diet

Commercial diets for dogs already come with fatty acids to prevent nutritional deficiencies.

However, the amount of omega-3 fatty acids in commercial diets can vary and range from 0.03% to 2.5% by weight on an as-is basis. That is a wide range!

• Foods designed for dogs with arthritis or skin conditions may include more fatty acids than others.¹⁰
• Diets for dogs with cancer should contain over 5% of omega-3 fatty acids for optimal health benefits.¹¹

There are minimum dietary fatty acid requirements established per 1,000 kcal of food:¹

• Linoleic acid (LA): 2.8 grams
• Alpha-linolenic acid (ALA): 0.11 grams
• Combined eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA): 0.11 grams

Put another way, an adequate amount of (combined) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the diet is 169mg for a 22lb dog.

The exact amount of omega-6 and omega-3 fatty acids may not be listed on your dog’s food, but you can call the manufacturer for more information.

When to Supplement Fatty Acids

In general, you should avoid supplementing your dog’s diet with omega-3 fatty acids by feeding a diet already fortified and balanced. This is an economical choice and will also prevent over-supplementation.

Suppose your dog is eating a commercial diet fortified with higher levels of omega-3 fatty acids. In that case, you should call the manufacturer to ensure you will not exceed the safe upper limit of omega-3 fatty acids if you supplement.

If you are interested in supplementing your dog’s diet, consult your veterinarian to determine the correct amount of omega-3 fatty acids to give your dog.

If your veterinarian thinks your dog would benefit from more omega-3 fatty acids to improve their omega-6 to omega-3 fatty acid ratio, they may recommend a fish oil supplement. Fish oil supplements provide eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). A common supplemental dose for dogs is 50-75 mg of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) combined per 2.2 pounds of body weight daily.¹

You should be careful not to over supplement dogs with fatty acids. A safe upper limit for combined amounts of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the diet is 2,800 mg per 1,000 kcal of diet or 2,080 mg for a 22 pound dog (208 mg per 2.2 lbs).^1,5

There are many different fish oil supplements available on the market at any time, and each will show on their label how much total EPA and DHA are in a serving, and sometimes the total omega-3 fatty acid amounts, as well. Be sure to read labels.

Cautions About Omega-3 Supplements

Most dogs can tolerate fish oil supplements well, but you should remember that you are introducing a new, high-fat source into your dog’s diet. This can cause diarrhea in some dogs. Start with a low dose and gradually work up to a full dose over time.

Pancreatitis and Fish Oil Supplements

If your dog has pancreatitis, you might be concerned about giving a fatty acid supplement because high-fat foods can worsen symptoms associated with pancreatitis in some dogs.

There are no reports of omega-3 fatty acid supplements or fish oil causing pancreatitis in dogs, but they should still be used with caution in dogs with a history of pancreatitis due to their high-fat content.⁵ Be sure to ask your veterinarian about fish oil supplements if your dog has pancreatitis and follow their dosing instructions.

Carprofen and Fish Oil Supplements

You should use caution when supplementing your dog’s diet with omega-3 fatty acids if they take carprofen (Rimadyl^®) because it can increase bleeding risk.⁵

Focus on EPA and DHA

The type of omega-3 fatty acids is very important. Alpha-linolenic (ALA) acid does not have the same benefits as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), so you should read the ingredients of omega-3 supplements carefully.⁵

Avoid Cod Liver Oil

If your veterinarian has recommended giving your dog a high level of omega-3 fatty acids, you should avoid using cod liver oil. Cod liver oil contains high levels of vitamins A and D which can cause toxicity in high amounts.⁸