Makes Your Dog a Troublesome Thug - Here's How to Beat It

Written by Dr. Karen Shaw Becker

supplements for dogs

Story at-a-glance -

  • Recent research suggests dogs with certain behavior issues benefit supplementation with omega-3 fats, magnesium and zinc
  • The dogs in the study showed a significant reduction in fearfulness, destructiveness and inappropriate elimination while receiving the supplements
  • Processed pet food can create nutrient deficiencies, as can unbalanced homemade diets
  • You can help your dog get all the important nutrients he needs to improve both his health and behavior by feeding a nutritionally balanced, species-appropriate, fresh food diet

If you’re a regular visit here at Mercola Healthy Pets, you know that I often refer to a nutritionally balanced, species-appropriate diet as the foundation of good health. This simple but too-often ignored fact is why as a proactive integrative veterinarian, I almost always begin with a dietary review when I see a new patient.

Except in cases where an animal needs life-saving surgery or drugs, I start by improving or adjusting the diet so that we get the basics — the foundation — right. Then I take a step back and observe what kinds of changes occur in the pet’s health and behavior as a result.

Once I’m confident the animal is receiving optimal nutrition, we can move on to address any remaining physical and/or behavioral issues. In many cases, once we get the food right, there’s nothing left to address. That’s the power of a nutritionally balanced, fresh, biologically appropriate diet.

Fortunately, there’s a growing body of scientific evidence that points to the wisdom of this approach, especially as it relates to canine behavior and cognitive function. Study after study demonstrates the importance of specific nutrients in addressing the overall health and well-being of dogs and cats (and humans as well).

Study Suggests Certain Behavioral Issues in Dogs May Be the Result of Nutrient Deficiencies

One such study was published recently in the journal Topics in Companion Animal Medicine.1 A team of veterinary scientists at Ferdowsi University of Mashhad in Iran designed the study to look at the effectiveness of certain dietary supplements in treating common behavioral disorders in domestic Iranian dogs.

There were 48 pet dogs involved in the study, 42 of which had at least one behavioral issue as reported by their owners. Behavioral problems included:

  • Excessive activity
  • Inappropriate elimination
  • Fearfulness
  • Destructiveness
  • Aggression toward unfamiliar people and dogs

The six dogs with no reported behavioral issues made up the control group. All 48 dogs received the following three supplements:

  1. Fish oil capsules containing 330 mg EPA (eicosapentaenoic acid) and 480 mg DHA (docosahexaenoic acid)
  2. 12 to 15 mg/kg magnesium citrate
  3. 5 mg/kg zinc sulfate

The dogs’ owners were asked to complete four questionnaires — one at 42 days before the study began, the second on the day the study began, the third at day 84 of supplementation and the fourth at day 126 of supplementation. The questionnaires asked the dog parents if their pet had exhibited any of the listed behaviors using a scale of 0 (never or very rarely) to 4 (very often).

According to the questionnaires, the 42 dogs with undesirable behaviors had a significant reduction in the severity of fearfulness, destructiveness and inappropriate elimination. However, the owners reported no significant change in the dogs’ scores for excessive activity or aggression toward unfamiliar dogs and people.

As you would expect, there were also no significant changes in behavior in the control group of six dogs. The researchers concluded that a combination of omega-3 fatty acids, magnesium and zinc may improve some behavioral issues in dogs.

How and Why Pet Food Can Be Deficient in Important Nutrients

It’s fairly straightforward how animals eating a home-prepared diet can become deficient in key nutrients over time: owners guess at what constitutes a balanced diet and guess wrong. This is actually a very common way that nutritional deficiencies occur, with one study suggesting over 90 percent of homemade diets fed to pets are deficient.2

Many pet owners believe they can achieve “balance over time” with homemade diets, but the research is clear; the vast majority of homemade pet diets aren’t meeting minimum nutrient requirements. This is one glaring reason many veterinarians don’t support pet parents making homemade meals.

I believe homemade diets can be the absolute best or worst food you can feed your pet, depending on how much you focus on the details, including meeting vitamin, mineral and fatty acid requirements. For instance, adequate zinc intake is one of the hardest nutrients to come by using whole food sources (unless you’re feeding testicles, eyeballs, teeth, mussels, oysters or a zinc supplement daily), and the same is true for many other nutrients that our pets require. 

For a variety of reasons, dogs eating processed diets can also develop nutritional deficiencies over time. Processed pet diets are cooked at very high temperatures, which both depletes the quantity and damages the quality of the nutrients in the food.

To meet AAFCO “complete and balanced” standards, manufacturers add vitamins and minerals back into their batches of food after processing. Unfortunately, the added nutrients are typically synthetic and of very low quality, which calls into question their bioavailability (the ability of a dog’s body to derive benefit from them).

Another problem is that grain-free formulas typically contain legumes (pulse crops) such as dried peas, chickpeas and lentils. Legumes naturally contain phytates and lectins. Phytates are substances that carnivores can't break down because they lack phytase, the enzyme necessary to process phytic acid.

Phytates also bind minerals (including zinc, iron, calcium and magnesium), leeching them out of your pet's body. Lectins are sticky proteins that when consumed in large quantities may contribute to gastrointestinal (GI) disturbances and leaky gut.

Dogs eating processed diets are also often deficient in omega-3 fatty acids. Both omega-6 and omega-3 fats are very vulnerable to damage from heat. So even if these fats were once present in your pet's commercial food (as per the ingredient label), they quite likely lost their bioavailability during the kibbling or canning process.

Omega-3s are also very sensitive to oxygen and can become rancid quickly, so I prefer oils dispensed from an airless pump or that are in capsules that can be cut and squeezed onto food just prior to feeding. My last choice is to buy "pour on" oils, because there is a far greater risk of oxidation over time. If you do purchase a bottle of pourable EFAs, make sure you refrigerate them after opening and try to use up the bottle within 30 days.

As a general rule, omega-6 deficiencies are rare in dogs because commercial pet food diets typically provide too much rather than too little of these fats. If you should have a need to supplement omega-6 fats in your pet's diet (which typically occurs only if you’re feeding a homemade diet), plant oils like flaxseed, hemp and pumpkin seeds are good sources.

To boost your dog’s intake of omega-3s, you can feed sardines packed in water or wild-caught salmon, preferably sustainably sourced and toxin-free. You can also offer a krill oil supplement.

How to Make Sure Your Dog Is Optimally Nourished

The best way to ensure your dog is getting all the important nutrients she needs for optimal health and behavior is to feed a nutritionally adequate species-appropriate, fresh food diet. This means following a recipe that meets minimum (and preferably optimal) nutrient requirements or calculating these numbers yourself (which many of my empowered clients do!).

There are four primary components in a raw or gently cooked diet for dogs: meat and seafood, including a variety of organs; pureed vegetables and fruit (which supplies many hard-to-come-by nutrients); a homemade vitamin and mineral mix (in most cases, unless you’re feeding more expensive whole food sources of certain minerals); and beneficial additions like probiotics, digestive enzymes and super green foods (these aren't required to balance the diet, but can be beneficial for vitality).

A healthy dog's diet should contain about 85 percent meat/organs/bones and 15 percent veggies/fruits (this mimics the GI contents of prey, providing fiber and antioxidants as well key nutrients). This base is an excellent starting point for recipes, but it’s far from balanced and shouldn’t be fed long term without addressing its significant micronutrient deficiencies.

Fresh, whole food provides the majority of nutrients dogs need, but the vast majority of homemade diets are still deficient in iron, copper, manganese, magnesium, zinc, iodine, vitamins D and E, folic acid and taurine (depending on what protein and organs are used).

To offset cost, many pet parents opt to use vitamin and mineral supplements to meet their pet’s minimum nutrient requirements for homemade diets. If you opt not to use supplements, you must add in whole food sources of these nutrients, which requires additional money and creativity.

Of course, there can be issues with oversupplying minerals (including zinc and magnesium) as well. I don’t advocate owners add additional minerals to their pet’s diet, above and beyond meeting optimal nutritional requirements, as over-supplementation is as detrimental as under-supplementation.

This research highlights the importance of making sure the nutrients in your pet’s diet are bioavailable (not always the case with highly processed commercial pet foods) and supplied in species-appropriate amounts (not always the case with homemade diets).