Is Your Dog Missing This Essential Trace Mineral?

I had the pleasure of speaking with Kristin Clark, animal naturopath, author of Raw and Thriving, and founder of the Raw Pet Digest magazine. Kristin and I discussed something she has recently become very passionate about, zinc deficiencies. After our discussion I was intrigued to do some more research, this post is a combination of that research and my chat with Kristin.

Zinc is an essential mineral that plays a role in cell division, cell growth, and wound healing. It is classed as “essential” because it cannot be synthesized in the body and must be supplied in the diet. Zinc also stimulates enzymes in the body and is crucial for a healthy immune system (1). In fact studies in humans have shown that “zinc supplementation decreased oxidative stress markers and generation of inflammatory cytokines” (2). While zinc deficiencies are more commonly seen in northern breeds like huskies or malamutes (as they have a genetic predisposition to poor zinc absorption), Kristin posits that they are a “silent killer” for dogs of all breeds, ages, and backgrounds.

A Little More About Zinc

“Zinc is the second most commonly used mineral in your dog’s body. Zinc a powerful antioxidant and aids in various metabolic processes in the body. Zinc works by itself and with other nutrients, such as copper, B-complex vitamins, vitamin A, calcium, and phosphorous, to support the body and aid in different essential bodily functions.

Here’s the kicker: even though zinc is one of the most important trace minerals, the body has no way to store zinc. That means the body needs a regular, adequate supply of zinc; if it doesn’t get this, it will become deficient in zinc” (3).

Signs of Deficiency

The signs of zinc deficiency are varied and range in severity from mild to fatal. Some people look at zinc deficiencies in stages, with dogs in the first stage exhibiting mild symptoms to dogs in the final stages going into organ failure and experiencing seizures which will ultimately lead to death.

Stage One: Digestive issues (including diarrhea, and appetite decline), dull coat and/or hair loss. Food allergies are often blamed as the cause at this stage.
Stage Two: Patches of crusty, raised skin known as zinc dermatosis appear. These can be mistaken for hot spots.
Stage Three: The immune system begins to suffer by underperforming or overreacting. The results of this can be extremely diverse.
Stage Four: the thyroid becomes involved and beings to malfunction. This can cause rapid changes in weight, behaviour, appetite, and can sometimes cause a persistent cough.
Stage Five: Organ failure, usually of the kidneys, liver, and heart
Stage Six: Seizures caused because without adequate zinc levels the taurine needed for brain function cannot work

If you suspect your dog has a zinc deficiency you can as a vet familiar with the condition to check zinc levels via hair or blood serum analysis.

Is There Really Enough Zinc in Your Dog’s Food?

The question you need to ask probably isn’t is there enough zinc in my dog’s food, but actually how much zinc is my dog actually able to absorb from his food.

This question is exceptionally relevant to you if you are feeding a kibble-based diet, especially one that contains a high amount of plant proteins like lentils, corn, peas, rice, soy, wheat (listed in descending amounts of phytic acid content (4)). This is because phytic acid, a substance found in all edible seeds, grains, legumes, and nuts, has a negative effect on mineral absorption, including zinc.

One study done on minks, a carnivorous mammal, showed that mineral absorption was “significantly reduced” with increasing concretions of phytic acid (5). In short, the higher the phytic acid content of the food, the less zinc the body is able to absorb from it. In other words, the higher the plant protein content of your food the more likely it is that your dog is not getting adequate levels of zinc from it.