Allergies and autoimmune diseases are increasing rapidly among our beloved dogs. There are at least three related theories to explain this.
#1: The “Hygiene Hypothesis”
The "hygiene hypothesis" notes that dogs on immunosuppressive medicines and protected from germs and parasites end up vulnerable, as their immune systems don't "learn" to distinguish friend from foe.
#2: The “Epithelial Barrier Hypothesis”
They are exposed to various chemicals in the air, food, and water: microplastics, ozone, pesticides, exhaust fumes, cigarette smoke, and more. These substances weaken the particular, sheet-like tissue called epithelium that lines their stomach, esophagus, and intestines. The idea that damage to this tissue can trigger allergies is sometimes called the "epithelial barrier hypothesis." Toxic exposures may also explain autoimmune illness. For example, if the lining of the intestine is weakened, a condition called "intestinal permeability" or "leaky gut," it can't completely do its job of protecting the gut. The altered environment sets off systemic chronic immune reactions.
#3: Hyper-processed Foods
The dog's diet of increasingly and solely hyper-processed foods is changing the balance of microorganisms in their bodies, collectively known as the microbiome, which harms efficient immune function.
This rendering of a "leaky" intestinal junction shows how broken-down food particles that should remain within the digestive tract can escape into the vascular system. Antibodies interpret the particles as pathological invaders, ramping up inflammation to chronic, unhealthy levels.
A leaky gut combined with intestinal imbalance may contribute not only to autoimmune illness to other diseases afflicting Americans, such as diabetes, obesity, Alzheimer's, autism spectrum disorder, and depression (Bodenmueller, 2021; Akdis, 2021). It also contributes to behavior issues, cancer, growth potential in puppies, and longevity.
The good news is that consuming omega-3s plentiful in fatty fish appears to help protect us. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are incorporated into the cell membrane, helping to prevent it from becoming too permeable or leaky (Durkin et al., 2021).
So what's the most fundamental cause? Increasingly, researchers are focusing on the gut.
What You Didn’t Know about Your Dog’s Gut
The gut barrier is the largest interface separating any part of our "insides" from the outside world.
The epithelial cells that line the gut take up nutrients and water and regulate other responses to nearby cells, communicating with gut bacteria and intestinal immune cells (Akdis, 2021). But epithelial cells move and change shape, and sometimes the junctions between them can develop gaps. A built-in system triggers local repairs to keep the barrier consistent. You can see this process in action (in a frog embryo) here. (Erickson, 2019).
If these repairs aren't made, the gut becomes vulnerable. This may happen, for example, when the gut epithelial cells are exposed to chemicals as common as emulsifiers in processed food in small amounts (Akdis, 2021).
Overall our dog's diet affects how well the barrier functions. Vitamins C, D3, and E, flavonoids (See "Eat the Rainbow" for a description of these nutrients in fruits and vegetables), the short-chain fatty acids that digest fiber, and some polyunsaturated fatty acids, including omega-3s, all appear to protect it and thus affect our dog's immunity.
The Volhard Rescue diet is a one-of-a-kind formula. It is a dehydrated functional food blend developed by Wendy Volhard, which is anti-inflammatory, hypoallergenic, grain, and gluten-free! Rescue is crafted in small batches with whole food ingredients and herbs to support the liver, kidney, heart, lungs, stomach, and digestive tract.
Holistic Proactive Veterinarians agree that a fresh, healthy, and balanced higher protein, low-glycemic diet that includes functional foods can help dogs reduce inflammation while preventing, managing, and overcoming severe health conditions.
When mixed with 80/20 beef and water, the foundation mix provides a complete and balanced diet for dogs suffering from sensitivities to grains, experiencing chronic ear and skin inflammation and inflammatory diseases, and needing food low on the glycemic index.
The best way to get EPA and DHA omega-3s is by eating seafood, especially fish like wild-caught salmon, mackerel, and sardines. You can also take Volhard's Krill oil supplement to get what your dog needs in a small amount. Volhard recommends feeding fish as the protein choice at least one day a week to let the dog's body rest from digesting muscle meat and supplying it with Omega-3's.
A recent overview of more than 80 studies analyzing the effect of these fatty acids on inflammatory bowel disease or inflammation markers concluded that increased consumption of omega-3s for at least six months could cut the risk of relapse or worsening cases (Ajabnoor et al., 2020).
Beyond the Gut
Epithelial damage from everyday chemicals may accumulate. In the past 20 years, researchers at the Swiss Institute of Allergy and Asthma Research linked to the University of Zurich have investigated how various substances damage the protective epithelial cells of several organs. Not just the gut but the skin and upper and lower airways are affected.
For example, common ingredients in laundry detergent, soap, and shampoo disrupt the epithelial layer of the skin and bronchial tubes even when highly diluted, reports Director Cezmi Akdis, editor of the journal Allergy (Akdis, 2021). He notes research showing that nurses exposed to medical disinfectants tended toward asthma.
Microorganisms settle in tissues behind leaky epithelial tissue, displacing friendly bacteria and triggering inflammation, setting off bad feedback loops, Akdis explains. Stimulated by the altered environment, immune T cells can overreact throughout the body, such as when children sensitive to milk develop skin rashes. Germs like staphylococcus aureus get behind the barrier in the skin and nose and overgrow, leading to aggravated asthma and rashes.
Staphylococcus Aureus. Source: https://www.biomerieux-industry.com/pharma-health...
What Can You Do about All of This?
Let's say your dog reacts badly to wheat, even though they don't have the autoimmune problem celiac disease. Research suggests that the dog may have a leaky gut triggering an inflammatory reaction (Uhde, 2016).
Besides avoiding wheat, you could think about your dog's chronic chemical exposures and try to limit them. You could also see your dog's wheat problem as a sign that they need a better overall diet, including more omega-3s, ideally from marine sources like wild-caught salmon and shellfish. Make sure your wheat ingredients are human grade and Non-GMO!
The good news is, a battered epithelium wants to repair itself. Give it the proper diet and environment and it will begin to do so.