Leaky gut and the importance of diet for dogs with allergies by Canine Nutritionist, Narelle Cooke

What is leaky gut?

The term ‘leaky gut’ is used to describe the more formal condition of ‘gastrointestinal hyper-permeability’, which basically means that the lining of the gastrointestinal tract has become more porous than it should be.

Leaky Gut

An easy way to visualise the concept of ‘leaky gut’ is to image the gut lining as a very fine, single-layered cheesecloth that is designed to let nutrients such as vitamins, minerals and water into the bloodstream and keep larger, undigested food molecules, toxins, and pathogenic bacteria out. But when this very delicate layer is damaged – by poor diet, for example, and becomes more ‘leaky’, it is then unable to prevent undigested food particles and potentially toxic organisms from passing through into your dog’s bloodstream, where they absolutely don’t belong and are considered by the body as foreign invaders. Once this occurs, a cascade of inflammatory processes are triggered, the immune system becomes over-stimulated, and our dogs become much more susceptible to both environmental and food allergens, along with a whole raft of other potential health problems.

For example, while digestive issues and skin conditions are generally the most common symptoms that you’ll see in dogs with leaky gut, it can also manifest as chronic ear infections, joint diseases, autoimmune disorders and even behavioural problems.

It is well established that increased intestinal permeability in humans is associated with conditions such as coeliac disease, type 1 diabetes, rheumatoid arthritis, multiple sclerosis, autism, inflammatory bowel disease, asthma, chronic fatigue syndrome, liver disease and major depressive disorder. Research also shows that ameliorating leaky gut tends to reduce clinical signs and symptoms associated with disease, whereas inducing leaky gut has been shown to increase disease severity in both human and animals.

How does it occur?

There are many factors that can cause the mucosal lining of the gut to become more permeable (leaky). The overuse of antibiotics in both dogs and humans is a big one.  But what’s probably more relevant to dog owners on a day-to-day basis is the type of food they choose to feed.

If we consider our own situation, there is a lot of emerging evidence that the standard Australian diet, which is low in fibre and high in sugar, may initiate this process – which is similar to what dogs are getting when they consume highly processed commercial kibbles. Some of the reasons for this are as follows:

• Many commercial kibbles contain a long list of synthetic preservatives, additives and colours, each of which can trigger inflammation of the gut lining.
• Commercial pet foods are cooked at very high temperatures, destroying beneficial living organisms and enzymes, and thereby compromising digestion.
• The way commercial foods are processed creates a particular reaction between the proteins and the sugars (called the Maillard reaction). This particular reaction has been shown to contribute to chronic inflammatory states in the gut with subsequent negative health consequences.
• Many commercial kibbles and canned foods contain high levels of biologically inappropriate carbohydrates that our dogs are not naturally designed to eat and digest. These carbohydrates ultimately break down into simple sugar molecules in the body, feeding yeast and other harmful bacteria and contributing towards leaky gut.

Tips to prevent and heal leaky gut

The most important thing that we can do to prevent or heal a leaky gut – whether it’s for our dogs or ourselves, is to eat a more species-appropriate, whole food diet. For our dogs, this means less of those ultra-processed foods that are high in sugars and synthetic additives, and increasing the amount of:

• Higher quality, more bioavailable animal proteins.
• High quality fats such as the anti-inflammatory omega-3 fatty acids found in oily fish (i.e. salmon, sardines, and mackerel), eggs, flaxseeds, hempseeds and chia seeds. When a dog’s diet is deficient in omega-3 (or if there is too much omega-6 relative to omega-3), the immune system will react in a more inflammatory way, release more histamine, and increase your dog’s allergic tendency.
• Fresh vegetables and fruits, particularly seasonal if you can get them. Studies have shown that adding some fresh vegetables to your dog’s diet multiple times a week significantly reduces the incidence of certain cancers.
• Pre- and probiotics to strengthen the integrity of the gut, support immune function and promote overall health and wellbeing.

How raw food can help with allergies

The beauty of feeding more species-appropriate raw foods – particularly when addressing skin and allergy problems, is that they are working from the inside out to get our dogs back to their optimal state of health as quickly and naturally as possible.

Unlike the majority of commercial kibbles, most raw food companies don’t need to add anything artificial or synthetic to their foods. This means that our dogs are going to have healthier, less ‘leaky’ guts, stronger immune systems and ultimately be less prone to developing allergies and skin issues in the first place.

But if your dog is currently suffering from a skin or digestive issue and you suspect that it may be due to food intolerances, the best approach is to feed a diet that has a low allergenic potential. Reducing the allergenic load, and minimising the number of potential triggers, means that you are much better placed to figure out what might be causing the problem. It also gives your dog’s gut the time it needs to heal and function normally again.

In these instances, my key recommendation to clients is to purchase a commercial raw food formula that contains the meat, offal and bone of a single animal species (i.e. just kangaroo, just turkey or just goat), in combination with other low-reactive whole foods to support gut health and healing. I particularly like goat as a starting point for clients because for most dogs, goat acts as a novel protein (i.e. an animal protein that your dog hasn’t eaten before). The benefit of novel proteins is that they work to give your dog’s immune system a break and a chance to calm down. Turkey and kangaroo are also highly effective in these situations due to their much lower allergenic potential as compared to the more commonly fed protein sources of chicken and beef.

Final considerations when it comes to skin issues, in addition to feeding foods that reduce inflammation, is to also add in ingredients that improve your dog’s quality of life by reducing their itching and supporting the integrity of the skin barrier in order to minimise the occurrence of secondary infections. As a clinical Naturopath, nutritionist and herbalist, I highly recommend herbs such as nettle and alfalfa for reducing your dog’s itchiness, while Gotu kola is my absolute go-to herb for tissue healing and repair. Gotu kola also supports the immune system and reduces inflammation – both of which play a significant role in the development and maintenance of skin disorders and allergies in our dogs.

About the Author - Narelle Cooke, Canine Nutritionist.


Narelle is a clinical naturopath, nutritionist, herbalist and owner of the wellness clinic ‘Natural Health and Nutrition’. Narelle operates her own private practice in Sydney.

Being a lifelong dog-owner and currently meeting the demands of three French Bulldogs, a German Shepherd and a Burmese cat, Narelle is as passionate about the health and wellbeing of our pets as she is about their owners. And it was this strong desire to see her own pets live their longest and best lives that led her to hours of personal research and additional study in the area of natural animal health and nutrition.

• Bachelor of Health Science (Naturopathy) (ACNT)
• Bachelor of Agricultural Science (honours) (The University of Melbourne)
• Advanced Diploma of Naturopathy (AIAS)
• Advanced Diploma of Nutritional Medicine (AIAS)
• Advanced Diploma of Western Herbal Medicine (AIAS)
• Certificate III in Dog Behaviour and Training (NDTF)
• Certificate in Natural Animal Nutrition (CIVT)
• Certificate in Animal Nutrition (HATO)

Find out more or get in touch at https://naturalhealthandnutrition.com.au/

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