Leaky Gut in Dogs: Causes, Signs, and Natural Ways to Heal the Gut

When I first started rescuing senior dogs, almost every single one of them came to me sick. I saw countless dogs with itchy skin, allergies, diarrhea, ear infections, anxiety, and chronic inflammation. At the time, I didn’t realize what all those symptoms had in common, but now I do: most of these dogs’ issues were caused by leaky gut in dogs, because of a damaged digestive system.

Like many well-meaning pet parents, I made the same mistake most people do, I jumped on the probiotic and prebiotic bandwagon. I thought I was helping their digestive systems, but instead, I made it worse. Their guts were already inflamed, and adding bacteria to an unbalanced, damaged environment was like throwing seeds into dry, toxic soil. Nothing could grow right without the right foundation.

That’s when I went back to the basics — food, fungi, and adaptogens.

I started feeding beneficial foods that would help heal their gut and immune system. I used medicinal mushrooms to help repair the microbiome naturally. And I added adaptogens to help their bodies handle the stress and inflammation that had been building for years. 

What is Leaky Gut? 

The gut lining is your dog’s first line of defense, a tightly sealed barrier that keeps the good stuff in (nutrients) and the bad stuff out (toxins, pathogens, undigested particles).

When that lining becomes damaged or inflamed, the junctions between the intestinal cells open. That’s called leaky gut or increased intestinal permeability. Once that happens, toxins, bacteria, and proteins “leak” into the bloodstream and trigger the immune system to go into overdrive.

Over time, this leads to systemic inflammation, which becomes the root of most chronic issues in your pet: skin allergies, autoimmune disease, joint pain, digestive upset, and even anxiety.

What I see most often is that dogs start with a small trigger, whether it’s antibiotics, kibble, flea meds, or stress, and within months, their entire system is out of balance. The gut stops absorbing nutrients, the immune system starts attacking the body, and their endocannabinoid system struggles to keep up.

Signs of Leaky Gut in Dogs

Leaky gut shows up differently in every dog, but here are the most common red flags I’ve seen over the years:

• Chronic itching, hot spots, or recurrent skin infections
• Allergies that never seem to resolve 
• Gas, bloating, diarrhea, or constipation
• Recurrent ear infections
• Joint stiffness or arthritis especially in a younger dog
• Anxiety or behavioral changes
• Chronic fatigue or low energy
• Autoimmune or inflammatory disease
• Poor response to supplements or diet changes

If your dog keeps struggling no matter what you try, there’s a good chance the problem starts in the gut.

What Causes Leaky Gut in Dogs?

Here are the top five root causes I see when it comes to leaky gut in dogs, and what you can do to start turning things around.

Processed Diets & Lack of Whole Foods and Fiber

Kibble and “fortified” pet foods are loaded with synthetic vitamins, fillers, and chemical preservatives that dehydrate and inflame the gut lining. They destroy the good bacteria your dog needs to stay healthy.

Medications & Synthetic Additives in Supplement

Antibiotics, steroids, antacids, and NSAIDs damage the mucosal barrier and alter the microbiome. Additives and isolates in supplements are just as harmful by stressing the liver and disrupt digestion. If your dog must take medication, always support detox pathways and help rebuild the gut lining.

Chemical Toxins

Pesticides, lawn sprays, cleaning chemicals, and even tap water can damage the gut lining. These toxins destroy beneficial bacteria and weaken the immune system. Reducing chemical exposure is one of the fastest ways to support gut repair.

Food Sensitivities & Inflammatory additives

Many dogs are sensitive to chicken, beef, dairy, and soy and these ingredients are used in most processed foods, and treats. Over time, repeated exposure triggers immune reactions that inflame the gut.

Aging & Enzyme Decline

Older dogs naturally produce fewer digestive enzymes and less stomach acid, which leads to poor digestion and fermentation. That irritation causes inflammation and nutrient loss.

Natural Ways to Heal Your Dogs Leaky Gut

Once you understand what causes leaky gut, you can start taking steps to help fix it naturally, gently, and effectively.

1. Start with Real Food

Feed a fresh, organic, species-appropriate diet that’s rich in moisture, enzymes, and natural fiber. Fresh food supports proper pH, bile flow, and microbial balance. This includes vegetable fiber.

2. Use Functional Mushrooms to Rebuild the Microbiome

Mushrooms are one of nature’s perfect gut foods. They act as pre-, pro-, and postbiotics — feeding beneficial microbes, balancing immune responses, and reducing inflammation.

• Turkey Tail supports microbial diversity.
• Reishi calms inflammation and helps the liver detox.
• Lion’s Mane regenerates nerve and gut lining cells.
• Shiitake provides natural enzymes for digestion.

3. Add Adaptogens to Restore Balance

Adaptogens like Rhodiola, Ashwagandha, and Holy Basil help regulate stress hormones, improve oxygenation, and support the gut-brain axis. Stress and cortisol are major contributors to leaky gut, and adaptogens help the body stay in balance under pressure.

4. Support the Endocannabinoidome

The Endocannabinoid system (ECS), or what researchers now call the Endocannabinoidome, includes the ECS and the gut microbiome working together to maintain homeostasis. There are cannabinoid receptors all throughout the gut that regulate inflammation, motility, and immune responses. 

A full-spectrum hemp extract helps restore endocannabinoid tone and supports a healthy, sealed gut barrier, especially when paired with fungi and other adaptogens.

6. Soothe and Repair with Herbal Allies

Herbs like slippery elm, marshmallow root, aloe vera, milk thistle, and dandelion soothe the gut lining and provide nutrients for mucosal repair. They work beautifully alongside hemp, and fungi to calm inflammation and rebuild the gut wall.

How to Find Mushroom & Adaptogens for Dogs with Leaky Gut 

If you’re exploring natural options to support your dogs leaky gut, microbiome, and gut health, try searching for:

• mushrooms and adaptogens for dog leaky gut
• mushroom extract blend for dog leaky gut

Whether your dog is struggling with leaky gut, or just needs extra support for their gut microbiome, a well sourced combination of mushroom extracts and adaptogenic herbs can offer meaningful support, especially when grown on the right substrate, extracted properly, and formulated with digestive resilience in mind.

Healing Begins in the Gut

Most of the dogs I rescued arrived with leaky gut after years of kibble, meds, stress, and toxins have wrecked their microbiomes. But with the right approach and using whole food, mushrooms, adaptogens, and full-spectrum hemp helped every single one of them reach homeostasis in their gut. .

Healing begins in the gut. And when we heal the gut, everything else follows.

 

 

About Angela Ardolino

Angela Ardolino, a certified cannabis and fungi clinician, brings over 20 years of expertise to the field of holistic pet wellness. As a graduate of the inaugural Medical Cannabis for Therapeutic Use program at the University of Vermont School of Medicine, she is a passionate advocate for safe, natural, and ethically-grown whole plant and fungi medicine tailored for pets.

Committed to the highest standards, Angela continues to educate and inspire pet parents through her popular podcast, Your Natural Dog, where she hosts experts to discuss holistic pet care, natural remedies, nutrition, and training. Follow Angela Ardolino on Facebook, Instagram, TikTok, and YouTube to stay updated on her mission to educate and empower pet parents everywhere.