Gut Feeling: Calming Canine Anxiety with Microbiome Support

Nearly half of all U.S. households have a dog,1 and unfortunately, anxiety is a common issue among our furry companions. In a survey of over 13,000 dogs, 72.5% showed anxiety-like behaviors.2 These can include noise sensitivity, separation anxiety, aggression, and other challenges that not only impact a dog’s quality of life but are also a leading cause of shelter surrenders.

Traditionally, managing these behaviors has involved a mix of training and environmental changes. But emerging research is pointing to another, less obvious path: the gut—and the trillions of microbes living there.

The Canine Microbiome

With the advancements in next-generation sequencing, scientists can now better understand the plethora of microbes that live on (and in) our bodies. In recent studies, scientists gathered samples from various locations on our bodies to identify microbes based on their DNA. These studies have expanded to understanding the microbiomes of our environment and other beings that surround us. Our dogs weren’t an exception.

When scientists studied the microbiomes of entire households, they found something pretty amazing: family members share microbes—not just with each other, but with their dogs too.3 When researchers looked at the gut, they found that dogs and humans have similar microbiomes.4 And it goes beyond the gut—dog owners actually share more skin bacteria with their dogs than with other dogs. Diet plays a big role, too, and changing a dog’s diet can also modify the microbes within their gut.5 Dogs on raw food diets have distinctly different microbial communities than those eating commercial food.6 Even when dogs are fed the same diet, their breed can influence which microbes thrive in their gut.7

While these studies may seem like an accumulation of “fun facts” to impress dog lovers, they actually point to something quite significant: the dog’s microbiome is flexible, shaped by the environment, and can have significant impacts on a dog’s health. Like in humans, the state of a dog’s microbiome can impact many things ranging from digestive health to immune health, and even behavior.

Understanding the Gut-Brain Axis

One of the drivers behind how gut microbes impact behaviors is the gut-brain axis. The gut-brain axis refers to the bi-directional communication between the brain and the gut. Nervous about something? You might feel butterflies in your stomach. The same could be true for our furry friends. The gut and the brain “talk” by sending molecules between each other and through various pathways, including neuronal, hormonal, and immune signaling. These include short-chain fatty acids like butyrate and key neurotransmitters such as serotonin, dopamine, and GABA (gamma-aminobutyric acid). Microbes help produce these compounds, which can enter the bloodstream and affect mood and behavior. The vagus nerve—which links the gastrointestinal tract to the brain—also tells the brain about what’s going on inside the gut and vice versa. And when it comes to calming signals, GABA plays a crucial role.

GABA’s Role in Canine Calmness

GABA is an inhibitory neurotransmitter that has effects on reducing stress and anxiety. GABA helps calm the mind by relaxing the nervous system and dampening neuronal over-reactivity. In cases where the body doesn’t produce enough GABA, the neurons can react too quickly, creating an anxious effect. Research has found that medications that increase the amount of GABA have a relaxing, anti-anxiety effect in many organisms, including humans,8 dogs, and mice.9 When aging dogs ate food supplemented with GABA for two weeks, their emotional state and quality of live improved.10 In fact, a study of Shih Tzu dogs found that supplementing GABA orally changed their activity and decreased the levels of urinary cortisol, a hormone known as the “stress hormone.”11

Recognizing GABA’s calming effects on pets, many in the field have turned to GABA-focused supplements for dogs—either by delivering GABA directly or by using ingredients like L-theanine to help boost its levels naturally. These calming aids often come in the form of supplemental chews or are added into pet food. But there’s a catch: most provide a quick, one-time dose that wears off in a few hours, leading to the need for frequent re-dosing.

That’s why Verb Biotics has created GABA Pet (LP815™), an ingredient solution that supports a prolonged release of GABA, so that our dogs can really ‘feel the effect.’ We designed GABA Pet to provide GABA in two ways: orally, as well as enabling existing microbes in the canine gut microbiome to produce GABA from within. When we put GABA to the test in a 35-day trial involving 23 breeds of dogs, we saw significant reductions in aggressive and anxious behaviors and improvements in sleep.

While research on GABA supplementation in dogs is still evolving, it’s clear from existing studies that both the gut microbiome and GABA levels play a significant role in canine health. As we continue to explore this connection, more comprehensive studies will help us better understand how the microbiome influences a dog’s physical and emotional well-being.

About the Author: Jennifer Tsang, PhD is a microbiologist turned freelance science writer whose goal is to spark an interest in the life sciences. She works with life science companies, nonprofits, and academic institutions on anything from news stories, explainer articles, and content marketing. She shares the wonderful world of microbes on her blog The Microbial Menagerie. Learn more about Jennifer on her website jennifertsangwrites.com.

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