
You won’t have missed all the good-news stories about the effects of probiotics on gut health for humans and animals. If you’re taking probiotics, you’ve probably wondered if you can give them to your dog too. Let’s take a closer look at everything you need to know about dog probiotics vs. human probiotics, so you can make informed decisions and take the best care of your pup.
What Are Probiotics?
We humans have trillions of beneficial microbes living in our guts. And, just like us, dogs also have ‘good bacteria’—with health benefits influencing everything from their digestion to immune system function[1].
The recognized definition of probiotics is ‘live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.’[2] Probiotics give these health benefits by supplementing the beneficial bacteria and supporting the ‘friendly’ gut microbes.
Are Dog Probiotics The Same As Human Probiotics?
Human Vs. Dog Gut Microbes
A dog’s microbiome is made up of five predominant phyla (the technical term for groups of organisms with similar characteristics). These are Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, and Fusobacteria. The main types are Fusobacterium, Bacteroides, and Firmicutes [2,3], which are similar to the bacteria found in humans, but differ in their composition and strains[2,4].
Different bacteria can have different impacts on dogs and humans. Fusobacteria is one of the most abundant phyla in dogs, but in humans it can be associated with gut disease[2]. On the other hand, Clostridium difficle, which can cause severe illness in humans, is found in perfectly healthy dogs[2].
In both humans and dogs, the composition of gut microbes can be influenced by diet and health[2,3]. For example, meat-based diets increase the abundance of bile-tolerant microbes in humans, and decrease the levels of Firmicutes in both humans and dogs, while higher levels of vegetable fibers will increase Firmicutes and decrease levels of Fusobacteria and Proteobacteria in humans and dogs[2]. Gut microbiome composition can also be altered by obesity in dogs and humans alike[5,6].
Pet Probiotics Vs. Human Probiotics
Although there are similarities between human and dog gut microbes, it’s important to understand that there are differences in strains and composition between them, which can be the difference between bacteria being beneficial or harmful[2]. Also, very few human products have been clinically tested in dogs, so there are lots of unknowns.
Upset levels of gut microbes (known as ‘dysbiosis’) can trigger inflammation in the gut in both humans and animals[2,7].
Are Probiotics For Humans Safe For Dogs?
As human probiotics have not been safety-tested in dogs, it is recommended you ensure the probiotics you give your dog are approved for that species. Other important points to consider include:
Probiotic Composition
The amount and types of good bacteria may vary in human and dog probiotics to reflect the differences between the bacteria dogs and humans naturally have. While they may not be harmful, human products are not safety-tested for use in dogs. Furthermore, they may not offer any health benefits. It’s best to stick to a formulation specifically designed for use in dogs.
Additives
There is an endless number of human probiotic products on the market, so it’s hard to provide one-size-fits-all safety advice. While the strains of bacteria themselves are unlikely to cause a problem for your pup (or provide any benefits), the additives these products contain might. For example, there are some human sweeteners (such as xylitol, also known as ‘birch sugar’) that are highly toxic for dogs[8] and found in some probiotic products.
Natural Probiotics
Many human food products claim to have probiotic benefits, but pet parents need to remember their pups aren’t small humans. Caution should always be taken before giving human foods to dogs—probiotic or not—as they may be detrimental to your dog’s health. For example, some dogs are lactose-intolerant[9], so probiotic yogurt may upset their gut rather than help them.
What Makes A Good Probiotic For Dogs?
Given the uncertainty regarding the benefits of human probiotic products for dogs, you’re probably asking yourself: ‘How do I choose a probiotic for my dog?’
The best bet is to choose a product that’s aimed specifically at dogs. What do you need to look out for? Ideally, a dog probiotic that:
Contains microorganisms registered for use within that species
Lists the types of bacteria, down to individual strains
Provides a guarantee of the number of colonies (live bacteria) present at the end of the product’s shelf life
Is within the expiry date
Has evidence to back up its claims
Final Thoughts
While in most cases giving dogs human probiotics is unlikely to cause any harm, it may not give your dog any benefits either and is unlikely to have been safety-tested on dogs. Depending on the human probiotic product, there may also be sweeteners or additives that are harmful to your dog.
There may be specific times your veterinarian recommends a human probiotic, and they’ll be happy to discuss it with you based on your dog’s circumstances. Ultimately, as a pup parent looking to add a probiotic to your dog’s daily routine, it’s best to look for a product with proven benefits and designed with dogs in mind.
- Pilla and Suchodolski (2020) The Role of the Canine Gut Microbiome and Metabolome in Health and Gastrointestinal Disease. Frontiers in Veterinary Science. DOI https://doi.org/10.3389/fvets.2019.00498
- National Institute for Health (2023) Probiotics. Available at https://ods.od.nih.gov/factsheets/Probiotics-HealthProfessional/
- Coelho et al. (2018) Similarity of the dog and human gut microbes in gene content and response to diet. Microbiome. DOI https://doi.org/10.1186/s40168-018-0450-3
- Vazquex-Baez et al. (2016) Dog and human inflammatory bowel disease rely on overlapping yet distinct dysbiosis networks. Nature Microbiology, DOI https://doi.org/10.1038/nmicrobiol.2016.177
- Chun et al. (2020) Difference of gut microbiota composition based on the body condition scores in dogs. Journal of Animal Science and Technology. DOI 10.5187/jast.2020.62.2.239
- Geng et al. (2022) The links between gut microbiota and obesity and obesity-related diseases. Biomedicine and Pharmacotherapy. DOI https://doi.org/10.1016/j.biopha.2022.112678
- Zeng et al. (2017) Mechanisms of inflammation-driven bacterial dysbiosis in the gut. Mucosal immunology. DOI 10.1038/mi.2016.75
- Gwaltney-Brant (2022) MSD Veterinary Manual: Xylitol Toxicosis in Dogs, Available at https://www.msdvetmanual.com/toxicology/food-hazards/xylitol-toxicosis-in-dogs
- Craig (2018) Food intolerance in dogs and cats. Journal of Small Animal Practice. DOI https://doi.org/10.1111/jsap.12959
