Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Are Dogs Mouths Cleaner Than Human Mouths? Vet Approved Facts & FAQ

Share

happy dog getting pet by owner

It’s commonly believed that dog mouths are cleaner than human mouths. However, this belief is simply a myth, and dog mouths aren’t any cleaner than human mouths. While there are some similarities between the two, there are just too many differences to make any fair comparisons. Some would say that it’s like comparing apples to oranges.

Since licking is a normal dog behavior, it’s worth understanding what’s going on inside your dog’s mouth. We’ll answer some common questions that many people have about dogs’ mouths and their oral hygiene.

divider dog paws 2 oct 2024

Comparing Dog Mouths and Human Mouths

While it may sound a bit gross, mouths are hosts to microbiomes and contain a diverse ecosystem of bacteria. Both human mouths and dog mouths contain billions of bacteria and can host roughly 700 unique species.1 Some species of bacteria found in the mouth of dogs are infectious to humans, but most are not.

There’s some overlap in the types of bacteria that are found in dog and human mouths. However, the majority of species found in a dog’s mouth are different from the species found in a human’s mouth. So, even though there are a few harmful bacteria that may occur in a dog’s mouth that would cause disease in a human e.g. Salmonella spp., most viruses and bacteria in a dog’s mouth can’t survive in a human host.

owner holding the jaw of west highland terrier puppy
Image By: LanKS, Shutterstock

Origins of This Myth

It’s unclear as to how the myth about dogs having clean mouths came to exist. However, it’s possible that it started with the observation that humans don’t seem to catch diseases when their dogs lick them. While it’s common knowledge that diseases can be transferred orally from human to human, some people don’t realize that we can also catch diseases from their dogs. Oral transfer of harmful bacteria from dogs to their owners is rare, but it can still happen.

Dogs also frequently lick their wounds. So, it’s possible that people believed their saliva had healing properties. In fact, certain ancient civilizations, including the Greeks and Egyptians, included the use of dog saliva in healing rituals and practices.

Dogster divider_v2_NEW_MAY_24_

Frequently Asked Questions (FAQ)

Now that we’ve cleared up this myth, we’ll answer some frequently asked questions that many dog owners have about their dog’s saliva and oral hygiene.

Does Dog Saliva Have Healing Properties?

Technically, dog saliva and human saliva both contain healing properties. Histatins are proteins found in saliva, and they can help protect wounds from infections and encourage open wounds to close faster. Another protein found in saliva that can help speed up wound healing is nerve growth factor. Saliva also contains nitrite, which works to break down nitric oxide to prevent infections.

Should I Let My Dog Lick His Wounds?

While dog saliva may contain healing properties, it’s still best to take your dog to your veterinarian if they’ve sustained an injury. Your veterinarian can assess the wound and determine the best way to care for it and let it heal.

Dogs can lick wounds for a variety of reasons. Licking can help clean up any dirt or debris around the wound. Dogs may also lick their wounds to soothe any itching or inflammation. However, it’s not always a good idea to let dogs lick cuts and scratches. Dog saliva does have some healing properties but it also contains many bacteria that can cause infections. So, they can risk exacerbating a wound and make it worse if they continue licking a wound.

vet putting on bandage to dog's leg
Image Credit: didesign021, Shutterstock

Can Infectious Diseases from a Dog’s Mouth Transfer to Humans?

Though the chances are low, dogs can still transfer infectious diseases when they lick a human. Since dogs and humans can host several of the same bacteria, dogs can cause humans to get sick if humans come in contact with their saliva.

One example of bacteria that can transfer from dogs to humans is Salmonella. Dogs that eat a raw food diet are at higher risk of ingesting contaminated meat. If they were to lick their owners after eating, the Salmonella bacteria could transfer to the humans, especially if the dog was licking their faces.

People have a higher risk of catching an infectious disease from dog saliva if the saliva enters their mouth or comes in contact with a cut or scratch on their skin. You can also catch an infectious disease from a dog bite. So, if anyone gets bitten by a dog, it’s important to clean the wound thoroughly and seek urgent medical attention.

Why Does My Skin React When My Dog Licks Me?

Some people will have an allergic reaction to dog saliva. Dog saliva contains certain proteins that can trigger a person’s allergies and cause their skin to develop a rash or break out in hives. Allergens can also be found in dog dander and urine.

Why Does My Dog’s Saliva Smell Bad?

A dog’s saliva can smell bad for a lot of reasons. Sometimes, it can simply be because they ate something stinky. However, smelly saliva and bad breath are usually indicators of an underlying health issue that requires veterinary care. For example, bad breath can be a sign of gum disease, kidney disease, or diabetes. Smelly saliva may also be caused by food or a foreign object getting lodged in your dog’s mouth.

close up of white dog opening its mouth
Image Credit: Alexas_Fotos, Pixabay

How Can I Keep My Dog’s Mouth Clean?

Dental disease is prevalent in dogs, and 80% of dogs over 3 years old have active dental disease. So, it’s important to establish a dental care routine as early as possible and be vigilant about keeping your dog’s mouth clean.

One of the most effective ways to keep your dog’s mouth clean is to brush their teeth daily. Most dogs won’t enjoy getting their teeth brushed at first and will require gradual training to get used to the feeling. It’s also best to try out different types of brushes to see which ones are most comfortable for your dog.

Dog mouthwashes and water additives are other dental products that you can add to your dog’s dental hygiene routine. They’re not as effective as toothbrushing, but they’re still good at freshening up your dog’s breath. Dental chews can also help keep plaque and tartar buildup at bay.

Lastly, make sure to stay on top of your dog’s routine physical exams. Your veterinarian can examine your dog’s teeth and recommend and perform dental cleanings, if necessary.

If you have any concerns about your dog or their health, we recommend you contact your vet directly.

If you need to speak with a vet but can't get to one, head over to PangoVet. It's our online service where you can talk to a vet online and get the advice you need for your dog — all at an affordable price!

PangoVet_Mention-in-Content Savings V1

divider dog paws 2 oct 2024

Conclusion

Dog mouths aren’t any cleaner than human mouths, and their saliva can have both positive and negative effects on wound healing.  So, it’s best to take your dog to your veterinarian if they sustain an injury and have an open wound. Your veterinarian can work to protect the wound and prevent it from getting infected.

You also can’t rely on your dog’s saliva to keep their mouth and teeth clean. Dogs require daily care to prevent dental disease. Making it a habit to brush your dog’s teeth and using other dental hygiene products can lower the risk of dental disease significantly and ensure your dog’s teeth stay healthier for longer.


Featured Image Credit: Bachkova Natalia, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything dog

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.




How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.


Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

DIY Repellents for the Dog Who Thinks Everywhere Is His Toilet

Dog urine and everything nice have a complicated relationship. One thrives, the other suffers, and if you’re reading this, you already know which...

Dogster’s Weekly Photo Contest Winners: I Dig, Therefore I Am (March 5, 2026)

Every week our team gets the privilege of sorting through our readers photos to choose what dogs will win this weeks contest! See...

Ways to Stop Dog Boredom Before It Destroys Your House

Your dog is staring at you. They’ve paced between the door and the couch. They’ve sighed dramatically from their bed. The message is...

Kennel Club Quietly Adds 14 Breeds to High Risk List

Earlier this month, the Royal Kennel Club in the UK sparked controversy when it quietly announced that, in addition to the Bulldog, French...

More related

Valley Bulldog: Info, Pictures, Facts, & Traits

Are you thinking of adding a dog to your home and considering the Valley Bulldog? If so, you’re in for a world of...

How to Live With Dogs When You Are Allergic: 8 Vet-Approved Tips

Achoo! No one likes sneezing, runny eyes, or itching! We love our pups but don’t always love that dander—it’s a real trigger. So,...

Chiweenie (Chihuahua & Dachshund Mix): Info, Pictures, Care & Traits

The Chiweenie is the perfect pooch for the person that wants to bring their dog everywhere they go. If you can’t stand to...

Bernedoodle (Bernese Mountain Dog & Poodle Mix): Info, Pictures, Care & More

The Bernedoodle is a cross between the intelligent Poodle and the gentle giant, the Bernese Mountain Dog. Owners say that the hybrid adopts...

Keep reading

Can Dogs Drink Milk? Vet Verified Nutrition Facts & FAQ

Many dogs are always looking to share whatever foods you happen to be eating at meal or snack time. Whether it’s a sandwich, a cupcake, or even a glass of milk, they always seem to be there to pick up...

Can Dogs Drink Milk

11 Best Dog Foods for Golden Retrievers in 2026 – Reviews & Top Picks

Golden Retrievers are one of the most beloved dogs in the United States. These friendly and lovable dogs can be prone to specific health conditions and diseases, so it’s important to make sure that they’re eating the right kinds of...

golden retriever dog eating healthy dry food from bowl at home

10 Best Dog Foods for Maltipoo Puppies in 2026 – Reviews & Top Picks 

You’ve just brought home an adorable Maltipoo puppy from the breeder, and you’re excited to watch this little ball of fluff grow into an adult. Puppies of all breeds need well-balanced nutrition to grow up strong and healthy, but not...

Maltipoo puppy eats from a metal bowl

Can Dogs Eat Carrots? Vet-Approved Nutrition Facts & FAQ

While we all love a tasty treat occasionally, we often wonder if the foods we’re snacking on are safe to offer dogs, especially when they look at us with those pleading puppy-dog eyes. If you are a carrot fan or...

Can Dogs Eat Carrots

What Time Should I Feed My Dog? Vet-Verified Feeding Guide

Canine nutrition can feel like an impossible labyrinth to navigate, whether you’re a first-time dog owner or not. There is so much information—and misinformation—out there, making it hard to know exactly what time of day to feed your dog and...

Schnauzer puppy dog eating tasty dry food from bowl

Can Dogs Have Olive Oil? Vet-Verified Health Facts & FAQ

You’ve undoubtedly heard of the benefits of olive oil on human cardiovascular health. Research has also shown it has anti-inflammatory properties, contains antioxidants, and may help protect against or treat a variety of conditions in people, including rheumatoid arthritis, cancer,...

olive oil

How Long Can a Dog Go Without Food? Vet-Verified Facts & FAQ

If your dog hasn’t been eating well, it’s normal to be concerned, and if it’s been a while since your companion seemed interested in food, you might be worried about how long it’s safe for a dog to go without...

sad golden retriever dog beside food bowl on the floor with no appetite

Freshpet Dog Food Review 2026: Recalls, Pros & Cons

Review Summary One of the first brands to promote fresh food for pets, Freshpet has been on the market since 2006. Freshpet is available at many pet food retailers and is instantly recognizable as the rolled food in the refrigerator....

Dogster_Freshpet Dog Food Review

Love Dogs? So Do We! Join the Dogster Community

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.




Sign up for the Dogster Email Newsletter