Superb Dog
is dog saliva clean

Is Dog Saliva Clean? Are Dogs’ Mouths Cleaner Than Humans’?

You’ve probably heard it said at least once — “A dog’s mouth is cleaner than a human’s mouth!” We look at whether it’s true or not.

We all know how difficult it can be to resist some sloppy smooches from our furry pals. And when we do get those occasional licks on the face by our dogs, we usually don’t mind it because lots of people share kisses with their dogs and there’s probably no risk from contact with dog saliva, right? 


Well, that is the question — is dog saliva clean, and are dogs’ mouths cleaner than humans’ mouths? 

There is no scientific proof showing that dog saliva can be considered “clean” as it contains bacteria and microbes. The bacteria in dogs’ mouths are quite different from those found in people’s mouths, so comparing the two isn’t practical. And while dogs’ mouths are not any “cleaner” than humans’, they don’t generally pose any significant health risks to humans.

If you are interested in your dog’s hygiene and level of cleanliness, then you have come to the right place. We will explore the differences between dogs’ and humans’ mouths, and to what extent you can share things with your dog. In addition, we will clear up the many myths surrounding dog saliva and whether dogs’ mouths are cleaner than people’s mouths.

Is Dog Saliva Clean? 

If you are a person who shows love to their dogs with kisses, you are not alone — showing affection to dogs with facial nuzzling and kisses is common. However, people usually don’t this about the possible consequences of this exchange of affection. The saliva of most animals, including dogs, contains bacteria that can impact human health in different ways. 

There is a big difference between the saliva of dogs and the saliva of people. The properties that dog saliva contains help the dog differently, but they do not help people; you should not view dogs’ and humans’ immune systems as comparable. 

For instance, the bacteria in dog saliva is good for preventing dental cavities. That is why dogs rarely develop any form of dental cavities inside their mouths. However, this does not mean that dog saliva will have the same effect on your mouth if you exchange kisses with your dog.

There is also the myth that bacteria somehow cannot be transferred from dogs to human’s mouths. This is not true. Studies have proven that the bacteria found in dog saliva can definitely be transmitted to people’s mouths. If you exchange kisses with your dog often, then it is likely that at some point you have transferred their bacteria into your mouth. 

Dog Saliva Causing Allergies in People

Dog saliva can cause allergies in humans, although people almost always attribute these allergies to the dog’s fur and dander. According to a study, dog saliva contains 12 different protein bands that might cause allergies in people. So there’s actually a greater possibility that a person is allergic to dog saliva than dog fur. 

Is Dog Saliva Good For Your Skin? 

In general, dog saliva is harmless to the human body. Therefore, a sloppy lick or exchange of some affection with your dog will generally not affect your skin. However, because it does contain bacteria, people with highly sensitive skin might notice some irritation. It can also lead to infections if there are any breaks in the human’s skin barrier. 

While dog saliva doesn’t present any serious risk to your skin, it likely won’t help it, either. The idea that dog saliva can provide some sort of skin benefits has no scientific support.

Does Dog Saliva Cause Acne or Pimples?

Dog slobber does not cause acne or pimples. Acne is generally caused by excess oil or inflammation. Ingrown hairs can also contribute. Dog saliva does not cause acne.

High levels of emotional stress and lack of proper hygiene are common contributors to the conditions that cause acne and pimples. Sometimes, when people are stressed and they seek comfort from their dog in the form of kisses, they incorrectly identify the dog saliva transferred as the cause of the acne. This is a case of correlation, not causation.

dog licking man's face with saliva

Can Dog Saliva Heal Wounds?

Another popular belief is that dog saliva can help heal wounds. The thinking is that some component of dog saliva has healing properties because dogs lick their wounds and they usually heal.

Most animals lick their wounds. This can help keep the wound cleaner, which lowers the risk of infection and therefore promotes healing. It can also irritate the wound and make it worse (think hot spots that dogs create through excessive licking and chewing on small wounds).

Research has shown that saliva does contain histatins, which are proteins that do contribute to preventing infection, as well as other chemical compounds that do the same. So the claim is not unfounded at all.

It usually makes sense to allow a dog to tend to its wounds unless they become overly-attentive and lick the wound to the point that they are inflaming or irritating it. Also, if you have applied any medication such as a topical antibiotic, you don’t want your dog to lick that medication off of the wound as it will no longer be effective.

Should I Let My Dog Lick an Infected Wound of Mine?

So, if dog saliva helps ward off infection and speed of healing in dog wounds, does it stand to reason that having them lick a human wound will do the same?

While there is a chance that the above-mentioned properties of dog saliva could possibly provide benefits to a human wound, there are far more reasons not to let your dog lick a wound.

If you have an open wound that is infected, you should see a doctor. Properly prescribed antibiotics will be far more effective than dog saliva. Infection in the human body is a very serious matter, and the real threat is when the infection spreads into the body from the local wound.

Dog saliva might only help on a minor local wound and only if the type of bacteria it is effective against is present; it certainly isn’t going to help with an infection that has spread through the body. When dogs get wounds and infections, vets treat them with antibiotics, not dog saliva, and you should have a doctor do the same for your self.

In addition, there are many bacteria that exist in dog saliva that could potentially cause infection, which is yet another good reason not to let a dog lick a human wound.

Can Dog Saliva Cause Infection in Humans?

While dog saliva will usually not cause serious issues if it comes in contact with human skin, it can cause serious infection if it breaks the skin barrier and bacteria enters the body. 

This often occurs when a dog bites a person. Bacteria from the dog’s saliva enters immediately at the wound site. Doctors will almost always prescribe an antibiotic to dog bite victims to prevent infection from developing.

Human saliva, however, poses the same risks to other humans. A common situation where this occurs is when someone punches another person in the mouth with a clenched fist. Known as a “fight bite,” the bacteria from the saliva of the person being punched enters into the wound created on the knuckles of the puncher. Infection may then develop as a result.

So even though certain bacterias are considered “clean” enough to live in a species mouth, they can be dangerous if they enter other parts of the body.

Is Dog Saliva Cleaner Than Human Saliva? 

You have probably heard the popular claim that dog saliva is cleaner than human saliva, and wondered whether it is true. This is not at all true. 

First, it is wrong to compare dog saliva to human saliva. This is because dogs have different microbes in their mouths that do not exist in human mouths. Dogs’ bodies operate differently from humans’, and we do not share the same bacteria and microbes as dogs. 

While dog saliva can help dogs with different dental processes or digestive issues, it does not mean that that same saliva can perform the same functions for people. Dogs and humans have very different physiologies and health needs.

Obviously, human saliva is clean enough for humans’ mouths, and dog saliva is clean enough for dogs’ mouths.

Are Dogs’ Mouths Cleaner Than Humans’?

Once again, a dog’s mouth and a human’s mouth cannot be compared. According to  research professor Colin Harvey, it’s like comparing apples and oranges. This is because even though both dogs’ and humans’ mouths are full of microbes and bacteria, the makeup of these germs is very different for each.

While some bacteria might be the same in both humans and dogs, there are microbes that are found in dogs but not in people. For example, dog mouths contain bacteria that can cause periodontal diseases — making the mouth technically “not clean.” But human mouths contain different bacteria that also can cause periodontal disease. Is one mouth “cleaner” than the other when they both contain unique bacteria capable of causing disease?

Simply put, it cannot be said that dogs’ mouths are cleaner than humans’ mouths. Considering the fact that dogs, as well as humans, are carriers of different types of bacteria and microbes that cannot be measured against each other quantifiably, such a claim is silly to try to make.

Also, one needs to consider oral hygiene in this case. Both humans and dogs need proper oral hygiene to keep the mouth healthy. Humans brush and floss daily (well at least some do!), while dogs depend on chew toys and bones to keep their clean.

dog saliva drooling out of dog's mouth

Conscientious dog owners brush their dogs’ teeth and encourage play with toys that promote dental health. Although you can start this at any stage of a dog’s life, it is much easier if you begin oral hygiene when your pet is still a puppy. That way, they can get used to the habit of being handled around the mouth, and your job will end up being easier in the long run.

You can always consult with your vet about the proper tools and techniques for oral hygiene for dogs. There are a many toothbrushes and toys designed for dogs and for their oral hygiene needs. This does not mean that your dog’s mouth will be cleaner than yours, but it will be healthier than if you neglect its care. 

Is A Dog’s Mouth Cleaner Than A Toilet? 

This is another question that seems to get asked often in reference to the relative cleanliness of a dog’s mouth. If you keep good oral hygiene of your dog’s mouth and teeth, then yes, it would likely be “cleaner” than a toilet.

However, again, we are discussing different kinds of bacteria, so it cannot be certainly stated that a dog’s mouth is cleaner than a toilet. Perhaps if your dog drinks from your toilet, you will have a definitive answer. 

Final Thoughts

Although different species can share similar bodily processes and parts, each species has its own physiology and functions. While both humans and dogs produce saliva in their mouths, the makeup of that saliva is different for each species. Each serves its own species in a specific manner. Therefore, it’s impossible to compare the two and determine which one is “cleaner” or “better.”

A dog’s saliva is “clean” for a dog, and human saliva is “clean” for humans. But both contain bacteria and microbes that are probably best avoided by the other species.

So when sharing affection with your dog, you may want to play it safe and limit the amount of saliva exchanged. Their saliva might not be harmful if you occasionally contact it, but it still has the potential to be infectious, so it is better to minimize that risk. 

If you’re ever in doubt about whether a dog’s saliva is clean or not, just think about the times you’ve seen dogs eating trash, cat stools, or dead birds or other animals and your question might be answered.

Superb Dog Editor

Superb Dog Editor