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A reader writes: "I have a problem with people who say 'a dog's mouth is cleaner than a human's.' I have asked for facts from these people to back up their statements but no one has been able to provide them to me. I believe that dogs and humans have similar enzymes for breaking down food, and I know that my dog licks herself in places I don't, and she always has 'doggie breath.' I don't think it's possible for a dog's mouth to be cleaner, unless dogs have some super-secret enzyme that we don't."  Read the answer...


June 1, 2006 at 9:17 am
(1) Melissa says:

i do think dog mouths are cleaner!!!

March 20, 2011 at 7:55 am
(2) john says:

same. humans are dirty as

October 16, 2011 at 12:58 pm
(3) Erick says:

that is so true Melissa!

December 17, 2006 at 12:07 pm
(4) Leigh says:

Well, I still think a dogs mouth is cleaner, because my dog licks my face all the time!!

April 21, 2011 at 7:53 pm
(5) Randal Coon says:

So sorry that you SUFFER under this misconception. My goats also put their tongues a lot of places where I don’t and I have never heard them referred to their mouths as cleaner, except in language only.

December 26, 2006 at 4:28 pm
(6) Doug says:

A dog will lick anybodys face, but not everybody will kiss yours, especially if it smells like dog.

January 8, 2007 at 12:43 pm
(7) Micah says:

If you ever watch ( MYTH BUSTERS ) on cable. They did an segment where they just happen to test that theory, where one of the guys swabed there mouth and ran the swab over a petriey dish and then swabed a dogs mouth and did the same. They put the two samples in an incubator cabinent and guess which one had more bacteria growth. The human culture had more bacteria growing in it than the culture from the dog LOL so if you let your dog kiss you. Who knows what you could be giving your dog since your mouth is more infected with bacteria than your dogs…..

November 4, 2011 at 3:13 pm
(8) Meh says:

I refuse to believe you simply because you aren’t smart enough to write at a 5th grade level.

January 16, 2007 at 7:45 pm
(9) john says:

A dogs mouth is not cleaner than a humans because they get into trash and meat and stuff.

January 30, 2007 at 5:22 pm
(10) spook says:

After reading the comments to this article, I couldn’t but laugh at the last one from John. Humans eat meat and “stuff” too. As to getting into trash…what is the trash made up of?? Food that humans have eaten some of and then throw the rest away. Please read the comment from Micah. The episode that he is talking about is a great one!

February 1, 2007 at 11:21 am
(11) TAD says:

You people who let your dog,or any animal for that matter,are sick. Dogs not only lick themselves in all the wrong places IE BUTT, they also eat POOP. We all know this to be true. So I say would you kiss someone who just ate poop. would you eat poop at the dinner table?

February 22, 2007 at 2:47 pm
(12) Genesis says:

i personaly think that dogs have cleaner mouths then humans do. i have two dogs of my own and i have let my dogs kiss me and even lick my tongue. some people might think that i am gross but its honestly not that bad. i mean you french kiss people but do you know were there mouths have been before you kissed them?

March 5, 2007 at 10:37 pm
(13) bri says:

a dog mouth because dogs do bot eat or drink as much lidquids as we do. dog do not swap spit like humans do. i think a humans mouth has more bacteria because they can have tooth decay or have pther thing we do not know about………

March 9, 2007 at 12:13 am
(14) Marci says:

Not all dogs get into garbage. Most dogs are house dogs which means that they eat dog food or canned food, either way what humans eat is no better than what they eat. I think that dogs mouths are cleaner!

March 17, 2007 at 11:17 am
(15) Joe says:

I recently did an experiment in Microbiology class. The people had ~500,000 bacteria/swab, and the dogs had ~6,600,000. You draw your own conclusion.

April 11, 2007 at 10:03 pm
(16) kenneth says:

um well i ave learned that dogs mouth are cleaner than humans cause they well i dont know but do some research and find out !! but if you would have wnet schol enought is siad dog mouths were cleaner duh you doedoe

May 19, 2011 at 3:29 pm
(17) kieran says:

did you go to “schol” haha

October 15, 2011 at 12:12 am
(18) lolololol says:


April 15, 2007 at 7:03 pm
(19) Kaylee says:

i am doing a research project on “who’s mouth is cleaner a humans or a dogs”. and i’ve done alot of research and most websites state that a dogs mouth is cleaner.Though they lick themselves and get into the garbage they may have something in their mouths that we dont know about!

April 18, 2007 at 4:56 pm
(20) cory says:

it is true…..dogs mouth is cleaner than humans, just watch MYTHBUSTERS

April 20, 2007 at 5:29 pm
(21) sabrina says:

a humans mouth is cleaner that is what i think

April 27, 2007 at 6:02 pm
(22) cory says:

I think a dogs mouth is cleaner

May 1, 2007 at 1:48 pm
(23) Sophie says:

I’m am doing a project on this subject and right now the human is having the most bacteria, my little brother! I also did it with my yorkie Chewie, my cat Emotep (greek name) and it was very easy to tell.

May 1, 2007 at 4:42 pm
(24) mike says:

a dogs mouth regenerates every 7 seconds

May 7, 2007 at 10:52 pm
(25) Baby Jesus says:

Just to clarify things, when talking about humans, are we talking about males or females or just humans in general? Because I happen to think that women have dirty dirty mouths, especially the innocent ones. Therefore, I think that dog’s mouths are cleaner than women but not as clean as a man’s. Capisci?

May 11, 2007 at 4:14 pm
(26) Tommy says:

What ever. I don’t know about you but… I use a wash cloth to clean my privates. Dogs, not having thumbs, tend to lick themselves. Sounds like a good way to get a2s mouth.

May 31, 2007 at 4:22 pm
(27) david says:

dogs mouths can be cleaner then humans and somtimes not thats why they doggie breath mints and doggie dentist treats and bones

May 31, 2007 at 4:24 pm
(28) david says:

opps i meant makes

June 1, 2007 at 10:11 pm
(29) Jacki says:

The guy who said do you eat poop for dinner just made my night…that was hilarious…good stuff

I do however let my new little Pug kiss me all the time :)

June 1, 2007 at 10:13 pm
(30) Jacki says:

Oh and babies and kids put weird s*** in their mouth too…would you not kiss your own??

And props to the person who made the point ie you don’t know where a person’s mouth has been either. As a social worker I’ve heard of some pretty sick things

June 9, 2007 at 9:19 pm
(31) trey says:

a dogs mounth is cleaner than a humans mounth yal buggin check animal plant.xom it is wat is

July 8, 2007 at 8:07 pm
(32) Tiffany says:

You guys are funny really. First off not ALL dogs eat trash nor eat poop. My dog doesn’t eat trash nor does he eat poop. Second of all Dogs mouths may be a bit cleaner then ours but just because it is a little bit doesn’t mean a whole lot. Oh and most germs they have are only dangerous to other dogs keep the shots up though. You would get sick from another human faster than a dog.

July 21, 2007 at 10:52 am
(33) andrew says:

you are stupid saying that

July 29, 2007 at 8:50 am
(34) Liz says:

Well, My friendīs dog licks her icecream all the time. And Almost every person in the world lets their dog kiss them. So I believe that dogīs mouth is a bit cleaner.

Also, You donīt lick or drink off of someone elseīs plate or cup thats not related to you, but you let dogs do that. I think you do get sick more/faster from humans than dogs.

August 2, 2007 at 11:23 am
(35) jodimmples says:

no one has ever had a fungus from kissing a dog but u can sertantly get a fungus kissing a human. dogs are cleaner.

August 7, 2007 at 8:40 am
(36) Roger says:

What makes a dogs mouth clean is not what they eat or lick. It’s the fact that there mouth’s are cooler so many germs and bacteria can’t survive in a dog’s mouth that can in a human’s. Many people stick things in there mouth every day that are far worst then trash or genitals. For instance ever put a pen in your mouth do you know how many people don’t wash there hand after they go the bathroom. Even worse how about touch a keyboard and then don’t wash your hands before you touch your food. How many times have you shaken someone hand before you sat down to lunch. How many times have you kissed your spouse and it’s been hours since she brushed her teeth so all the germs and bacteria from the tempature of her mouth are just being passed right on to you. So even then the bacteria and germs can’t survive on a dog’s tongue like they can your’s. You can believe as you will but fact remains Dog’s mouth is cleaner then your’s.

August 19, 2007 at 8:38 am
(37) charliedog says:

OK—NOBODY has brought up a very obvious fact about humans that is just as disgusting as dogs licking themselves. think about where most every man’s mouth has been when giving oral to his girlfriend (I’m not trying to be pronographic here, just making an obvious point). What about you ladies? Where has your mouth been on those romantic bedtime nights w/ your man? Not to mention some of the “crap” we humans eat. Snails (escargot), Fois Gras (gooose vomit basically), chitlins (which are pig or beef intestines) found in dishes like menuto and others in the southern US. I could go on and on about how hipocritical it is of us to think that our mouths are SO pure and good. Maybe dogs breath is no better but other than my wife—I’ll kiss a dog any day over a human. HEY, have you ever noticed dogs never have morning breath? Very telling! Now next time you kiss your significant other, remeber where that mouth has been

August 29, 2007 at 7:50 pm
(38) Cosminc says:

I just want to know how often do dogs brush their teeth ? I know I do everyday as well as floss and use mouthwash. I also did notice that my dog has a lot of plaque between his teeth and offered him some floss but he didn’t used it =). I think I will keep away from a tounge that licks its own a$$

December 10, 2007 at 4:20 pm
(39) Gabe says:

Im doing an experiment on that for school but i think that certain dogs mouths are cleaner

December 11, 2007 at 6:39 pm
(40) Rixter says:

Dear Roger, I believe firmly that you are correct on the matter. Im not solicting that person has to kiss their dogs, thats not the point here. The question is, is a humans or a dogs mouth cleaner. The answer is obvious. The end of the story.

January 8, 2008 at 6:36 pm
(41) Leigha says:

look im younger than all yal and i know b/c i personally have tested, that a dogs mouth is cleaner that a humans. and no if you have a disease it cant be passed to a dog, why? they are mostly immune to all the diseases we get. but that doest mean we cant get what they have..

January 17, 2008 at 4:11 pm
(42) DEZZ says:

I made survey and went around my class and most of them say that a human’s mouth is dirtier. I personally thing the same. I mean, what if someone bites their nails. If you knew where their fingers were, would you kiss ‘em?? What if they don’t ever wash their hands!?

January 23, 2008 at 8:22 pm
(43) Girl From Alaska says:

i think dogs mouths are cleaner because they never get cold sores. We have more bacteria then the dogs which causes us to have cold sores

January 31, 2008 at 4:24 pm
(44) kkkkkaat says:

I still will always think that a dog’s mouth will always be cleaner then a humans

February 25, 2008 at 10:18 am
(45) kyle says:

thats my science project

March 4, 2008 at 8:51 pm
(46) Tarn says:

A humans mouth is cleaner!!!!!

April 20, 2008 at 6:47 pm
(47) Sun says:

Yes it is

June 10, 2008 at 6:58 pm
(48) carleigh says:

i believe dogs mouth are cleaner

July 8, 2008 at 1:32 pm
(49) shanna says:

a dogs mouth is not cleaner they lick their butts eat their puke if you think that a dogs mouth is cleaner u have mental problems

July 12, 2008 at 1:08 pm
(50) anonymous says:

According to ABC News, this is basically an urban legend. However, unlike the one about the psycho killer with the hook, this story has a grain of truth. Although the mouth of a typical dog is full of bacteria, it’s “species specific.” So, if a dog were to lick a person, most of the germs wouldn’t transfer. “Bottom line — you’re more likely to get a serious illness from kissing a person than kissing a dog.”

July 29, 2008 at 5:55 pm
(51) Deedee says:

Most of the comments I have read are based on a persons opionion,and not fact even if a dog has less bacteria and you can’t catch most
germs from a dog or other animals you can catch some things,ring worm,rabies,and the list goes on.some infections are caused by animals.Humans! well most of them brush and gargle at least 2 times aday and still have bacteria so what does that say for dogs.
If you want to let your dog kiss you in the
mouth that is your right, but personally I
would never kiss someone i knew did that i don’t care how much they brush.and from some things people do with their mouths kissing a
dog is no different.If you were in a restaraunt and knew your waiter did not wash there hands after using the bathroom .you probably would not catch anything but would you eat it.Urine from a healthy kidney is stearile just ask your Doctor,but I still would not want to eat something they have handled.I love animals but they are still animals.

July 29, 2008 at 6:09 pm
(52) Deedee says:

ps, If you really want to know ask your vet.

August 8, 2008 at 4:08 pm
(53) thomas says:

i think dogs mouths are cleaner because they have a warmer body tempeture than humans.i was told bacteria cant stay in warmer areas.

August 14, 2008 at 7:59 pm
(54) Paige says:

I was just talking to my mom and my friend about this and how i said that a dogs mouth could not be claner than a humans because they lick themselves in the crotch and the feet, they eat garbage and they have smelly breath. My mom told me to come onto google and search it so this is what i did…

August 28, 2008 at 8:31 pm
(55) Robert says:


or try:


Mythbusters?!? You have got to be kidding me!? How many samples did they use? How many subjects did they have? They screwed it up.

It is a fact that the AVERAGE human’s mouth is cleaner then the AVERAGE dog’s mouth.

Again this is fact. Just like the fact that grass is green, and the sky is blue, and the world is full of morons who let ‘thinking’ get in the way of fact.

September 19, 2011 at 7:56 am
(56) Vince says:

You are right!! And Mythbusters is for dumb people lol Also dogs teeth do rot. No dogs mouth is cleaner then mine. People only say its cleaner because they want a good reason to let them lick inside their mouths.

September 17, 2008 at 10:51 pm
(57) Tallos says:

Thank you Robert. Itís about time someone was intelligent about this. Thatís the problem with blogs, theyíre full of statements that are opinions or people relaying what they have heard. No facts. Come on people, look it up. Learn the facts yourself before making the comments. Thatís what the web is great for. Use it!! One person actually said that bacteria cant grow where itís warm. Are we serious? People really need to be better educated. And could we learn how to spell and punctuate people?

As a side note, I did like the regeneration statement. Made me laugh.

September 19, 2008 at 11:30 am
(58) Daesha says:

I know for a fact that a dogs mouth is not cleaner than an humans mouth!!!!!!!!!!!!!!!!

September 19, 2008 at 11:32 am
(59) Payton Coleman says:

aint no dogs mouth cleaner than no humans mouth

September 25, 2008 at 9:44 am
(60) Linda & Angela Say... says:

I ( Linda ) says YEAH dog’s mouths are definatly NOT CLEANER, cause they eat S***!
She ( Angela ) says, How you gonna ask a question when you don’t even know the answer…??????????????????????????????

September 25, 2008 at 10:58 pm
(61) EZ B says:

This is pretty simple. I have 2 dogs. One of them has some doggy breath, it’s not terrible, and the other dogs breath has no smell whatsoever. Neither of my dogs has ever brushed their teeth or gargled mouthwash at anytime of their lives. One of my dogs is 8 years old and the other is 6 1/2 years old. Let me repeat…..they have never brushed their teeth or gargled mouthwash in their lives.

Now take a human. If a human doesn’t ever brush it’s teeth or gargle any mouthwash in their lives……Imagine what would wreak from that person. I wouldn’t want to be a victim of it. There are people who have bad breath “just because”. Some people are born with it. I’m talking Halitosis(not sure if spelling is correct).

The typical human will go to sleep and wake-up with God awful “morning breath”…..that can’t be clean. If it “stinks” it can’t be clean. Imagine a human that never brushed it’s teeth in it’s life…..yuck..

Now to the argument about dogs licking themselves. I won’t say that dogs have clean “stuff”.

September 26, 2008 at 5:31 pm
(62) Akgirl says:

Dogs don’t brush their teeth, they eat trash and have nasty breath… People are nasty for letting their dogs lick their face/mouth after licking their butts. WHo knows if your dogs annal glans need drained and they are licking that into your mouth. Would you eat their crap too? Keep that tooth brush close!

September 26, 2008 at 5:46 pm
(63) Whatever says:

I beleive they have a lot more bacteria killing enzymes. I watched the man who lived with wolves and if he got a cut he let the wolves lick the wound to help it heal. He claims that it heals faster.

October 6, 2008 at 1:46 pm
(64) danny says:

ya’ll are stupid

October 15, 2008 at 2:55 pm
(65) Jim says:

My 6th grader just did this for his science project. He swabbed 3 humans (middle of the day), 3 humans (after brushing), 3 dogs and 1 cat and put them in a nutient blood agar petri dish. While this won’t tell you what type of bacteria a mouth has, it did show how many bacteria colonies grew in a 1 week period. The 3 humans (middle of day) had just 2-5 bacteria colonies. 3 humans (after brushing) had 2-20 bacteria colonies. We attributed this to the toothbrushes being contaminated and transfering into your mouth so remember to change your tooth brush regularly or sterilize it once in a while somehow. Out of the 3 dogs, ones mouth was as clean as a humans with only 2 colonies, the other two dogs had dozens of colonies and were really gross. The 1 cat we tested only had 1 colony growing. So from this test, while some dogs mouths may be as clean as a humans, some dogs mouths are really disgusting.

October 22, 2008 at 1:31 pm
(66) Mandi says:

i think a dog’s mouth is cleaner

November 13, 2008 at 1:20 pm
(67) alesha says:

ok no no no dogs lick their freakin crotch ok!?!?!

November 13, 2008 at 5:01 pm
(68) Smart Guy says:

Moat of you people can’t talk or spell worth a damn. If you are going to try and comment about something then you need to learn proper grammar and how to spell. Otherwise it makes you all look like fools. Don’t be an idiot when you’re on these forums. If you don’t have an education you shouldn’t be messing around on a computer in the first place. Go back to school and tell them that they failed because you are retarded.

November 17, 2008 at 12:47 pm
(69) Daesha says:

I have found out for a fact that a do9ds mouth is infact not cleaner tana humans!!!

December 11, 2008 at 12:16 pm
(70) ryan says:

So if a human’s mouth is cleaner than a dogs, why do you have to take action to avoid infection after receiving a human bite? As far as common household bites go, a cat bite is the worst, then human, then dog. Dog’s produce a bacteria killing enzyme in their mouth which humans are lacking.

December 16, 2008 at 10:35 am
(71) summer says:

ok lets say this if you r the IDIOT that says that a dogs mouth is cleaner you made the #1 spot on the stupid list of a world record.
O and mandi you stoopid

December 21, 2008 at 1:32 am
(72) bob says:

This article is correct. All dogs mouth’s are filthy. There is not such thing as a “clean” dog’s mouth. It is amazing to see the comments here which continue to believe that dogs have cleaner mouths than humans, despite all the evidence to the contrary. It is sad and pathetic that a person’s thinking could become so skewed.

December 21, 2008 at 10:18 pm
(73) alex Beck says:

dogs mouths is prolly cleaner but right after they lick their butts and stuff its prolly dirtier than humans.

January 1, 2009 at 10:45 pm
(74) eboni says:

i think that human mouth is cleaner than a dog because human brush there teeth every day and go to the dentitst thats what i think

January 12, 2009 at 3:47 pm
(75) Evie says:

Me and my two friends are doing a science fair projct on it and we are swabing 3 dogs and 3 humans mouthes and seeing whose are cleaner. Ill get back to you asap

January 15, 2009 at 11:47 am
(76) scott says:

same here im doin it for science fair too. ill come back to this later to see what evie says

January 21, 2009 at 11:41 am
(77) fred says:


January 31, 2009 at 9:55 pm
(78) Kevin says:

I have read through all of these posts and I think that a case has been made for both sides. Each side even alleges that they have “proof” to back it up.
What is escaping everyone so far is….Why?
Why in the world are people kissing dogs? (I do believe there were admissions of tongue as well)
What other animals are having their owners (that is what we are, owners) slipping them the tongue? Has society really fallen apart to this point, we cannot please or be pleased enough by a human partner that we have to kiss our dogs aka manís best friend.
I was here to find proof that is not a good idea for my sister to let her dog lick her toddlers face, then I read this and am even more concerned.

March 3, 2009 at 7:15 pm
(79) Hannah says:

Hi I am Hannah I am only 9 years old.A lot of people at my school ask me if dogs have cleaner mouths than humans.And I think they do.I know that is weard but I think they have cleaner mouths than we do.Because I have 3 dogs and they give me lots of kisses on my face.However,I have never got sick~! ;-)

March 3, 2009 at 7:44 pm
(80) steph says:

Hannah remember mom’s dog bite? Mom almost lost her leg!!!!!!!!! Guess what? I have NEVER BEEN BIT BY A HUMAN THANK GOD!!!!!!! Keep up on your reasearch my smart girl!I LOVE U!!!!!!!!!!

March 11, 2009 at 12:16 pm
(81) taylor says:

I really think Human mouths are cleaner than dogs.
Because we brush our teeth (hopefully) and Dogs… Use their tongues to clean themselves or other dogs’. I know you guys already discussed this, but really- Human mouths are way more sanitary.
Would you want your dog kissing you after gnawing on it’s anus?
I mean, doesn’t the… feces get stuck inbetween their teeth?
And with Humans, you know that… A majority of us isn’t entirely that disgusting!

March 27, 2009 at 9:24 pm
(82) Kelly says:

A dogs mouth is cleaner then a human, Even though we brush our teeth, dogs usually eat hard dry food which is a protection to diseases like gum disease, plaqe. When you see older dogs their teeth are yellow at the bottom, that is usual. An person at the age 75-90 lose teeth or have problems.

2. When you don’t brush your teeth and eat alot of candy cavities appear that is because acids eat your teeth. I hope that helped you alot bye

April 4, 2009 at 10:57 pm
(83) Sofia says:

It’s obvious that a dog’s mouth is cleaner than a human’s.
Dogs never brush their teeth, and their breath isn’t always so bad.
When you wake up in the morning, your breath is pretty bad before you brush your teeth, right? Well think about never brushing your teeth in your whole life. That would WAY worse than a normal dog’s mouth.
So it’s stupid how some people still think a human’s mouth is cleaner.

April 7, 2009 at 8:07 pm
(84) billy says:

dogs mouths are cleaner…..dahh

April 13, 2009 at 1:20 pm
(85) nathan channell says:

I think dog mouths are cleaner I know they lick in odd spots but thers is a way that dogs mouths are cleaner than ares even know my dog has ate is own crap he still has a cleaner mouth.

April 19, 2009 at 2:52 pm
(86) jeanne says:

Yes i think dog mouth are cleaner then humans cause dogs everyday they are licking people and for sure people would stop if they new that dog mouth are dirty but the fact is that dog mouth are cleaner then human.

April 29, 2009 at 3:08 pm
(87) dale says:

i dont think dogs mothes are cleaner than humas they have bad breaths and there mouth stinks they eat there own crap?

April 30, 2009 at 8:50 pm
(88) davonte says:

a dogs mouth is not cleaner than a humans because most owners let their dogs eat whatever they want to eat and don’t try to keep the dogs mouth clean and most dogs just eat right out of the trash if they don’t want to eat they’re own food.

May 6, 2009 at 9:06 pm
(89) Seriously says:

1. The term “cleaner” and less bacteria should not used to mean the same thing. Bacteria are everywhere and some prevent overgrowth of “bad” bacteria (you need specific bacteria in specific places). I would suspect that since dog’s lick and eat poop that they have coliform bacteria (poo bacteria) that is a marker for other bateria, parasites, etc that tend to make us sick.
2. What is used to grow the bacteria makes a difference because it selects for certain bacteria(i.e. blood agar, etc)
3. Dog’s teeth are a little further apart and less likely to have food jammed between them thus I suspect the reason they don’t need as much dental care (that and they only live 10-15years)
4. Most dog bites results in infection (as well as most human bites).
5. I highly doubt dog salvia has magical healing power. More likely to be due physical removal dirt and dead tissue of licking. SO wash your own wounds!

May 17, 2009 at 1:38 pm
(90) bambam says:

in my opinion dogs mouths are cleaner than ours even though they lick themselves in many places peopole wouldnt….i did my own test with the swabbing of both of our mouths and in a 2 week period the humans mouth collected so much bactreia it was gross

June 16, 2009 at 8:15 pm
(91) malona says:

a dogs mouth is cleaner dad !!!!!!!!!!!!!!!!!!

July 15, 2009 at 12:27 am
(92) ANGEL says:


July 30, 2009 at 2:42 am
(93) Afya Norbert says:

After brushing our teeth and flossing, human mouth is definitely cleaner. If a Human and a doggie went a day under the same conditions, Human mouth is AWFULLY dirty! On average, i think doggie mouth is cleaner

September 28, 2009 at 2:16 pm
(94) darthtomo says:

It depends on what a dog and a human have had in their mouths recently as to what bacteria levels are in the mouth at the time – nothing can alter that fact. It is therefore untrue to say with any degree of accuracy that a dog has a cleaner mouth than a human or a human has a cleaner mouth than a dog. However, germs/diseases are largely species-specific, so what affects a dog will probably not harm a human and human germs will not affect the dog (with the exception of things like rabies which are harmful to both).

October 7, 2009 at 8:11 pm
(95) matt says:

You know if you let a dog lick you mouth, lips, tongue or whatever then you are a person that may as well be making out with them. You probably let them lick your genitals too. You are sick and no amount of reasoning will matter. You try to make excuses that you make out with animals. If you do this around me, I am likely to hurt you very badly.

October 15, 2009 at 5:08 pm
(96) vet techs says:

If you’ve seen the mouths we’ve seen you would never believe that a dog’s mouth is cleaner than a human’s. Dog mouth’s are NOT cleaner than humans (unless you have a REALLY nasty mouth) but these comments have proven that many dogs are smarter than their owners.

October 29, 2009 at 1:05 pm
(97) darci says:

i dont understand how a dogs mouth wouyld be cleaner because they eat there own poop and clean themselves with there mouth when we take showers they get in trash and dirt all that so lol i dont get it

November 17, 2009 at 2:00 pm
(98) gabbie says:

i did a project ont this subject once and found out that dogs mouths really are cleaner than humans

November 19, 2009 at 9:09 am
(99) savannah says:

how are dog’s mouth cleaner when they eat there own poop

November 23, 2009 at 11:20 pm
(100) tuto noler says:

yes!!!!! They are way cleaner!!!!!

November 24, 2009 at 12:58 pm
(101) bre says:

i say that a dogs mouth is cleaner because if i have soar or something and my dog lick it it will dissapear the next 1 or 2 days thats what i say..

December 3, 2009 at 11:09 am
(102) kelsey says:

I think dogs mouths are cleaner than humans. My h.e teacher in high school also said this to my class and others so i do believe that dogs are the ones with the cleaner mouths:) !!

January 9, 2010 at 11:03 am
(103) Rebekah says:

I have done a bacterial experiment to find out if a dogs mouth is cleaner than a humans. The answer is no, a dogs mouth is indeed more dirtier than a humans. Research shows much more bacteria in a dogs mouth than in a humans.

February 6, 2010 at 2:25 pm
(104) jasonp says:

Dogs dont have cleaner mouths then humans. It is just simply impossible after all the butt licking hellos and garbage can love. But I will tell you it is much safer to french a dog then it is a person. Not saying im recommending it. It is safer simply because a dogs mouth has specie related bacteria in its mouth and is not tranferable to a human.

February 17, 2010 at 10:44 pm
(105) sarah says:

humans mouth are waaaay cleaner then a mutts mouth (i meant “mutt” in a good way so DONT GET ALL OVER ME!) anyways, do we eat our own poo? No. do we lick our private spots? No. we humans brush our teeth while dogs eat nasty stuff. infact, my dog eats her own POO! gross! thats why we dont let her lick us anymore (LOL) i like dogs very much cause our dogs protect us, Although, some dogs. are Annoying! my dogs bark is squeaky!, (really annoying!) and my dog licks her own wound (it has been there for over a year now!) and everytime she licks it it sounds like slow motion licking! (ANNOYINGER!) it feels like that someone is poking you like kinda like this “Poke! Poke! Poke! Poke! Poke!” and it just really annoys you, so we have to spray apple bitter on her wound so she doesnt like it (she also likes to attack and bite and pounce on us so we have to jerk her off or we pinch her to make her stop and shell give up) Anyways, back to the Story! humans mouth are cleaner then Dogs mouth. cause we brush our teeth we dont eat ,garbadge,poop,dead things, or lick our own private spots and lick other dogs ear wax (EWW!) my dog likes to lick her brothers ear wax alot and i scream out saying “EWW! your nasty!” LOL! (but she doesnt take it seriously)

btw? im 8 ;)

p.s. i didnt try to be mean just saying

February 17, 2010 at 11:00 pm
(106) sarah says:

oh, and also her wound just gets worse and she keeps on licking it.

February 17, 2010 at 11:05 pm
(107) gigi says:

i once ate chicken, out of a trash can, never got sick! :)

March 2, 2010 at 8:57 pm
(108) Mary Katherine says:

I think dogs have cleaner mouths than people because they drool so much that the germs just kinda fall off. We never drool unless were sleeping and we keep germs in there all the time. I only no 1 person who actually brushes their tongue and thats my dad. He goes all the way down his throught sometimes.

March 5, 2010 at 5:52 pm
(109) sara says:

woops i meant to say 18

March 12, 2010 at 2:48 pm
(110) TERESA says:


March 15, 2010 at 10:11 pm
(111) Emma says:

a dogs mouth!? pa’lease! those little rascals lick there own behineys! anyways id choose…….a HUMANS mouth! because dogs dont have *wiggles thumbs* THUMBS! :/

March 15, 2010 at 10:16 pm
(112) Emma says:

and Hannah, honey, you spelt weard wrong its “Weird” not “weard” learn some spelling lessons will ya?

March 16, 2010 at 10:39 pm
(113) mm says:

a dogs mouth is cleaner than a humans becuase they dont smoke chew tobacoo and other things like that

March 21, 2010 at 9:46 pm
(114) Smart@$$ says:

I don’t know about you, but I don’t think you are supposed to smoke chewing tabacco, hence the chewing. And I’m sorry this whole thread is pointless, thank you everyone for not answering the question…I’m going to wiki answers to see if I have any better luck there.

March 23, 2010 at 4:52 pm
(115) Lolly says:

thats all nasty dogs may seem cleaner but how their breath smells like crap and humans actually brush their teeth

April 11, 2010 at 12:29 am
(116) Carlos says:


May 24, 2010 at 12:51 pm
(117) Shemika says:

I don’t not think dog’s mouth are cleaner then human the eat off the ground. Then also eat out of other place that human would not.

June 25, 2010 at 1:57 pm
(118) tard says:

one thing everone seems to be overlooking, a bunch of people said that dogs lick themselves and humans do not, well that is true we dont lick ourselves but what about felatio, do you really think there are more germs licking yourself than someone else.

June 25, 2010 at 2:09 pm
(119) tad says:

i forgot to add, go ask your doctor which is worse to be bit by a human or a dog, other than the damage a dog can do, a bite from a human is way and i dont just mean a little bit worse i mean a lot worse as far as infection and gangreen are concerned, i know a guy got bit in a fight it was red swollen and full of infection by the following morning, took months of pills to clear the infection and heal properly, it wouldnt supprise me if humans had more bacteria in our mouths than a cat.

June 25, 2010 at 9:24 pm
(120) bill says:

My question is: After a dog licks it’s anus, how long does it take for it’s mouth to again get clean enough to kiss?

August 13, 2010 at 2:07 am
(121) Scientist says:

It is true that humans have more germs than a humans mouth. They may eat their own feces, puke, or lick themselves, although what is put into our food is worse. (And some people do “lick” each other during sexual intercourse.) This was done through the same procedure over 100 times and still resulted in the same conclusion. For that article Robert linked saying it’s not, that article is not even legitimate and credible. If one is going to link an article, don’t use google. And news reporters aren’t experts. If you want to cite anything use a credible source as in scholar approved articles and books. Google isn’t the answer to everything.

August 13, 2010 at 2:08 am
(122) Scientist says:

Humans have more germs than a dog’s mouth* sorry about that typo

October 21, 2010 at 3:29 pm
(123) ali says:

i also thank doges mouths are cleaner than huamen.

November 25, 2010 at 3:32 pm
(124) Hannah says:

I a’m 10 years old and I think a dogs mouth is cleaner because they can’t get cavities.

November 28, 2010 at 10:03 pm
(125) Sarah says:

For those annoying people than constantly nip at peoples spelling and grammar, get over yourself. People can sound stupid and still have perfect grammar. As long as it’s legible, I have no problem.
Also for that uh other sarah up there, please have the sense to NOT pinch your dog. Even though you’re 8. Dogs can only be ferocious if you bring them up that way. You wouldn’t pinch a misbehaving child would you? Dogs don’t mature past the human age 4.
I like what someone said about (some) dogs that have no bad breath and have never brushed their teeth. I think because dogs have less saliva in their mouth, less bacteria is in it. Not to mention the food my dog eats is hollistic and also meant to clean teeth. Our food is horrible to say the least. Even our crops are genetically modified… We may not lick our butts, but we have possibly done worse.

January 31, 2011 at 5:55 pm
(126) Felicia says:

My daughter and I did this project and the dog definately has a cleaner mouth. Also, I did some research to find out why a dog’s mouth is cleaner. A dog’s mouth is cooler than a human’s mouth, therefore bacteria can’t grow where it’s not warm.

February 7, 2011 at 7:13 am
(127) Slinky says:

Those who think a dogs mouth is ‘cleaner’, especially for no reason, are idiots. Bacteria still grows in cold.

No real educated person would say dogs mouths are cleaner.


March 26, 2011 at 9:48 pm
(128) allycat2002 says:

lol a dogs mouth is cleaner than a humans mouth because dogs wash there mouths ever day with water and people cleans there dogs mouth and also humans sometimes have bad teeth and do not brush there teeth there for a dogs mouth is cleaner than a humans mouth.

November 6, 2011 at 9:30 pm
(129) Chris says:

I have watched my dog eat another Dog’s pooh and have a snack out of the kitty litter box. I find it way to hard to belive that a dog has a cleaner mouth. Not to mention it is always licking her genitals.

December 4, 2011 at 10:55 pm
(130) Patriette says:

This is similar to the lie stating that we only use 10% of our brain. It’s degrading but not as bad as comparing us to dogs.

January 15, 2012 at 12:32 pm
(131) addie says:

I just completed a science fair project on this topic and after testing the bacteria on the petri dish I found that dogs mouths are actually much cleaner than human mouths, duck mouth, and even cat mouths. If anyone is to disagree I would consider that you do the project for yourself. It is a very infromative projects and actually quite easy to do…it is pretty interesting too.

February 16, 2012 at 7:01 pm
(132) tristan says:

i myself am working on this subject for an 8th grade science fair project except i added cats in with it so my question is this: which mouth has more bacteria a cat, dog, or a human? you tell me

March 21, 2012 at 4:00 pm
(133) madison says:


July 25, 2012 at 11:57 am
(134) Melody says:

I totally think dog mouth is so much cleaner ^-^ <3

October 26, 2012 at 2:31 pm
(135) meoooow says:

my dog licks my face all the time!!

April 10, 2013 at 10:53 am
(136) Destiny says:

Does anyone know what gene makes the dogs saliva kill the germs?

August 12, 2013 at 2:27 pm
(137) doug says:

You ppl who compare humans to dogs are a sad bunch..you kiss dogs in the mouth after they lick themselves..then you work in public restaurants..and stop comparing dogs to human babies..my child will always have a higher place in society than your “fur child”..get over yourselves

September 4, 2013 at 3:09 pm
(138) tutts says:

I seen my puppy put the craziness things in her mouth, like picking at a dead bird, eating her feces, licking herself, etc… I wont kiss her but will hug her, pat her… Besides, dogs may not have the same type of bacteria in their mouths as humans and vice versa… We may not even be able to fight off the bacteria a dog’s mouth maybe carrying around.. Dogs can pick up salmonella, tapeworms, hookworms, harbor it in their mouths, then pass that on to you by licking your face. They, as in dogs, maybe able to fight off those forms of bacteria but humans do not.. which is why we all make such a big deal about pasteurizing and so on. I do not think dogs mouths are cleaner just because Mythbusters did a petri dish test…

December 27, 2013 at 8:44 pm
(139) Andrea says:

People hate facing the fact the the animals they love can, not only make you sick but kill you! It doesn’t matter if you only feed you’re dog “pet foods” they can be contaminated with salmonella and other bacteria.. the number of bacteria isn’t as important as the type of bacteria.. so to all the people engaging in the outright disgusting act of swapping saliva with your dog you’re putting yourself and others at risk. ignorance doesn’t equal safety!

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