Why You Shouldn't Let Your Dog Lick Your Face, From a Vet

There are many ways that a dog can show physical affection, but the main one is licking. Dogs are prone to licking our hands, legs, feet and, especially, the face.

Debate rages as to whether you should let a dog lick your face, mainly due to misconceptions around their cleanliness, and specifically about how clean their mouths are.

Newsweek spoke to Judy Korman, DVM, veterinary consultant with formula company MYOS Pet, about whether you should let a dog's mouth near your face, how to keep your dog's mouth healthy, and any potential health risks.

Is My Dog's Mouth Cleaner Than Mine?

The short answer is no, dog mouths are not cleaner than those of humans. Dogs carry around 600 different types of bacteria species in their mouths.

"Like many myths, it is unclear how the myth that dogs have cleaner mouths than humans got started or took hold," Korman told Newsweek, "Perhaps it started with the observation that a dog's saliva must have healing properties since dogs typically lick their cuts and wounds, attempting to heal them."

Another possible explanation is that the saliva and bacteria in a dog's mouth create an environment that can prevent the formation of cavities. "The pH of a dog's mouth is less acidic than that of their human counterparts. This reduces the risk of cavities, but does not lower the risk of them getting periodontal disease, which is also caused by bacteria," said Korman.

Should I Let My Dog Lick My Face?

"It's important to remember that it is rare for people to acquire infections from their dogs," said Korman. However, there are some potential scenarios where it might not be the best idea.

"Dogs love to lick our faces, as this is often how they greet and show affection to members of their pack," she said. "If you enjoy face licks from your dog, then you should go for it, but be aware of certain situations that can make the practice a bit risky."

If you are immunocompromised, have a newborn baby, or allergic to the saliva of a dog, then it may be a good idea to avoid licks as certain germs and bacteria can be transmitted through dog saliva.

"Also, avoid face licks from dogs that have a tendency to eat their own or another animal's poop," advised Korman. "Germs, whose route of transmission is oral to fecal (e.g. some intestinal parasites, bacteria and viruses), can uncommonly be transferred from dogs to humans if the dog has recently ingested these germs by eating infected animal feces and subsequently licks your mouth."

There are some bacterial infections that can be transmitted to humans, but they are rare. According to the Centers for Disease Control a family of bacteria called Capnocytophaga that resides in the mouths of dogs can cause some issues for humans.

"Typically, the person would need to be bitten by the dog or have an open wound or cut for the bacteria to enter the person's body," said Korman, "Most people who have such contact with a dog do not become sick. People with weakened immune systems are at higher risk of becoming ill.

"Yersinia enterocolitica is another type of bacteria that can be transmitted to people by a dog bite. It may cause gastrointestinal disease in some, particularly those with weakened immune systems," she added.

Can I Eat Food My Dog Has Licked?

Unless your dog is incredibly well-trained or not at all interested in human food, it's usually a risk to leave them alone with your intended dinner. If they do have a penchant for human food, depending on whether it's a couple of licks or a complete decimation, you may wish to salvage some of your chow.

"It should be safe to eat food that your dog has licked, provided you know where your dog's mouth has been," Korman said, "Dogs that eat their or another animal's feces can pick up germs that they can then pass onto the food they lick. Theoretically, if a person then eats the food they can contract the germ and become infected. However, this type of transmission is rare."

It is possible for people to be allergic to canine saliva. "In fact," said Korman, "some studies show that it is the proteins in dog saliva, not dog dander or hair, that is the culprit causing the allergic reaction in people with dog allergies."

Top Tips For Keeping Your Dog's Mouth Clean

Although there are some risks involved in contact with dog saliva and mouth bacteria, they are low. However, there are things you can do to improve the cleanliness of your dog's mouth.

"Infections of the teeth and gums, called periodontal disease, is one of the most common problems affecting a dog's mouth," said Korman, adding, "It is associated with an overgrowth of certain bacteria in the dog's mouth and affects up to 90 percent of all dogs at some point in their lives. Your dog's bad breath may be a sign that they have periodontal disease. Regular teeth cleanings, performed by a veterinarian, are the best way to combat this disease."

The best way to keep your dog's mouth clean is to prevent the build-up of tartar and bacteria that can cause periodontal disease.

Korman's Top Tips For Keeping Your Dog's Mouth Clean

• Brush your dog's teeth daily
• Use antiseptic drops in their water
• Provide clean water daily
• Do not allow your dog to pick up feces
• Take your dog to the vet for regular (yearly) teeth cleanings
• Give your dog dental chews daily to prevent the buildup of tartar and bacteria

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