25 Common Dog Myths That Just Aren’t True

Dogs aren’t blind — and other common dog myths you shouldn’t believe.

25 Common Dog Myths That Just Aren’t True

You might think you know a lot about dogs, but how much of your knowledge is based on myths and old wives’ tales?

It’s time to separate fact from fiction and debunk some of the most common myths about our dogs.

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Dogs Are Colorblind

First of all, no human can see what a dog sees — so it’s a little tricky to work out where this myth came from.

But it’s not true that dogs only see in black and white.

Dogs Are Colorblind — Debunked

“Dogs just don’t see as vivid colors as we do,” explains Veterinarian Sara Ochoa, DVM, a consultant for doglab.com. “The main colors dogs see are yellow and blue.”

This is because the canine retina contains two of the three photo receptor types required to see color.

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Dogs Eat Grass When They Are Sick

Yes, it’s true that some dogs eat grass when they’re nauseous.

That’s because grass causes them to vomit, Ochoa says, but other dogs chomp on the green stuff for a variety of different reasons.

Dogs Eat Grass When They Are Sick — Debunked

“Often dogs just like to eat anything!” say the experts at The Puppy Academy. “It's fun for them to graze, sniff and taste what's out there, especially in new areas!”

So, don’t panic right away and assume something’s wrong if you see your dog is eating grass — they could just be feeling curious!

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

A Wagging Tail Means a Friendly Dog

Often, a wagging tail is the clearest sign of a happy dog.

It can show a dog is friendly, over-excited and wanting to play, but that’s not always the case, according to The Puppy Academy team.

A Wagging Tail Means a Friendly Dog — Debunked

A wagging tail can also be a sign of anxiety or aggression.

The Puppy Academy suggests looking for other behavioral signs, like relaxed eyes and ears, to ensure you're reading the situation correctly before assuming a dog is friendly.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

One Dog Year Equals 7 Human Years

This oft-cited “fact” isn’t actually a fact.

“Dogs do age faster than humans, but it is not necessarily true that every year is equal to seven for dogs,” says Karen Reese, animal behavior manager at Operation Kindness.

One Dog Year Equals 7 Human Years — Debunked

Dogs age faster in their younger years, so a six-month-old dog is close to a teenage human in maturity and development. “At 12 months old, the dog is akin to a 20-year-old human,” Reese explains. “After about 2 years old, they seem to age a little slower.”

Also, larger dogs sometimes seem to age faster than smaller dogs, but that is due to their typical lifespan. “For example, a dog with a seven-year lifespan will age much faster than one that is expected to live 12-15 years,” Reese says.

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A Cold, Wet Nose Means a Healthy Dog

Yes, a cold, wet nose can be a sign of a healthy dog. But that doesn’t mean other nose conditions can’t be healthy, too.

“A warm, dry nose does not mean that your dog is not healthy,” Ochoa says.

A Cold, Wet Nose Means a Healthy Dog — Debunked

The temperature, dryness and wetness of your dog’s nose can change throughout the course of a single day and shouldn’t be used as the sole indicator of health.

More reliable signs of potential health issues are behavioral changes, like a loss of appetite or decreased activity levels.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

A Dog’s Mouth Is Cleaner Than a Human Mouth

This is highly unlikely for obvious reasons. First of all, dogs don’t brush their teeth twice a day.

Plus, more than 80 percent of dogs over age three years have some form of periodontal disease, says VCA Animal Hospitals.

A Dog’s Mouth Is Cleaner Than a Human Mouth — Debunked

This myth may stem from the fact that when dogs lick their wounds, they seem to heal faster.

But that’s due to the process of licking, which stimulates blood flow and thus accelerates healing, and not because a canine mouth is cleaner than a human one.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

You Can’t Teach an Old Dog New Tricks

This dog myth is a hard no.

“You can absolutely teach an old dog new tricks!” says dog trainer Steffi Trott. “Dogs of any age can start to train and learn.”

You Can’t Teach an Old Dog New Tricks — Debunked

Not only can you teach an old dog new tricks, but Trott also points out that it’s actually quicker to teach an old dog a "new" trick in the sense that it’s something he hasn’t learned before, such as teaching him to spin in a circle or give you his paw for a "shake.”

On the other hand, it’s a lot harder to undo long-rehearsed behaviors. For instance, if your dog pulled on his leash for the last eight years, it will take a while to teach him to not do that, Trott says.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

Female Dogs Need to Go Through a Heat Cycle Before Being Spayed

Again, this isn’t true, says Ochoa.

In fact, she points out that spaying a dog before her first heat cycle will decrease her chance of mammary cancer in later life by 95 percent.

Female Dogs Need to Go Through a Heat Cycle Before Being Spayed — Debunked

According to the American Animal Hospital Association (AAHA) Canine Life Stage Guidelines, small-breed dogs (i.e., those estimated to weigh under 45 pounds as an adult) should be spayed prior to the first heat (around five to six months).

Deciding when to spay large-breed dogs (over 45 pounds projected adult body weight) involves considering many factors, including disease risk and lifestyle, with the help of a veterinarian.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

Dogs Look Guilty When They’ve Done Something Wrong

Your dog might have a particular expression when she’s chewed up the sofa or gone to the toilet on the rug, but it’s not guilt.

“Dogs do not feel the emotional state of guilt,” explains Marissa Sunny, CPDT-KA, senior specialist at the Best Friends Animal Society.

Dogs Look Guilty When They’ve Done Something Wrong — Debunked

When dogs look guilty, they are displaying appeasement behaviors.

“They do this because they have learned that it makes humans less angry, and therefore, they are safer,” says Sunny. “Dogs don't see things as right or wrong, rather they view things as safe or unsafe.”

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

A Female Dog Feels ‘Empty’ If She Doesn’t Have a Litter

Like the myth that female dogs need to have one litter before getting spayed, the notion that they’re “missing out” by not having a litter is an old wives’ tale.

“Most dogs are just fine never having puppies at all,” says Ochoa.

A Female Dog Feels ‘Empty’ If She Doesn’t Have a Litter — Debunked

In fact, dogs aren’t actually able to feel broody, and letting them have one litter before getting them spayed has no proven health or behavior benefits.

It could also contribute to the (already huge) numbers of unwanted dogs in shelters and rescue centers.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

It’s OK to Leave Your Dog in a Car on a Hot Day If Your Windows Are Down

This is never OK. “We do not advise ever leaving your pet unattended in a vehicle,” Reese says.

“Even with the windows down, it can become dangerously warm. Dogs need to have shade and fresh water to drink when it is hot outside.”

It’s OK to Leave Your Dog in a Car on a Hot Day If Your Windows Are Down — Debunked

Remember, dogs can’t sweat like humans do, so it’s much harder for them to regulate their body temperature and keep themselves cool.

Heatstroke can be fatal to pets in a matter of minutes, so it’s simply not worth the risk.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

All Rescue Dogs Are Damaged

This couldn’t be further from the truth. “Some dogs that are in rescue have never experienced any trauma,” says Trott.

“They might be there because their owners got sick or passed away. Or perhaps they ran away from home and could not be reunited with their family.”

All Rescue Dogs Are Damaged — Debunked

Even dogs in rescue who did experience trauma aren’t “damaged.” As Trott says, some dogs have amazing resilience and are able to overcome poor treatment. “Most puppies that are in rescue are the result of unplanned litters,” she adds. “They are essentially a ‘blank slate’ and can become fantastic companion dogs.”

“You get the added bonus of saving a life when you adopt a rescue dog!” adds Sunny.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

Pedigree Dogs Are Better Behaved

There are no inherent reasons why a purebred dog would be better behaved than a mixed dog breed.

“How well-behaved a dog is will depend on the owner's commitment to ongoing training as well as whether the dog's breed has a tendency to be interested in training and working together with the owner as a team,” Trott explains.

Pedigree Dogs Are Better Behaved — Debunked

Most herding dogs do really well in training, she adds, whereas independent breeds such as Huskies can be more difficult to train. “A herding dog mix might be better behaved than a purebred Husky,” she says.

On the other hand, most owners that acquire an expensive purebred dog are very likely to put in the effort and time required to train their dog well. Ultimately, it comes down to the time spent training as well as the individual dog's ability to learn.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

A Little Bit of Chocolate Is Fine for Dogs

This is definitely not true and can be harmful for your dog if you believe it to be.

Chocolate contains a chemical called theobromine, which is toxic to dogs. The amount of theobromine in chocolate depends varies — white chocolate only has a small amount, while dark chocolate contains much more.

A Little Bit of Chocolate Is Fine for Dogs — Debunked

Therefore, how dangerous chocolate is for a dog depends on the type of chocolate and the size of the dog, but it’s really not worth the risk.

It’s best to keep this sweet treat to yourself.

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I Need to Show My Dog Authority by Being the Pack Leader

This is completely unnecessary and can also be damaging for the relationship, Trott says.

“Dogs need predictable and kind owners,” she explains.

I Need to Show My Dog Authority by Being the Pack Leader — Debunked

“Being a ‘pack leader’ mostly entails being strict and rough, which dogs do not appreciate,” according to Trott.

Instead, be kind, predictable and fair in training to form the best relationship with your dog.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

If My Dog Has a Cold, I Can Catch It

Dog colds are not contagious to humans, says the American Kennel Club.

This means you can’t catch a cold from your dog (and likewise, your dog can’t pick up a human strain of a cold virus from you).

If My Dog Has a Cold, I Can Catch It — Debunked

What can happen is that dog colds and influenza can spread easily and quickly between dogs, meaning it’s important to take steps to help prevent transmission. So, don’t let your dog drink out of an infected dog’s water bowl or play with infected toys.

This is especially important for very young and very old dogs, plus pets with suppressed immune systems due to illness or medication.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

I Can Give My Dog Paracetamol for a Headache

It can be difficult to know if your dog has a headache (because they can’t tell you), but common signs to watch for are sickness and sensitivity to light and/or sound.

But even if you do believe they have one, any human painkillers, like paracetamol, are toxic to pets.

I Can Give My Dog Paracetamol for a Headache — Debunked

According to VCA Animal Hospitals, you should never give your dog paracetamol unless directed by your vet, as it can cause serious health issues like stomach ulcers and kidney and liver failure.

In severe cases, paracetamol can be fatal in dogs.

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Garlic Is Good for Fleas and Ticks

It would be great if this was true, but despite doing the round on the internet, there’s little science to back up the myth that garlic keeps your dog free from fleas and ticks.

Garlic Is Good for Fleas and Ticks — Debunked

Also, garlic has also been known to cause something called hemolytic anemia in dogs, which causes the body to attack and destroy its red blood cells.

This won’t necessarily happen to every dog who eats garlic, but it’s best not to find out.

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My Dog Is Hypoallergenic

Unfortunately, there’s no dog that is completely hypoallergenic.

However, it’s true that some breeds are less likely to produce an allergic response than others.

My Dog Is Hypoallergenic — Debunked

The American Kennel Club says dog breeds that have a predictable, non-shedding coat that produces less dander include Afghan Hound, Bichon Frise, Maltese and Poodle.

However, some sources say there are 50 dog breeds that you can choose from to avoid allergies.

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It’s Good for a Dog to Lick Their Wounds

While licking themselves might offer dogs some protection against bacteria, the American Kennel Club warns that those licks can do more harm than good.

It’s Good for a Dog to Lick Their Wounds — Debunked

In fact, your vet is likely to recommend an Elizabethan collar, a surgical suit and/or a bandage to protect your dog’s wound from licking following an injury or surgical procedure.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

Brushing My Dog’s Teeth Is Silly

VCA Animal Hospitals recommends brushing your dog’s teeth twice a day — just like you brush your own.

You might feel a little silly at first, but it’s an important step to help prevent dental disease, which affects a huge number of adult dogs.

Brushing My Dog’s Teeth Is Silly — Debunked

Your pooch might not like it at first, but like anything else, they’ll get used to it as part of their regular routine.

Also, brushing your dog’s teeth regularly means you’re looking in their mouth, which lets you spot health issues like abscesses and tumors.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

I Don’t Need to Vaccinate My Dog

The AAHA says dogs should definitely get vaccinated against canine distemper, infectious hepatitis, parvovirus and rabies.

As well as protecting your pet and other animals (and, in some cases, humans) from serious disease, vaccination also makes life easier for you if you plan on socializing your dog.

I Don’t Need to Vaccinate My Dog — Debunked

If you ever want to take your dog to puppy class or a boarding facility, you’ll need to provide proof of certain vaccines.

Your vet can advise you on the vaccinations your dog should get, and talk to you about the process and potential side effects.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

My Dog’s Thick Fur Coat Means They Stay Warm in Winter

A thick-haired Siberian Husky is far less susceptible to the cold than a Greyhound or a Boston Terrier, but all dogs are at risk of getting frostbite.

Dogs are most likely to develop frostbite on their paws, the tips of their ears and their scrotum (in males), and even breeds with ultra-thick coats don’t have a lot of protection in those parts.

My Dog’s Thick Fur Coat Means They Stay Warm in Winter — Debunked

You can still keep your pooch safe in cold temperatures if you don’t expose them for too long.

Signs that your dog may be too cold include shivering, shaking, whining or howling, says PETA.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

Some Dog Breeds Are More Aggressive Than Others

While different breeds may be more prone to higher energy or medical issues, every dog is an individual and should be treated as such, Sunny says.

“Each dog has a very different personality, experiences and environment — all of which shape how they act,” she adds.

Some Dog Breeds Are More Aggressive Than Others — Debunked

What is true, Trott warns, is that some dog breeds have a higher tendency to show aggression and guarding instincts than others, especially dogs that were bred to protect their property and owners. “Dogs with a high prey drive also can be aggressive towards smaller animals and children.”

Breeds that have a genetic disposition to be aggressive are Belgian Malinois, Mastiffs and Chows, she adds.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.

A Dog Will Cry If They’re in Pain

Dogs are less vocal creatures than humans, and although they may cry or whimper if they’re in pain, it’s not a given.

In fact, dogs — like many other species — may instinctively try to hide their pain to protect themselves from predators.

A Dog Will Cry If They’re in Pain — Debunked

By keeping a close eye on your dog, you’ll be able to spot changes in behavior that may suggest they’re in pain, as well as more obvious signs, like limping.

Want to help keep your dog healthy and save money on essential care? Get Lemonade pet health insurance.