16 Popular Dog Myths Debunked (And What You Should Really Believe)

Dogs have been our companions for thousands of years, yet many myths and misunderstandings exist. Maybe you’ve heard that dogs only see in black and white or that you must be the “alpha” to train them. Some of these old ideas stick around even though science tells us otherwise.

Let’s go through 16 popular dog myths and see what’s true!

1. Once a Dog Bites, They Have to Be Put Down

It’s heartbreaking when a dog bites someone, and many people assume the worst — that the dog will keep biting and must be put down. But that’s not usually the case.

Biting is often a sign of fear, stress, pain, or a bad situation, not a personality flaw. Many dogs who bite once can live long, happy lives with the right training and environment. Working with a vet or behavior expert is essential to understand why the bite happened and how to prevent it again. In most cases, with patience and guidance, dogs can fully recover their trust and confidence.

2. Dog Saliva Heals Wounds

Older relatives might have said, “Let the dog lick it—it’ll heal faster!” Unfortunately, that’s a dangerous myth.

Dog mouths are full of bacteria. They lick everything — sidewalks, garbage, even their wounds. If your dog licks your cut, it could introduce harmful germs and cause infections instead of helping. The best thing you can do for yourself or your pup is clean wounds properly and keep them away from licking them.

3. Rescue Dogs Aren’t Good Pets

Many people wrongly believe rescue dogs are “problem dogs” or that something must be wrong with them if they’re in a shelter. But that’s not the case at all.

Most dogs in shelters are there because their owners face tough life changes like moving, illness, or money problems. Rescue dogs are just as loving, loyal, and trainable as dogs bought from breeders. Many rescued dogs seem even more grateful and bond deeply with the families who give them a second chance.

4. You Must Be the Alpha to Train Your Dog

The old-school idea that you have to dominate your dog to control them has been proven wrong by modern science.

Training based on fear and dominance can damage your relationship with your dog and create anxiety or aggression. Dogs learn best with positive reinforcement — treats, praise, play, and kindness. They want to work with us, not fight us for control. Trust and teamwork build much stronger, happier bonds than fear ever could.

5. Dogs Only See in Black and White

While it’s true dogs see fewer colors than humans, they don’t live in a completely gray world.

Dogs see mostly shades of blue, yellow, and gray. Their color vision helps them focus better during dawn and dusk, which made them great hunters long ago. Even though their world isn’t as colorful as ours, dogs are fantastic at spotting movement — something they’re way better at than humans!

6. Dogs Can Catch a Cold from Humans

When you’re sneezing and sniffling, you don’t have to worry about giving your dog a cold.

The viruses that make us sick rarely affect dogs. However, dogs have their “colds” versions, like kennel cough. If your dog gets sick, it’s more likely from another dog, not you. Just like you stay home when sick to protect others, keep your dog away from dog parks if they cough or runny nose.

7. Dogs Should Eat Like Wolves

Since dogs are related to wolves, some people think they should only eat raw meat. But dogs aren’t wolves anymore.

Dogs ‘ digestive systems have adapted over thousands of years of living alongside humans. They can digest grains, fruits, and vegetables, too. Feeding only meat can leave your dog missing essential nutrients. The best dog diets are balanced with meat, healthy fats, vitamins, and carbs.

8. A Dog’s Mouth is Cleaner Than a Human’s

No, your dog’s mouth isn’t some magical cleaning machine.

Dogs eat gross stuff — dirty water, dead things, trash — so their mouths are packed with bacteria. While their bacteria differ from ours, they’re not “cleaner.” If you love kissing your dog, don’t worry too much — but it’s always a good idea to keep up with regular dental cleanings and good hygiene.

9. One Dog Year Equals Seven Human Years

The old “multiply by seven” rule is an oversimplification.

New research shows that dogs age much faster in their early years, then the pace slows down. For example, a 1-year-old dog is about the same maturity as a 30-year-old human! Knowing this can help you better care for your dog through different life stages and catch age-related health issues earlier.

10. Dogs Always Cry Out When They’re in Pain

Dogs are masters at hiding pain. In the wild, showing weakness could get them attacked.

Your dog might not whine, limp, or cry even if they’re hurting. Watch for minor signs like stiffness, a change in how they walk, less interest in food, or acting withdrawn. It’s better to check with a vet if you notice anything unusual.

11. Sleeping with Your Dog Is Bad for You

Many people used to think sharing a bed with your dog was dirty or dangerous. But research says otherwise.

As long as your dog is healthy and clean, sleeping together can be comforting and help reduce stress. Many dog owners sleep better with their furry friends nearby. If you enjoy cuddling with your dog at night, you’re not doing anything wrong — you’re just getting extra love.

12. All Human Food Is Bad for Dogs

While some human foods like chocolate, grapes, and onions are toxic for dogs, not all human foods are bad.

Fruits like blueberries and apples (without seeds) can be a healthy treat. Plain-cooked chicken, rice, and veggies like carrots are dog-safe snacks. Always check first, keep portions small, and remember that treats should never replace your dog’s balanced meals.

13. Dogs Feel Guilt When They Look “Guilty”

It’s not guilt when you walk in and your dog looks guilty after a mess.

Dogs read your tone and body language. They might lower their body, tuck their tail, or avoid eye contact if you look mad. This isn’t them feeling guilty — it’s them trying to calm you down. So go easy on them when you find a chewed shoe!

14. A Wagging Tail Always Means Happiness

Tail wagging can mean many things — not just joy.

Dogs can wag when excited, scared, unsure, or even angry. Pay attention to the rest of the dog’s body: loose and wiggly (happy) or stiff and tense (nervous)? A tail is only part of the bigger picture.

15. Old Dogs Can’t Learn New Tricks

Good news: it’s never too late for a dog to learn!

Older dogs might take longer to learn new skills but can learn with patience and the right rewards. Training keeps their minds active and gives them a fun way to bond with you at any age.

16. Dogs Eat Grass Only When They’re Sick

While some dogs may eat grass with an upset stomach, most dogs eat grass because they like it.

Studies show that grass-eating is normal dog behavior. Wolves and wild dogs do it, too. As long as the grass isn’t treated with chemicals, there’s no reason to stop your dog from nibbling a little now and then.

A Warm Final Thought

Dogs are intelligent, loving, and endlessly fascinating, but even the best dog owners can get caught up in old myths.

Learning the real facts helps us take better care of our furry friends — and brings us even closer to them. When raising happy, healthy dogs, trust, love, and understanding go a long way. After all, they trust us wholeheartedly — the least we can do is keep learning how to be the best friend they deserve.