5 Dog Health Myths Vets Wish Would Go Away
Vet Reviewed by Dr. Jacob Klos, DVM
Happy April Fools' Day. In honor of things that aren't true, let's tackle five persistent dog health myths that veterinarians hear constantly and wish would finally disappear.
Myth #1: "A warm nose means your dog is sick."
This is one of the oldest and most widespread myths in dog ownership. The temperature and moisture level of a dog's nose fluctuates throughout the day based on activity, hydration, environment, and sleep. A dog can have a warm, dry nose and be perfectly healthy. A dog can also have a cool, wet nose and be quite ill.
The American Kennel Club confirms that nose temperature and moisture are unreliable indicators of health. If you're concerned about your dog's health, look at the full picture: energy level, appetite, behavior changes, and actual body temperature (normal range for dogs is 101 to 102.5 degrees Fahrenheit).
Myth #2: "Dogs eat grass because they're sick."
This one persists because it occasionally seems true. Some dogs do vomit after eating grass. But research suggests the behavior is far more common and far less alarming than most owners think.
A study published in Applied Animal Behaviour Science found that grass eating in dogs is common, with the majority of dogs not showing signs of illness before eating grass and not vomiting afterward. The behavior may be instinctive, related to taste preference, or connected to dietary fiber needs. In most cases, it's normal.
If your dog is eating grass obsessively, losing weight, or vomiting frequently, that's a different conversation. But occasional grass nibbling? Not a crisis.
Myth #3: "A dog's mouth is cleaner than a human's."
This one is particularly stubborn. Dogs' mouths contain hundreds of species of bacteria, many of which are different from those in human mouths. While the bacterial profiles are different enough that direct comparison is misleading, the idea that a dog's mouth is "cleaner" is not supported by science.
Dogs eat things off the ground, lick themselves, and do not brush their teeth. According to the American Veterinary Medical Association (AVMA), periodontal disease affects the majority of dogs by age three. A dog's mouth is many things. "Cleaner than yours" isn't one of them.
Myth #4: "You can't teach an old dog new tricks."
This is not just a myth. It's the opposite of what research shows. Older dogs can absolutely learn new behaviors, commands, and routines. Training engages the brain and can help slow cognitive decline.
A 2018 study in the journal Age found that cognitive training and enrichment had measurable positive effects on aging in dogs. Senior dogs benefit enormously from mental stimulation, short training sessions, and new experiences. The learning may take slightly longer, but the capacity is very much intact.
Myth #5: "Supplements don't do anything for dogs."
This one is more nuanced but worth addressing. The blanket claim that "supplements don't work" is not accurate. Certain ingredients have meaningful research behind them.
Glucosamine and chondroitin have been studied extensively for their role in joint comfort in dogs. Omega-3 fatty acids (particularly EPA and DHA) have documented benefits for skin health and inflammatory response. Probiotics have been studied for their positive effects on gut health and immune function in dogs.
The key is quality and consistency. Not all supplements are created equal, and taking them sporadically doesn't give the body enough to work with. The dogs that benefit most from supplementation are the ones whose owners choose evidence-backed ingredients and use them daily.
The bottom line? Stay curious, question what you hear, and when in doubt, ask your vet. The internet is full of confident advice. Not all of it is accurate.
