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Do Dogs Know When You’re Sick? The Interesting Answer!

Written by: Rachael Gerkensmeyer

Last Updated on April 17, 2024 by Dogster Team

sick man lying in bed with his dog

Do Dogs Know When You’re Sick? The Interesting Answer!

Dogs are considered man’s best friend for various reasons. They are typically extremely loyal, they’re fun while adventuring outdoors, and they’re good at keeping their human companions company when nobody else is around. Dogs also happen to be highly observant. So, does your dog know when you are sick? It turns out that they might indeed be able to tell when you’re sick! Here’s how.

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A Dog’s Nose Can Tell Them About Your Health

A dog’s nose has about 300 million olfactory receptors1, which is much more than the 6 million or so that we humans have. Dogs can also process smells better than we can. So, while we can’t smell when a person’s odors change due to a change in volatile organic compounds within the body, a dog likely can.

For instance, a diabetic human’s bodily compounds change when their blood sugar levels rise or fall. A dog that is trained to do so can smell the change in compounds and alert their companion of blood sugar irregularities2. Some dogs also seem to be able to detect cancer through smell, either of the breath, skin tissue, or urine3.

dog nose close up shot
Image Credit: Miranda, Pixabay

So, it makes sense that a dog could detect when you are sick, even with a cold, as your organic compounds will change and produce a different smell than would be produced when you are in good health. However, a dog must know how a person should normally smell in order to detect a change in their body chemistry.

Therefore, your dog might be able to detect when you are sick, but chances are that they would not be able to detect an illness in someone whom they have never met or don’t know well. The exception would be dogs that are trained to detect the specific scents that certain cancers or other illnesses produce. In this case, they should be able to detect cancer or illness in anyone’s saliva or urine sample that they sniff.

It’s Not Just About a Dog’s Nose

Most dogs are good at understanding their companion’s body language and changes in behavior. They also know every aspect of their companion’s daily routine and use that routine to give themselves confidence that everything is going smoothly.

If you are not feeling well, you might rest or blow your nose more than usual. You may groan when getting up to make food or complete other tasks. You might even be a bit grumpy with everyone around you. You might drink more liquids to stay hydrated. Whatever the changes in your behavior, chances are that your dog will notice these things and understand that something is wrong — either you’re ill, depressed, or anxious.

How Dogs Might Respond If They Realize That Their Companion Is Sick

All dogs are different, so their response to detecting illness in their human companion can vary. Most dogs will stick closer to their companion’s side throughout the day, as if watching over them. They might pace back and forth nearby during a nap or movie-watching session. Your dog’s reaction might be subtle and hard to identify if they are already naturally cuddly and interactive with you.

girl hugging her pyschiatric service dog
Image Credit: Africa Studio, Shutterstock


A Quick Recap

Research seems to show that dogs can detect when their human companions are sick. Trained dogs do a better job of doing so, however, and untrained dogs may not obviously react to their detection of an illness. It comes down to the dog, their instincts, and their ability to communicate their concerns with those around them. It’s not a good idea to rely on a dog to detect when you are ill, as they may not alert you about it. Whenever you feel that something might be wrong, it’s a good idea to schedule an appointment with your doctor.

Featured Image Credit: Aleksey Boyko, Shutterstock

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