Does My Dog Know When I'm Sick?

When you are not feeling well—perhaps you've had a recent bout with the flu or a nasty cold—you notice that your dog is always right at your side. Is that a coincidence, or can he really tell when you are not feeling well?

Dog guarding sick boy sleeping on sofa under plaid
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The short answer is yes. Though dogs do not know how to process empathy like human beings do, they can sniff out sickness. Some dogs are even known to be keen to when humans are having seizures or experiencing cancer. Learn exactly how the science works, and you'll be well informed the next time your dog is there for you when you're sick.

The science behind dogs and human illness

Dogs can sense sickness through their noses. Some dog breeds have up to 40 to 50 times the sense receptors from humans, which means that their sense of smell is roughly 100,000 times stronger than ours. If a person is sick, their body chemistry will alter. A dog will be able to sniff out those changes and alert him that a human is sick.

Incredibly, some pups are trained to sniff out volatile organic compounds that form in humans, which helps doctors detect early on if someone has cancer. With a track record of 90% or more accuracy, a dog can use his nose to determine where a mammary tumor is located, figure out if someone has prostate cancer or bladder by sniffing their urine and small lung cancer on a human's breath.

woman and dog in the room
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Dogs can also smell when people with diabetes experience changes in the blood sugar or there is a ketone presence. They have the ability to predict when an epileptic is about to have a seizure as well, and sense when a narcoleptic person is about to fall asleep and come to their aid. People with migraines can see that their dogs may whine or become distressed right before an attack, and remember to take their migraine medicine.

Getting close with your pup during rough times

Dogs perform best when they have scheduled lives, and they know when their daily routine—or yours—is not the same as usual. They can sense that something is off and may cozy up to you if you're sleeping more or lounging around the house.

Our pups also have the amazing ability to smell when there are changes in our oxytocin, serotonin and dopamine levels. If we are not feeling well, these hormones drop, and dogs can sense it. In turn, this can boost your hormones and make you feel better, so your dog may know that he is providing you with comfort.

Dogs are also known to sense when we are fearful or anxious by smelling our adrenaline and cortisol hormones. A dog's reaction can alert an owner to take deep breaths or practice meditation to relieve a panic attack that may be coming on.

Teen napping on the sofa with dog
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Why dogs are so comforting

Dogs make us feel better when we are sick without even being able to talk to us. They fully accept us for who we are and are not judgmental. They are truly man's best friend because of this.

Owning a dog has been shown to increase our happiness and prolong our lives. Having our pup around makes us less stressed and adds to our joy in life.

Cuddling with your dog on the couch, taking a nap with him or simply seeing him smiling and wagging his tail when you are feeling sick will instantly cheer you up. If you're having a tough day, perhaps you just need to take a break and spend a few minutes with your dog.