Can Dogs Smell Sickness?

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Can dogs smell sickness? In short, yes. Dogs are amazing creatures and among their countless, priceless qualities is their olfactory senses (that is their sense of smell). A dog's sense of smell is about 100,000 times stronger than humans.  

When people are ill, their body chemistry changes; dogs can sense this change. Some dogs are even trained to sniff out illnesses like lung cancer just through a person's breath, bladder or urinary problems from a change in the smell of someone's urine, and they can even detect increased or decreased blood sugars in diabetics. Dogs are amazing little wonders, aren't they?

Signs a Dog Smells Sickness

Dogs are keen detectives when it comes to sensing changes in their people and those around them. If their master is someone who normally has a lot of pep in their step and is happy, when their master gets sick, a dog will likely notice that their owner is spending more time at rest. But it's not just behavioral changes that signal to your pup that something's wrong. They can actually detect unhappiness or depression by a drop in our oxytocin, dopamine and serotonin levels. Dogs are truly pawsome! 

When a dog is detecting sickness in their human, there are some tell-tale signs you can read simply from your doggy's body language. The dog will raise his snoot and tilt his head when he is trying to concentrate on the things, sounds and smells around him. He will be relaxed, yet alert. He will show no signs of aggression and may attempt to guard a person who isn't feeling well from other people. His ears will tilt toward what he is trying to hear. When he is sniffing something different, his tail will be held high and it will not wag.

Body Language

Some signs to look out for when your dog is potentially smelling a sickness are:
  • Alert
  • Guarding
  • Sniffing
  • Tail up
  • Ears up

Other Signs

Dogs that are trained to detect disease often display other signs such as:
  • Eye Contact with the Person
  • Trained Behaviors
  • Laying On or Close By Person

The History of Dogs Smelling Sicknesses

No doubt, as long as dogs have been around humans, they have been able to smell chemical changes in our bodies. At earlier points in history, this could have been seen as dogs possessing magical healing powers, before science could point to fantastic sniffers as the root cause of this seemingly "sixth sense".

It was only in the last century that we people finally caught on to just how helpful our pooch's sniffing powers could really be. This has led to training centers of all kinds being opened to help dogs fine-tune their sickness smelling and exhibit trained behaviors to warn their humans of danger from inside the body.

The Science Behind Dogs Smelling Sickness

Worldwide research shows that dogs can not only detect illness, but that by detecting illnesses, they save countless lives every day. A study in the British Medical Journal showed that dogs were able to detect bladder cancer simply from the smell of a subject's urine. A study from the Pine Street Foundation utilized five, trained scent dogs to detect or rule out cancer in 83 healthy participants and 83 cancer patients - within 90% accuracy.

Amazing right? Research has also shown that dogs can detect Parkinson's disease, can detect seizures before they happen and can sniff out several different forms of cancer such as ovarian, skin, lung, bowel, prostate and endometrial cancers.

Training Dogs to Sniff Illness

Scientists, doctors, and researchers use different means to train dogs to detect illness. In such instances, a dog is trained by sniffing small containers holding different blood plasma, urine samples or sputum; one of which is cancerous. When the dog stops sniffing and sits in front of the cancerous blood sample, they are rewarded with a nice treat or a toy. 

Dogs are trained to isolate that certain chemical in cancerous blood, breathe, urine or waste of any kind over a period of time. It takes time, patience, and dedication to train illness detection dogs, but through the work of their trainers, the dogs, and the information they collect, enable them to help sick people all over!

How to React When Your Dog Senses You Are Sick

  • Let them chill with you while you rest up - they will love every minute of your time together.
  • If your dog senses you are sad or tired, maybe he knows something you don't know, so you might want to make that doctor's appointment.
  • Let them spoil you, for a change, with extra doggie kisses and cuddles.

We Want to Hear About Your Dog Smelling Sicknesses!