A Quick Glance of the Information in This Article

  • Some key facts and examples about a dog’s sense of smell
  • An overview of a Dog’s Medical Detection facts
  • Examples of what puppies and adult dogs have been trained to successfully smell

Why Do Dogs Have Such a Great Ability with Their Noses?

Scientists state that dogs have a sense of smell of about 10,000 to 100,000 times as sensitive as humans which is astounding. Dogs have several hundred millions of scent glands versus about 5 or 6 million for humans.

A cancer-sniffing dog was very adamant of the presence of melanoma on a spot of a patient’s skin after doctors had already concluded the patient as cancer-free. A subsequent biopsy concluded that the dog was correct.

According to a PetMD article called “5 Dog Nose Facts You Probably Didn’t Know” by Amy Semigran, here are a few interesting facts about a dog’s sense of smell.

  • Two functions—one is for smell and the other is for respiration. Are you aware that dogs have the ability to take in and breathe out air simultaneously or at the same time?
  • A special scent-detecting organ that we humans aren’t born with. It is the vomeronasal organ which helps canines detect pheromones and chemicals released by animals that affect other members of the same species.
  • Smell separately with each nostril and can operate independently of one another. A dog’s brain uses the different odor profiles from each nostril and combines them to determine exactly where the objects are in their environment.
  • Evolved to help them survive and flourish over time and ultimately become lifelong companions of humans. Their nose helps them avoid predators or potentially dangerous creature, locate food for survival and ultimately find a mate to create future generations.

What Types of Medical Detection Are Dogs Being Trained For?

Dogs have been trained to detect a number of medical or health-affecting conditions which can be life saving for humans, especially for their owners. Some of the most prevalent ones include the following but it is not meant to be a comprehensive list:

  • Cancer
  • Low Blood Sugar
  • Narcolepsy
  • Seizures


Dogs are most known for their abilities to detect various types of cancer including lung, breast, skin and bladder. 

  • From a pilot cited in Integrative Cancer Therapies 5(1); 2006 called “Diagnostic Accuracy of Canine Scent Detection in Early- and Late-Stage Lung and Breast Cancers”, here is the conclusion: “Training was efficient and cancer identification was accurate; in a matter of weeks, ordinary household dogs with only basic behavioral “puppy training” were trained to accurately distinguish breath samples of lung and breast cancer patients from those of controls.”
  • Dogs have the ability to detect melanoma. Their noses may be assisted with the detection of chemicals that may be emanating from the skin lesions. An extract named the “Evidence for canine olfactory detection of melanoma” from the Applied Animal Behaviour Science, November 2004, cited where “dogs demonstrated reliable localization of melanoma tissue samples hidden on the skin of healthy volunteers.”
  • Testing has also shown that dogs have the ability to detect bladder cancer. In an abstract in the British Medical Journal called “Olfactory detection of human bladder cancer by dogs: proof of principle study”, the conclusion stated that “Dogs can be trained to distinguish patients with bladder cancer on the basis of urine odor more successfully than would be expected by chance alone.”

Low Blood Sugar (often referred to as hypoglycemia): 

Dogs are being trained to detect low blood sugar in Type 1 Diabetes patients. Low blood sugar can be extremely dangerous and even fatal if not addressed quickly.

  • Per Can Do Canines, “Diabetes Assist Dogs are trained to monitor smells in the air for a specific scent on the human breath that is related to rapidly dropping or low blood sugar levels.” When a person experiences hypoglycemia, their body produces a particular scent in their breath that dogs can detect.
  • There are also organizations which train dogs. For example, Diabetic Alert Dogs are trained to alert diabetic owners in advance of low blood sugar or high blood sugar (hyperglycemia) blood sugar events before either one becomes dangerous.


Dogs are believed to be able to pick up a scent when there is a biochemical change with their owners for this brain disorder. Studies have shown that dogs are able to provide up to a five minute advance notice of a pending event which can cause muscle tone loss while a person is awake, hallucinations and sleep paralysis.

  • In the study abstract called “Narcolepsy and Odor: Preliminary Report,” Luis Dominguez-Ortega, MD, PhD concludes that narcoleptic patients have a distinct typical odor that trained dogs are able to detect in many cases.
  • When a dog senses a coming event, they not only can provide a warning but help their owner prepare for an event by have them sitting or lying down to prevent a fall as well comforting their owner during and after the event.


Millions suffer from epileptic seizures. Dogs have shown the ability to warn their owners who have epilepsy that a seizure may be coming from within minutes to hours before it happens. How dogs can anticipate this impending condition is still unknown but nevertheless, it can be lifesaving.

  • Although no research study exists that identifies how dogs predict seizures, there are organizations such as Canine Partners for Life who train service dogs to detect impending seizures. They have shown success through their training program.


Life with our dogs is so helpful to our lives and health in so many ways. Not only are they such a great friend and wonderful companion, they have capabilities that continue to help us live more healthy and productive lives through their wonderful sense of smell.

For more information, resources, recommended reading materials and products for your pets, please go to https://dogloversforlife.com.

Dog Lovers for Life®, Dog Love and Your Health®

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