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A Nose for Trouble

Best-selling author Maria Goodavage explores the science behind how dogs are able to detect disease. By Jacob Muñoz

Maria Goodavage bonds with a Labrador retriever during a monthlong research trip to rural Japan in July.

Dog lovers around the world can attest to what makes dogs so important. They provide comfort and companionship, but man’s best friend might play a bigger role in human health than we ever thought.

Studies show that dog ownership is linked to better overall cardiovascular health and increased physical activity. Now New York Times best-selling author and veteran journalist Maria Goodavage ’84 looks at the remarkable disease-detecting abilities of dogs in her new book, Doctor Dogs: How Our Best Friends Are Becoming Our Best Medicine, due out Oct. 1.

Goodavage, who lives in San Francisco with her family and their yellow Lab, Gus, has been writing about dogs for much of her career.

“My dad used to tell us about when he was a homesick young solider in World War II, and how the military dogs the troops occasionally had among them saved lives by day and saved souls at night,” Goodavage recalls. “He said they always seemed to instinctively know who needed them the most, and they’d try to cheer up those soldiers.

“So I grew up with a great admiration for the powers of dogs to transform lives, to uplift us in the darkest times. When I got the chance to start writing about the human-dog bond in the early 1990s, it was a natural fit.”

This is her fourth book about working dogs — Soldier Dogs (2012) and Top Dog (2014) examine the lives of canines on the front lines, while Secret Service Dogs (2016) focuses on the White House’s most crucial animals. Her past books have shown how the well-developed olfactory system of dogs can alert humans to outside threats. In Doctor Dogs, however, Goodavage discusses their potential to warn us about the dangers within.

Her latest book explores the cutting-edge science of how dogs are able to detect and alert to health crises like diabetic lows, impending seizures, cardiac issues, migraines and serious sleep disorders. She also delves into the world of dogs working with scientists to uncover the scents of myriad diseases, including several types of cancer and Parkinson’s, in addition to deadly pathogens like antibiotic-resistant bacteria.

The human body emits volatile organic compounds (VOCs), some of which are associated with certain diseases and illnesses, such as diabetes or cancer. In our daily lives we are surrounded by VOCs, but our noses can’t distinguish ones that could be associated with illness.

But dogs have an advantage, Goodavage says. “Their sense of smell is exquisite. We have about 6 million olfactory receptors, but dogs have up to 300 million. They can sniff in stereo, and in parts per trillion — about a tablespoon of a substance in the equivalent of two Olympic-sized swimming pools. Their olfactory world is rich and vivid, much like our visual world.”

By using positive reinforcement, like loving praise and treats or toys, trainers have been able to teach dogs to detect and respond to medical emergencies. And using the same fun “paychecks,” scientists in research centers around the world are working with dogs — usually pet dogs who visit regularly — to detect diseases and pathogens.

“It seems that dogs, if trained well, are able to detect almost anything we ask them to,” Goodavage says. “For instance, we didn’t know until recently that something like the onset of seizures might come with its own unique smell.”

In her book, Goodavage also documents some of the unusual, but often lifesaving, behaviors of untrained pet dogs. For example, in one of the first documented cases, a dog named Baby Boo sniffed at and one day attacked a spot on her owner’s leg. The owner noticed a large bump after her pet’s outburst and later learned it was melanoma. The dog had helped detect the skin cancer before it spread.

In addition to physical illness, trained dogs are changing the lives of people with autism, survivors of traumatic experiences, and those with anxiety, schizophrenia and other mental illnesses. “They’re so in-tune with their person that they can sense when something is about to hit the fan,” Goodavage says. In addition to dog-detectable smells caused by illness and disease, “we’re learning now that there are scents to stress, panic and fear.”


“I grew up with a great admiration for the powers of dogs to transform lives, to uplift us in the darkest times. When I got the chance to start writing about the human-dog bond in the early 1990s, it was a natural fit.”

Goodavage spent seven years as the Northern California correspondent for USA Today, among other staff-writing positions for newspapers. She’s thankful for her education at the Medill School of Journalism, Media, Integrated Marketing Communication.

“My professors and working journalist instructors taught me the value of clear, highly readable writing that’s not just informative but alive. I learned to write well and think clearly under pressure,” she says.

Goodavage traveled around the world for her Doctor Dogs research. In pursuit of the best stories and latest science beyond the United States, she visited the United Kingdom, Hungary, Italy, Croatia, the Netherlands and Japan. In Japan she traveled several hours north of Tokyo, to Kaneyama, a small town with a high rate of stomach cancer, to learn more about a study using dogs to screen for cancer. It could inform future technology to create devices similar to dogs’ noses.

“Dogs are not going to be in laboratories waiting for your sample,” Goodavage says. “That’s not what anyone envisions. But dogs are going to be a step in helping us improve our technology so one day we may have early, inexpensive, accurate tests for many of the cancers that today usually aren’t detected until it’s too late.”

These advancements also hold personal weight for Goodavage.

“We have a family history of ovarian cancer,” she says. “I would love to see the work of the ovarian cancer–detection dogs and researchers at the University of Pennsylvania lead to a device to that can quickly and easily detect the earliest stages of ovarian cancer. Talk about dogs being our best friends!”

While she acknowledges the scientific, reward-driven explanation for the lifesaving behaviors of the doctor dogs who live with the people they help, she doesn’t hesitate to acknowledge that there’s probably also a strong element of love involved.

“Dogs are so beautifully attuned with people,” Goodavage says. “It’s like we’re extensions of each other. I really think they just want to see us be OK, and they’re happy to warn us when we’re not going to be OK.”

Jacob Muñoz, a rising junior from Ingleside, Ill., is studying journalism and psychology.

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Reader Responses

  • I am a retired physician who recently became trained with my dog for dog therapy. I make rounds once per week in a local hospital at inpatient and outpatient settings for patients and families and guests. I observe both acute and chronic and medical and psychological issues healed by the love of my dog.
    Also, hospital administrative, professional and support staff are loved and return to work with gratitude and smiles that change their thoughts and actions. This further benefits the patients.
    The reason is that love heals. This is a new frontier of improving health that benefits health care providers and those for whom they care.

    Alan Goldberg ’88 MBA, Chicago

  • This is a wonderful article about a fantastic phenomenon. There is a hockey player in the national hockey league, Max Domi, who is a Type 1 diabetic. He plays for the Montreal Canadiens and has a service dog that travels with him to help him detect low blood sugar. It is an incredible story.

    Greg Messina ’76 DDS, Rockford, Ill., via Northwestern Magazine

  • This sounds great! I plan on buying the book!

    Debby Parks ’66 Carlsbad, Calif., via Northwestern Magazine

  • Terrific story.

    Rhonda Milkowski ’72 MS, Chicago, via Northwestern Magazine

  • Excellent article about a potentially powerful gift our beloved dogs give us. Looking forward to reading the book.

    Marianne Oehser ’77 MBA, Huntsville, Ala., via Northwestern Magazine

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