3 Ways Your Dog’s Nose Could Save Your Life
Published on May 02, 2012
When news headlines trumpet a dog sniffing out trouble and saving someone’s life, there’s often a dramatic story to tell: a fire, an explosive or a search-and-rescue operation. But there’s another remarkable way that dogs’ highly attuned sense of smell can save lives.
By following their noses, some canines can alert you to life-threatening health issues.
While there are thousands of first-person anecdotes about such scenarios, there’s also a growing body of scientific evidence and corroborating studies. Researchers across the world are investigating the potential of using dogs as medical early warning systems. With their heightened sense of smell — thousands of times more sensitive than humans' — it seems that canines can pick up the scent of certain diseases and medical conditions.
Could your dog give you a crucial early alert for a cancer screening? Or maybe save you from a seizure? Read on for three medical situations in which your pup might just come to the rescue.
Sniffing Out Cancer
Over the past few years, several research studies have utilized dogs in the pursuit of one of mankind’s deadliest diseases: cancer. Findings show that dogs can smell the presence of cancer in various samples, particularly those taken of the breath. These biomarkers could eventually lead the way to early detection and a greater chance of survival.
In 2011, a group of doctors at the Ambulante Pneumologie in Germany reported their findings from scent trials in which dogs pinpointed breath samples from patients with lung cancer. The dogs had a 71 percent success rate in identifying the cancer samples.
The Pine Street Foundation in California has published similarly encouraging results. In 2006, it released a study in which five trained dogs smelled breath samples from 55 lung cancer patients, 31 breast cancer patients and 83 healthy subjects. Over several months, and more than 12,000 trials, the dogs correctly selected the samples in roughly 90 percent of the cases, as well as across all four stages of the cancers.
Dr. Michael McCulloch, Pine Street Foundation’s research director, credits a 1989 report in The Lancet, a British medical journal, for initially piquing his interest in the novel idea. The report described a dog persistently sniffing a mole on his owner’s leg, which a doctor’s visit later revealed was a malignant melanoma. This reminded McCulloch’s team of a Chinese medical text from the third century B.C., which noted how human odors could change when the body is diseased.
“[We thought the dog] could do the same thing for other people, given the right training,” Dr. McCulloch says. “We then asked the question: If the dog could sniff a surface tumor, maybe we could train the dog, and maybe the same type of odor would occur from tumors located deeper in the body? And what if the odor could make its way to the lungs and out as exhaled breath? That was the hunch we were going on.”
Pine Street’s current project tackles the early detection of ovarian cancer. The team is collecting breath samples from patients with ovarian, fallopian tube or primary peritoneal cancer, along with healthy controls. And, once again, the dogs will sniff . . . and sniff . . . and sniff.
So far, the exact organic compounds that dogs can identify remain unknown. Dr. Touradj Solouki, a chemistry professor at Baylor University, has since joined the Pine Street project to examine these mysterious markers. With detailed analyses, Dr. McCulloch hopes that “[Solouki’s] lab can tell us what our Labs are sniffing!”
Detecting Blood Sugar Drops
Hundreds of personal stories attest to a dog’s ability to smell dangerous changes in blood sugar levels and warn of hypoglycemic attacks. And now scientific inquiries on diabetic alert dogs are getting under way.
In 1999, Mark Ruefenacht, a Type 1 diabetic, had his own close call when a dog roused him from a hypoglycemic stupor. Five years later, he founded Dogs 4 Diabetics, an organization that places medical assistance dogs trained in scent detection.
“The dog is an extra tool,” explains Carrie Skym, Dogs 4 Diabetics programs manager. When these assistance dogs, who act as a constant monitor, smell a significant blood sugar change in their owners, they’ll present a brinsel, a type of short stick attached to their collar. “It’s a very clear signal that says, ‘Hey, you need to check your blood sugars,' ” Skym says.
This wingman-like dedication was on full display at a recent Dogs 4 Diabetics graduation ceremony. “We had a 12-year-old boy giving a speech, and right there on stage, the dog alerted him,” Skym says.
The dogs are also trained to warn owners when they're fast asleep. “For a child, the dog might go wake up the parents,” Skym says. “Let’s face it, teenagers don’t wake up easily — even without the blood sugar issue.”
According to the organization, dogs can apparently detect a change faster than a standard blood glucose meter. Through their specialized training, “dogs can catch the scent 10 or 20 minutes before the blood sugar meters,” Skym notes. If the dog raises an alert but a meter reading indicates a normal glucose level, “we tell [owners] to wait 10 minutes and test again.” That extra time allows diabetics to more easily take preventive steps, so that a drop doesn’t become an emergency.
Scenting a Seizure
A growing number of epileptics and other people with seizure disorders rely on companion dogs to support them during an episode. These dogs often are trained stay with the patients during seizures to help keep them safe, but some even warn them of an impending attack.
As with diabetic alert dogs, much of the evidence is anecdotal, but seizure alert dogs seem to respond to scent and behavior clues. In the past decade, Seizure, a leading journal on epilepsy and other seizure disorders, has published a few surveys of epilepsy patients about their dogs’ response to seizures and any advance warning behaviors.
With a canine to alert them beforehand to a seizure, patients can make sure that they’re in a safe environment, call for help or otherwise take steps to avoid a life-threatening emergency. To get an owner's attention, the dogs adopt individual alert behaviors, such as licking their owners’ hands or barking.
Darlene Sullivan, founder and executive director of the assistance dog training and placement organization Canine Partners for Life, believes that scent helps a dog anticipate an attack. “We frequently see the dogs ‘air scenting’ (putting their nose in the air and obviously sniffing something) prior to many alerts,” she says.
Sullivan’s team reinforces this scent detection during training. “We have the trainers use a piece of clothing that the person was wearing during a seizure as a tug toy to reward them,” she explains. “This helps associate the scent with positive activities.”
Is There Such a Thing As an Ideal Alert Breed?
Anecdotal evidence shows that all kinds of dogs can raise medical alerts. Surveys and laboratory tests have studied Labrador Retrievers, Golden Retrievers and Portuguese Water Dogs.
“It seems to have more to do with temperament than breed or nose length,” Dr. McCulloch says. “The dogs who are friendly, well-disposed and eager to learn — those are the dogs who are really the stars.”