Daisy wouldn't leave Claire Guest alone. Instead of joining Guest's other dogs for a run in the park, the golden retriever with the soulful eyes kept nudging Guest's chest, and stared at her intently, somehow hoping she'd get the message.
"I was incredibly lucky to be told by Daisy."
When Guest got home, she detected a tiny lump in one of her breasts. She dismissed it, but her sister, who is a family doctor, insisted she get it checked out.
That saved her life. A series of tests, including a biopsy and a mammogram, revealed the cyst was benign. But doctors discovered a tumor hidden deep inside her chest wall, an insidious malignancy that normally isn't detected until the cancer has rampaged out of control throughout the body. "My prognosis would have been very poor," says Guest, who is an animal behavioralist. "I was incredibly lucky to be told by Daisy."
Ironically, at the time, Guest was training hearing dogs for the deaf—alerting them to doorbells or phones--for a charitable foundation. But she had been working on a side project to harness dogs' exquisitely sensitive sense of smell to spot cancer at its earliest and most treatable stages. When Guest was diagnosed with cancer two decades ago, however, the use of dogs to detect diseases was in its infancy and scientific evidence was largely anecdotal.
In the years since, Guest and the British charitable foundation she co-founded with Dr. John Church in 2008, Medical Detection Dogs (MDD), has shown that dogs can be trained to detect odors that predict a looming medical crisis hours in advance, in the case of diabetes or epilepsy, as well as the presence of cancers.
In a proof of principle study published in the BMJ in 2004, they showed dogs had better than a 40 percent success rate in identifying bladder cancer, which was significantly better than random chance (14 percent). Subsequent research indicated dogs can detect odors down to parts per trillion, which is the equivalent of sniffing out a teaspoon of sugar in two Olympic size swimming pools (a million gallons).
American scientists are devising artificial noses that mimic dogs' sense of smell, so these potentially life-saving diagnostic tools are widely available.
But the problem is "dogs can't be scaled up"—it costs upwards of $25,000 to train them—"and you can't keep a trained dog in every oncology practice," says Guest.
The good news is that the pivotal 2004 BMJ paper caught the attention of two American scientists—Andreas Mershin, a physicist at MIT, and Wen-Yee Yee, a chemistry professor at The University of Texas at El Paso. They have joined Guest's quest to leverage canines' highly attuned olfactory systems and devise artificial noses that mimic dogs' sense of smell, so these potentially life-saving diagnostic tools are widely available.
"What we do know is that this is real," says Guest. "Anything that can improve diagnosis of cancer is something we ought to know about."
Dogs have routinely been used for centuries as trackers for hunting and more recently, for ferreting out bombs and bodies. Dogs like Daisy, who went on to become a star performer in Guest's pack of highly trained cancer detecting canines before her death in 2018, have shared a special bond with their human companions for thousands of years. But their vastly superior olfaction is the result of simple anatomy.
Humans possess about six million olfactory receptors—the antenna-like structures inside cell membranes in our nose that latch on to the molecules in the air when we inhale. In contrast, dogs have about 300 million of them and the brain region that analyzes smells is, proportionally, about 40 times greater than ours.
Research indicates that cancerous cells interfere with normal metabolic processes, prompting them to produce volatile organic compounds (VOCs), which enter the blood stream and are either exhaled in our breath or excreted in urine. Dogs can identify these VOCs in urine samples at the tiniest concentrations, 0.001 parts per million, and can be trained to identify the specific "odor fingerprint" of different cancers, although teaching them how to distinguish these signals from background odors is far more complicated than training them to detect drugs or explosives.
For the past fifteen years, Andreas Mershin of MIT has been grappling with this complexity in his quest to devise an artificial nose, which he calls the Nano-Nose, first as a military tool to spot land mines and IEDS, and more recently as a cancer detection tool that can be used in doctors' offices. The ultimate goal is to create an easy-to-use olfaction system powered by artificial intelligence that can fit inside of smartphones and can replicate dogs' ability to sniff out early signs of prostate cancer, which could eliminate a lot of painful and costly biopsies.
Andreas Mershin works on his artificial nose.
Trained canines have a better than 90 percent accuracy in spotting prostate cancer, which is normally difficult to detect. The current diagnostic, the prostate specific antigen test, which measures levels of certain immune system cells associated with prostate cancer, has about as much accuracy "as a coin toss," according to the scientist who discovered PSA. These false positives can lead to unnecessary and horrifically invasive biopsies to retrieve tissue samples.
So far, Mershin's prototype device has the same sensitivity as the dogs—and can detect odors at parts per trillion—but it still can't distinguish that cancer smell in individual human patients the way a dog can. "What we're trying to understand from the dogs is how they look at the data they are collecting so we can copy it," says Mershin. "We still have to make it intelligent enough to know what it is looking at—what we are lacking is artificial dog intelligence."
The intricate parts of the artificial nose are designed to fit inside a smartphone.
At UT El Paso, Wen-Yee Lee and her research team has used the canine olfactory system as a model for a new screening test for prostate cancer, which has a 92 percent accuracy in tests of urine samples and could be eventually developed as a kit similar to the home pregnancy test. "If dogs can do it, we can do it better," says Lee, whose husband was diagnosed with prostate cancer in 2005.
The UT scientists used samples from about 150 patients, and looked at about 9,000 compounds before they were able to zero in on the key VOCs that are released by prostate cancers—"it was like finding a needle in the haystack," says Lee. But a more reliable test that can also distinguish which cancers are more aggressive could help patients decide their best treatment options and avoid invasive procedures that can render them incontinent and impotent.
"This is much more accurate than the PSA—we were able to see a very distinct difference between people with prostate cancer and those without cancer," says Lee, who has been sharing her research with Guest and hopes to have the test on the market within the next few years.
In the meantime, Guest's foundation has drawn the approving attention of royal animal lovers: Camilla, the Duchess of Cornwall, is a patron, which opened up the charitable floodgates and helped legitimize MDD in the scientific community. Even Camilla's mother-in-law, Queen Elizabeth, has had a demonstration of these canny canines' unique abilities.
Claire Guest, and two of MDDs medical detection dogs, Jodie and Nimbus, meet with queen Elizabeth.
"She actually held one of my [artificial] noses in her hand and asked really good questions, including things we hadn't thought of, like the range of how far away a dog can pick up the scent or if this can be used to screen for malaria," says Mershin. "I was floored by this curious 93-year-old lady. Half of humanity's deaths are from chronic diseases and what the dogs are showing is a whole new way of understanding holistic diseases of the system."
You are driving along the highway and see an electronic sign that reads: “3,238 traffic deaths this year.” Do you think this reminder of roadside mortality would change how you drive? According to a recent, peer-reviewed study in Science, seeing that sign would make you more likely to crash. That’s ironic, given that the sign’s creators assumed it would make you safer.
The study, led by a pair of economists at the University of Toronto and University of Minnesota, examined seven years of traffic accident data from 880 electric highway sign locations in Texas, which experienced 4,480 fatalities in 2021. For one week of each month, the Texas Department of Transportation posts the latest fatality messages on signs along select traffic corridors as part of a safety campaign. Their logic is simple: Tell people to drive with care by reminding them of the dangers on the road.
But when the researchers looked at the data, they found that the number of crashes increased by 1.52 percent within three miles of these signs when compared with the same locations during the same month in previous years when signs did not show fatality information. That impact is similar to raising the speed limit by four miles or decreasing the number of highway troopers by 10 percent.
The scientists calculated that these messages contributed to 2,600 additional crashes and 16 deaths annually. They also found a social cost, meaning the financial expense borne by society as a whole due to these crashes, of $377 million per year, in Texas alone.
The cause, they argue, is distracted driving. Much like incoming texts or phone calls, these “in-your-face” messages grab your attention and undermine your focus on the road. The signs are particularly distracting and dangerous because, in communicating that many people died doing exactly what you are doing, they cause anxiety. Supporting this hypothesis, the scientists discovered that crashes increase when the signs report higher numbers of deaths. Thus, later in the year, as that total mortality figure goes up, so do the percentage of crashes.
Boomerang effects happen when those with authority, in government or business, fail to pay attention to the science. These leaders rely on armchair psychology and gut intuitions on what should work, rather than measuring what does work.
That change over time is not simply a function of changing weather, the study’s authors observed. They also found that the increase in car crashes is greatest in more complex road segments, which require greater focus to navigate.
The overall findings represent what behavioral scientists like myself call a “boomerang effect,” meaning an intervention that produces consequences opposite to those intended. Unfortunately, these effects are all too common. Between 1998 and 2004, Congress funded the $1 billion National Youth Anti-Drug Media Campaign, which famously boomeranged. Using professional advertising and public relations firms, the campaign bombarded kids aged 9 to 18 with anti-drug messaging, focused on marijuana, on TV, radio, magazines, and websites. A 2008 study funded by the National Institutes of Health found that children and teens saw these ads two to three times per week. However, more exposure to this advertising increased the likelihood that youth used marijuana. Why? Surveys and interviews suggested that young people who saw the ads got the impression that many of their peers used marijuana. As a result, they became more likely to use the drug themselves.
Boomerang effects happen when those with authority, in government or business, fail to pay attention to the science. These leaders rely on armchair psychology and gut intuitions on what should work, rather than measuring what does work.
To be clear, message campaigns—whether on electronic signs or through advertisements—can have a substantial effect on behavior. Extensive research reveals that people can be influenced by “nudges,” which shape the environment to influence their behavior in a predictable manner. For example, a successful campaign to reduce car accidents involved sending smartphone notifications that helped drivers evaluate their performance after each trip. These messages informed drivers of their personal average and best performance, as measured by accelerometers and gyroscopes. The campaign, which ran over 21 months, significantly reduced accident frequency.
Nudges work best when rigorously tested with small-scale experiments that evaluate their impact. Because behavioral scientists are infrequently consulted in creating these policies, some studies suggest that only 62 percent have a statistically significant effect. Other research reveals that up to 15 percent of desired interventions may backfire.
In the case of roadside mortality signage, the data are damning. The new research based on the Texas signs aligns with several past studies. For instance, research has shown that increasing people’s anxiety causes them to drive worse. Another, a Virginia Tech study in a laboratory setting, found that showing drivers fatality messages increased what psychologists call “cognitive load,” or the amount of information your brain is processing, with emotionally-salient information being especially burdensome and preoccupying, thus causing more distraction.
Nonetheless, Texas, along with at least 28 other states, has pursued mortality messaging campaigns since 2012, without testing them effectively. Behavioral science is critical here: when road signs are tested by people without expertise in how minds work, the results are often counterproductive. For example, the Virginia Tech research looked at road signs that used humor, popular culture, sports, and other nontraditional themes with the goal of provoking an emotional response. When they measured how participants responded to these signs, they noticed greater cognitive activation and attention in the brain. Thus, the researchers decided, the signs worked. But a behavioral scientist would note that increased attention likely contributes to the signs’ failure. As the just-published study in Science makes clear, distracting, emotionally-loaded signs are dangerous to drivers.
But there is good news. First, in most cases, it’s very doable to run an effective small-scale study testing an intervention. States could set up a safety campaign with a few electric signs in a diversity of settings and evaluate the impact over three months on driver crashes after seeing the signs. Policymakers could ask researchers to track the data as they run ads for a few months in a variety of nationally representative markets for a few months and assess their effectiveness. They could also ask behavioral scientists whether their proposals are well designed, whether similar policies have been tried previously in other places, and how these policies have worked in practice.
Everyday citizens can write to and call their elected officials to ask them to make this kind of research a priority before embracing an untested safety campaign. More broadly, you can encourage them to avoid relying on armchair psychology and to test their intuitions before deploying initiatives that might place the public under threat.
I walked through the Dong Makkhai forest-products market, just outside of Vientiane, the laid-back capital of the Lao Peoples Democratic Republic or Lao PDR. Piled on rough display tables were varieties of six-legged wildlife–grasshoppers, small white crickets, house crickets, mole crickets, wasps, wasp eggs and larvae, dragonflies, and dung beetles. Some were roasted or fried, but in a few cases, still alive and scrabbling at the bottom of deep plastic bowls. I crunched on some fried crickets and larvae.
One stall offered Giant Asian hornets, both babies and adults. I suppressed my inner squirm and, in the interests of world food security and equity, accepted an offer of the soft, velvety larva; they were smooth on the tongue and of a pleasantly cool, buttery-custard consistency. Because the seller had already given me a free sample, I felt obliged to buy a chunk of the nest with larvae and some dead adults, which the seller mixed with kaffir lime leaves.
The year was 2016 and I was in Lao PDR because Veterinarians without Borders/Vétérinaires sans Frontières-Canada had initiated a project on small-scale cricket farming. The intent was to organize and encourage rural women to grow crickets as a source of supplementary protein and sell them at the market for cash. As a veterinary epidemiologist, I had been trained to exterminate disease spreading insects—Lyme disease-carrying ticks, kissing bugs that carry American Sleeping Sickness and mosquitoes carrying malaria, West Nile and Zika. Now, as part of a global wave promoting insects as a sustainable food source, I was being asked to view arthropods as micro-livestock, and devise management methods to keep them alive and healthy. It was a bit of a mind-bender.
The 21st century wave of entomophagy, or insect eating, first surged in the early 2010s, promoted by a research centre in Wageningen, a university in the Netherlands, conferences organized by the Food and Agriculture Organization of the United Nations, and enthusiastic endorsements by culinary adventurers and celebrities from Europeanized cultures. Headlines announced that two billion people around the world already ate insects, and that if everyone adopted entomophagy we could reduce greenhouse gases, mitigate climate change, and reign in profligate land and water use associated with industrial livestock production.
Furthermore, eating insects was better for human health than eating beef. If we were going to feed the estimated nine billion people with whom we will share the earth in 2050, we would need to make some radical changes in our agriculture and food systems. As one author proclaimed, entomophagy presented us with a last great chance to save the planet.
In 2010, in Kunming, a friend had served me deep-fried bamboo worms. I ate them to be polite. They tasted like French fries, but with heads.
The more recent data suggests that the number of people who eat insects in various forms, though sizeable, may be closer to several hundreds of millions. I knew that from several decades of international veterinary work. Sometimes, for me, insect eating has been simply a way of acknowledging cultural diversity. In 2010, in Kunming, a friend had served me deep-fried bamboo worms. I ate them to be polite. They tasted like French fries, but with heads. My friend said he preferred them chewier. I never thought about them much after that. I certainly had not thought about them as ingredients for human health.
Is consuming insects good for human health? Researchers over the past decade have begun to tease that apart. Some think it might not be useful to use the all-encompassing term insect at all; we don’t lump cows, pigs, chickens into one culinary category. Which insects are we talking about? What are they fed? Were they farmed or foraged? Which stages of the insects are we eating? Do we eat them directly or roasted and ground up?
The overall research indicates that, in general, the usual farmed insects (crickets, locusts, mealworms, soldier fly larvae) have high levels of protein and other important nutrients. If insects are foraged by small groups in Laos, they provide excellent food supplements. Large scale foraging in response to global markets can be incredibly destructive, but soldier fly larvae fed on food waste and used as a substitute for ground up anchovies for farmed fish (as Enterra Feed in Canada does) improves ecological sustainability.
Entomophagy alone might not save the planet, but it does give us an unprecedented opportunity to rethink how we produce and harvest protein.
The author enjoys insects from the Dong Makkhai forest-products market, just outside of Vientiane, the capital of the Lao Peoples Democratic Republic.
Between 1961 and 2018, world chicken production increased from 4 billion to 20 billion, pork from 200 million to over 100 billion pigs, human populations doubled from 3.5 billion to more than 7 billion, and life expectancy (on average) from 52 to 72 years. These dramatic increases in food production are the result of narrowly focused scientific studies, identifying specific nutrients, antibiotics, vaccines and genetics. What has been missing is any sort of peripheral vision: what are the unintended consequences of our narrowly defined success?
If we look more broadly, we can see that this narrowly defined success led to industrial farming, which caused wealth, health and labor inequities; polluted the environment; and created grounds for disease outbreaks. Recent generations of Europeanized people inherited the ideas of eating cows, pigs and chickens, along with their products, so we were focused only on growing them as efficiently as possible. With insects, we have an exciting chance to start from scratch. Because, for Europeanized people, insect eating is so strange, we are given the chance to reimagine our whole food system in consultation with local experts in Asia and Africa (many of them villagers), and to bring together the best of both locally adapted food production and global distribution.
For this to happen, we will need to change the dietary habits of the big meat eaters. How can we get accustomed to eating bugs? There’s no one answer, but there are a few ways. In many cases, insects are ground up and added as protein supplements to foods like crackers or bars. In certain restaurants, the chefs want you to get used to seeing the bugs as you eat them. At Le Feston Nu in Paris, the Arlo Guthrie look-alike bartender poured me a beer and brought out five small plates, each featuring a different insect in a nest of figs, sun-dried tomatoes, raisins, and chopped dried tropical fruits: buffalo worms, crickets, large grasshoppers (all just crunchy and no strong flavour, maybe a little nutty), small black ants (sour bite), and fat grubs with a beak, which I later identified as palm weevil larvae, tasting a bit like dried figs.
Some entomophagy advertising has used esthetically pleasing presentations in classy restaurants. In London, at the Archipelago restaurant, I dined on Summer Nights (pan fried chermoula crickets, quinoa, spinach and dried fruit), Love-Bug Salad (baby greens with an accompanying dish of zingy, crunchy mealworms fried in olive oil, chilis, lemon grass, and garlic), Bushman’s Cavi-Err (caramel mealworms, bilinis, coconut cream and vodka jelly), and Medieaval Hive (brown butter ice cream, honey and butter caramel sauce and a baby bee drone).
The Archipelago restaurant in London serves up a Love-Bug Salad: baby greens with an accompanying dish of zingy, crunchy mealworms fried in olive oil, chilis, lemon grass, and garlic.
Some chefs, like Tokyo-based Shoichi Uchiyama, try to entice people with sidewalk cooking lessons. Uchiyama's menu included hornet larvae, silkworm pupae, and silkworms. The silkworm pupae were white and pink and yellow. We snipped off the ends and the larvae dropped out. My friend Zen Kawabata roasted them in a small pan over a camp stove in the street to get the "chaff" off. We made tea from the feces of worms that had fed on cherry blossoms—the tea smelled of the blossoms. One of Uchiyama-san’s assistants made noodles from buckwheat dough that included powdered whole bees.
At a book reading in a Tokyo bookstore, someone handed me a copy of the Japanese celebrity scandal magazine Friday, opened to an article celebrating the “charms of insect eating.” In a photo, scantily-clad girls were drinking vodka and nibbling giant water bugs dubbed as toe-biters, along with pickled and fried locusts and butterfly larvae. If celebrities embraced bug-eating, others might follow. When asked to prepare an article on entomophagy for the high fashion Sorbet Magazine, I started by describing a clip of Nicole Kidman delicately snacking on insects.
Taking a page from the success story of MacDonald’s, we might consider targeting children and school lunches. Kids don’t lug around the same dietary baggage as the grownups, and they can carry forward new eating habits for the long term. When I offered roasted crickets to my grandchildren, they scarfed them down. I asked my five-year-old granddaughter what she thought: she preferred the mealworms to the crickets – they didn’t have legs that caught in her teeth.
Entomo Farms in Ontario, the province where I live, was described in 2015 by Canadian Business magazine as North America’s largest supplier of edible insects for human consumption. When visiting, I popped some of their roasted crickets into my mouth. They were crunchy, a little nutty. Nothing to get squeamish over. Perhaps the human consumption is indeed growing—my wife, at least, has joined me in my entomophagy adventures. When we celebrated our wedding anniversary at the Public Bar and Restaurant in Brisbane, Australia, the “Kang Kong Worms” and “Salmon, Manuka Honey, and Black Ants” seemed almost normal. Of course, the champagne helped.