With Lab-Grown Chicken Nuggets, Dumplings, and Burgers, Futuristic Foods Aim to Seem Familiar
Shiok Meat's lab-grown "shrimp" dumplings, alongside a photo of the company's CTO, Ka Yi Ling, in a lab.
Sandhya Sriram is at the forefront of the expanding lab-grown meat industry in more ways than one.
"[Lab-grown meat] is kind of a brave new world for a lot of people, and food isn't something people like being brave about."
She's the CEO and co-founder of one of fewer than 30 companies that is even in this game in the first place. Her Singapore-based company, Shiok Meats, is the only one to pop up in Southeast Asia. And it's the only company in the world that's attempting to grow crustaceans in a lab, starting with shrimp. This spring, the company debuted a prototype of its shrimp, and completed a seed funding round of $4.6 million.
Yet despite all of these wins, Sriram's own mother won't try the company's shrimp. She's a staunch, lifelong vegetarian, adhering to a strict definition of what that means.
"[Lab-grown meat] is kind of a brave new world for a lot of people, and food isn't something people like being brave about. It's really a rather hard-wired thing," says Kate Krueger, the research director at New Harvest, a non-profit accelerator for cellular agriculture (the umbrella field that studies how to grow animal products in the lab, including meat, dairy, and eggs).
It's so hard-wired, in fact, that trends in food inform our species' origin story. In 2017, a group of paleoanthropologists caused an upset when they unearthed fossils in present day Morocco showing that our earliest human ancestors lived much further north and 100,000 years earlier than expected -- the remains date back 300,000 years. But the excavation not only included bones and tools, it also painted a clear picture of the prevailing menu at the time: The oldest humans were apparently chomping on tons of gazelle, as well as wildebeest and zebra when they could find them, plus the occasional seasonal ostrich egg.
These were people with a diet shaped by available resources, but also by the ability to cook in the first place. In his book Catching Fire: How Cooking Made Us Human, Harvard primatologist Richard Wrangam writes that the very thing that allowed for the evolution of Homo sapiens was the ability to transform raw ingredients into edible nutrients through cooking.
Today, our behavior and feelings around food are the product of local climate, crops, animal populations, and tools, but also religion, tradition, and superstition. So what happens when you add science to the mix? Turns out, we still trend toward the familiar. The innovations in lab-grown meat that are picking up the most steam are foods like burgers, not meat chips, and salmon, not salmon-cod-tilapia hybrids. It's not for lack of imagination, it's because the industry's practitioners know that a lifetime of food memories is a hard thing to contend with. So far, the nascent lab-grown meat industry is not so much disrupting as being shaped by the oldest culture we have.
Not a single piece of lab-grown meat is commercially available to consumers yet, and already so much ink has been spilled debating if it's really meat, if it's kosher, if it's vegetarian, if it's ethical, if it's sustainable. But whether or not the industry succeeds and sticks around is almost moot -- watching these conversations and innovations unfold serves as a mirror reflecting back who we are, what concerns us, and what we aspire to.
The More Things Change, the More They Stay the Same
The building blocks for making lab-grown meat right now are remarkably similar, no matter what type of animal protein a company is aiming to produce.
First, a small biopsy, about the size of a sesame seed, is taken from a single animal. Then, the muscle cells are isolated and added to a nutrient-dense culture in a bioreactor -- the same tool used to make beer -- where the cells can multiply, grow, and form muscle tissue. This tissue can then be mixed with additives like nutrients, seasonings, binders, and sometimes colors to form a food product. Whether a company is attempting to make chicken, fish, beef, shrimp, or any other animal protein in a lab, the basic steps remain similar. Cells from various animals do behave differently, though, and each company has its own proprietary techniques and tools. Some, for example, use fetal calf serum as their cell culture, while others, aiming for a more vegan approach, eschew it.
"New gadgets feel safest when they remind us of other objects that we already know."
According to Mark Post, who made the first lab-grown hamburger at Maastricht University in the Netherlands in 2013, the cells of just one cow can give way to 175 million four-ounce burgers. By today's available burger-making methods, you'd need to slaughter 440,000 cows for the same result. The projected difference in the purely material efficiency between the two systems is staggering. The environmental impact is hard to predict, though. Some companies claim that their lab-grown meat requires 99 percent less land and 96 percent less water than traditional farming methods -- and that rearing fewer cows, specifically, would reduce methane emissions -- but the energy cost of running a lab-grown-meat production facility at an industrial scale, especially as compared to small-scale, pasture-raised farming, could be problematic. It's difficult to truly measure any of this in a burgeoning industry.
At this point, growing something like an intact shrimp tail or a marbled steak in a lab is still a Holy Grail. It would require reproducing the complex musculo-skeletal and vascular structure of meat, not just the cellular basis, and no one's successfully done it yet. Until then, many companies working on lab-grown meat are perfecting mince. Each new company's demo of a prototype food feels distinctly regional, though: At the Disruption in Food and Sustainability Summit in March, Shiok (which is pronounced "shook," and is Singaporean slang for "very tasty and delicious") first shared a prototype of its shrimp as an ingredient in siu-mai, a dumpling of Chinese origin and a fixture at dim sum. JUST, a company based in the U.S., produced a demo chicken nugget.
As Jean Anthelme Brillat-Savarin, the 17th century founder of the gastronomic essay, famously said, "Show me what you eat, and I'll tell you who you are."
For many of these companies, the baseline animal protein they are trying to innovate also feels tied to place and culture: When meat comes from a bioreactor, not a farm, the world's largest exporter of seafood could be a landlocked region, and beef could be "reared" in a bayou, yet the handful of lab-grown fish companies, like Finless Foods and BlueNalu, hug the American coasts; VOW, based in Australia, started making lab-grown kangaroo meat in August; and of course the world's first lab-grown shrimp is in Singapore.
"In the U.S., shrimps are either seen in shrimp cocktail, shrimp sushi, and so on, but [in Singapore] we have everything from shrimp paste to shrimp oil," Sriram says. "It's used in noodles and rice, as flavoring in cup noodles, and in biscuits and crackers as well. It's seen in every form, shape, and size. It just made sense for us to go after a protein that was widely used."
It's tempting to assume that innovating on pillars of cultural significance might be easier if the focus were on a whole new kind of food to begin with, not your popular dim sum items or fast food offerings. But it's proving to be quite the opposite.
"That could have been one direction where [researchers] just said, 'Look, it's really hard to reproduce raw ground beef. Why don't we just make something completely new, like meat chips?'" says Mike Lee, co-founder and co-CEO of Alpha Food Labs, which works on food innovation more broadly. "While that strategy's interesting, I think we've got so many new things to explain to people that I don't know if you want to also explain this new format of food that you've never, ever seen before."
We've seen this same cautious approach to change before in other ways that relate to cooking. Perhaps the most obvious example is the kitchen range. As Bee Wilson writes in her book Consider the Fork: A History of How We Cook and Eat, in the 1880s, convincing ardent coal-range users to switch to newfangled gas was a hard sell. To win them over, inventor William Sugg designed a range that used gas, but aesthetically looked like the coal ones already in fashion at the time -- and which in some visual ways harkened even further back to the days of open-hearth cooking. Over time, gas range designs moved further away from those of the past, but the initial jump was only made possible through familiarity. There's a cleverness to meeting people where they are.
"New gadgets feel safest when they remind us of other objects that we already know," writes Wilson. "It is far harder to accept a technology that is entirely new."
Maybe someday we won't want anything other than meat chips, but not today.
Measuring Success
A 2018 Gallup poll shows that in the U.S., rates of true vegetarianism and veganism have been stagnant for as long as they've been measured. When the poll began in 1999, six percent of Americans were vegetarian, a number that remained steady until 2012, when the number dropped one point. As of 2018, it remained at five percent.
In 2012, when Gallup first measured the percentage of vegans, the rate was two percent. By 2018 it had gone up just one point, to three percent. Increasing awareness of animal welfare, health, and environmental concerns don't seem to be incentive enough to convince Americans, en masse, to completely slam the door on a food culture characterized in many ways by its emphasis on traditional meat consumption.
"A lot of consumers get over the ick factor when you tell them that most of the food that you're eating right now has entered the lab at some point."
Wilson writes that "experimenting with new foods has always been a dangerous business. In the wild, trying out some tempting new berries might lead to death. A lingering sense of this danger may make us risk-averse in the kitchen."
That might be one psychologically deep-seated reason that Americans are so resistant to ditch meat altogether. But a middle ground is emerging with a rise in flexitarianism, which aims to reduce reliance on traditional animal products. "Americans are eager to include alternatives to animal products in their diets, but are not willing to give up animal products completely," the same 2018 Gallup poll reported. This may represent the best opportunity for lab-grown meat to wedge itself into the culture.
Quantitatively predicting a population's willingness to try a lab-grown version of its favorite protein is proving a hard thing to measure, however, because it's still science fiction to a regular consumer. Measuring popular opinion of something that doesn't really exist yet is a dubious pastime.
In 2015, University of Wisconsin School of Public Health researchers Linnea Laestadius and Mark Caldwell conducted a study using online comments on articles about lab-grown meat to suss out public response to the food. The results showed a mostly negative attitude, but that was only two years into a field that is six years old today. Already public opinion may have shifted.
Shiok Meat's Sriram and her co-founder Ka Yi Ling have used online surveys to get a sense of the landscape, but they also take a more direct approach sometimes. Every time they give a public talk about their company and their shrimp, they poll their audience before and after the talk, using the question, "How many of you are willing to try, and pay, to eat lab-grown meat?"
They consistently find that the percentage of people willing to try goes up from 50 to 90 percent after hearing their talk, which includes information about the downsides of traditional shrimp farming (for one thing, many shrimp are raised in sewage, and peeled and deveined by slaves) and a bit of information about how lab-grown animal protein is being made now. I saw this pan out myself when Ling spoke at a New Harvest conference in Cambridge, Massachusetts in July.
"A lot of consumers get over the ick factor when you tell them that most of the food that you're eating right now has entered the lab at some point," Sriram says. "We're not going to grow our meat in the lab always. It's in the lab right now, because we're in R&D. Once we go into manufacturing ... it's going to be a food manufacturing facility, where a lot of food comes from."
The downside of the University of Wisconsin's and Shiok Meat's approach to capturing public opinion is that they each look at self-selecting groups: Online commenters are often fueled by a need to complain, and it's likely that anyone attending a talk by the co-founders of a lab-grown meat company already has some level of open-mindedness.
So Sriram says that she and Ling are also using another method to assess the landscape, and it's somewhere in the middle. They've been watching public responses to the closest available product to lab-grown meat that's on the market: Impossible Burger. As a 100 percent plant-based burger, it's not quite the same, but this bleedable, searable patty is still very much the product of science and laboratory work. Its remarkable similarity to beef is courtesy of yeast that have been genetically engineered to contain DNA from soy plant roots, which produce a protein called heme as they multiply. This heme is a plant-derived protein that can look and act like the heme found in animal muscle.
So far, the sciencey underpinnings of the burger don't seem to be turning people off. In just four years, it's already found its place within other American food icons. It's readily available everywhere from nationwide Burger Kings to Boston's Warren Tavern, which has been in operation since 1780, is one of the oldest pubs in America, and is even named after the man who sent Paul Revere on his midnight ride. Some people have already grown so attached to the Impossible Burger that they will actually walk out of a restaurant that's out of stock. Demand for the burger is outpacing production.
"Even though [Impossible] doesn't consider their product cellular agriculture, it's part of a spectrum of innovation," Krueger says. "There are novel proteins that you're not going to find in your average food, and there's some cool tech there. So to me, that does show a lot of willingness on people's part to think about trying something new."
The message for those working on animal-based lab-grown meat is clear: People will accept innovation on their favorite food if it tastes good enough and evokes the same emotional connection as the real deal.
"How people talk about lab-grown meat now, it's still a conversation about science, not about culture and emotion," Lee says. But he's confident that the conversation will start to shift in that direction if the companies doing this work can nail the flavor memory, above all.
And then proving how much power flavor lords over us, we quickly derail into a conversation about Doritos, which he calls "maniacally delicious." The chips carry no health value whatsoever and are a native product of food engineering and manufacturing — just watch how hard it is for Bon Appetit associate food editor Claire Saffitz to try and recreate them in the magazine's test kitchen — yet devotees remain unfazed and crunch on.
"It's funny because it shows you that people don't ask questions about how [some foods] are made, so why are they asking so many questions about how lab-grown meat is made?" Lee asks.
For all the hype around Impossible Burger, there are still controversies and hand-wringing around lab-grown meat. Some people are grossed out by the idea, some people are confused, and if you're the U.S. Cattlemen's Association (USCA), you're territorial. Last year, the group sent a petition to the USDA to "exclude products not derived directly from animals raised and slaughtered from the definition of 'beef' and meat.'"
"I think we are probably three or four big food safety scares away from everyone, especially younger generations, embracing lab-grown meat as like, 'Science is good; nature is dirty, and can kill you.'"
"I have this working hypothesis that if you look at the nation in 50-year spurts, we revolve back and forth between artisanal, all-natural food that's unadulterated and pure, and food that's empowered by science," Lee says. "Maybe we've only had one lap around the track on that, but I think we are probably three or four big food safety scares away from everyone, especially younger generations, embracing lab-grown meat as like, 'Science is good; nature is dirty, and can kill you.'"
Food culture goes beyond just the ingredients we know and love — it's also about how we interact with them, produce them, and expect them to taste and feel when we bite down. We accept a margin of difference among a fast food burger, a backyard burger from the grill, and a gourmet burger. Maybe someday we'll accept the difference between a burger created by killing a cow and a burger created by biopsying one.
Looking to the Future
Every time we engage with food, "we are enacting a ritual that binds us to the place we live and to those in our family, both living and dead," Wilson writes in Consider the Fork. "Such things are not easily shrugged off. Every time a new cooking technology has been introduced, however useful … it has been greeted in some quarters with hostility and protestations that the old ways were better and safer."
This is why it might be hard for a vegetarian mother to try her daughter's lab-grown shrimp, no matter how ethically it was produced or how awe-inspiring the invention is. Yet food cultures can and do change. "They're not these static things," says Benjamin Wurgaft, a historian whose book Meat Planet: Artificial Flesh and the Future of Food comes out this month. "The real tension seems to be between slow change and fast change."
In fact, the very definition of the word "meat" has never exclusively meant what the USCA wants it to mean. Before the 12th century, when it first appeared in Old English as "mete," it wasn't very specific at all and could be used to describe anything from "nourishment," to "food item," to "fodder," to "sustenance." By the 13th century it had been narrowed down to mean "flesh of warm-blooded animals killed and used as food." And yet the British mincemeat pie lives on as a sweet Christmas treat full of -- to the surprise of many non-Brits -- spiced, dried fruit. Since 1901, we've also used this word with ease as a general term for anything that's substantive -- as in, "the meat of the matter." There is room for yet more definitions to pile on.
"The conversation [about lab-ground meat] has changed remarkably in the last six years," Wurgaft says. "It has become a conversation about whether or not specific companies will bring a product to market, and that's a really different conversation than asking, 'Should we produce meat in the lab?'"
As part of the field research for his book, Wurgaft visited the Rijksmuseum Boerhaave, a Dutch museum that specializes in the history of science and medicine. It was 2015, and he was there to see an exhibit on the future of food. Just two years earlier, Mark Post had made that first lab-grown hamburger about a two-and-a-half hour drive south of the museum. When Wurgaft arrived, he found the novel invention, which Post had donated to the museum, already preserved and served up on a dinner plate, the whole outfit protected by plexiglass.
"They put this in the exhibit as if it were already part of the historical records, which to a historian looked really weird," Wurgaft says. "It looked like somebody taking the most recent supercomputer and putting it in a museum exhibit saying, 'This is the supercomputer that changed everything,' as if you were already 100 years in the future, looking back."
It seemed to symbolize an effort to codify a lab-grown hamburger as a matter of Dutch pride, perhaps someday occupying a place in people's hearts right next to the stroopwafel.
"Who's to say that we couldn't get a whole school of how to cook with lab-grown meat?"
Lee likes to imagine that part of the legacy of lab-grown meat, if it succeeds, will be to inspire entirely new fads in cooking -- a step beyond ones like the crab-filled avocado of the 1960s or the pesto of the 1980s in the U.S.
"[Lab-grown meat] is inherently going to be a different quality than anything we've done with an animal," he says. "Look at every cut [of meat] on the sphere today -- each requires a slightly different cooking method to optimize the flavor of that cut. Who's to say that we couldn't get a whole school of how to cook with lab-grown meat?"
At this point, most of us have no way of trying lab-grown meat. It remains exclusively available through sometimes gimmicky demos reserved for investors and the media. But Wurgaft says the stories we tell about this innovation, the articles we write, the films we make, and yes, even the museum exhibits we curate, all hold as much cultural significance as the product itself might someday.
Lab-grown insect meat could be the protein source of the future.
Agriculture in the 21st century is not as simple as it once was. With a population seven billion strong, a climate in crisis, and sustainability in farming practices on everyone's radar, figuring out how to feed the masses without destroying the Earth is a pressing concern.
Tufts scientists argue that insect cells may be better suited to lab-created meat protein than traditional farm animal cells.
In addition to low-emission cows and drone pollinators, there's a promising new solution on the table. How does "lab-grown insect meat" grab you?
Writing in Frontiers in Sustainable Food Systems, researchers at Tufts University say insects that are fed plants and genetically modified for maximum growth, nutrition, and flavor could be the best, greenest alternative to our current livestock farming practices. This lab-grown protein source could produce high volume, nutritious food without the massive resources required for traditional animal agriculture.
"Due to the environmental, public health, and animal welfare concerns associated with our current livestock system, it is vital to develop more sustainable food production methods," says lead author Natalie Rubio. Could insect meat be the key?
Next Up
New sustainable food production includes what's called "cellular agriculture," an emerging industry and field of study in which meat and dairy are produced via cells in a lab instead of whole animals. So far, scientists have primarily focused on bovine, porcine, and avian cells to create this "cultured meat."
But the Tufts scientists argue that insect cells may be better suited to lab-created meat protein than traditional farm animal cells.
"Compared to cultured mammalian, avian, and other vertebrate cells, insect cell cultures require fewer resources and less energy-intensive environmental control, as they have lower glucose requirements and can thrive in a wider range of temperature, pH, oxygen, and osmolarity conditions," reports Rubio.
"Alterations necessary for large-scale production are also simpler to achieve with insect cells, which are currently used for biomanufacturing of insecticides, drugs, and vaccines," she adds.
They still have some details to hash out, however, including how to make cultured insect meat more like the steak and chicken we're all familiar with.
"Despite this immense potential, cultured insect meat isn't ready for consumption," says Rubio. "Research is ongoing to master two key processes: controlling development of insect cells into muscle and fat, and combining these in 3D cultures with a meat-like texture." They are currently experimenting with mushroom-derived fiber to tackle the latter.
People would still be able to eat meat—it would just come from a different source.
Open Questions
As the report points out, one thing that makes cellular agriculture an attractive alternative to high-density animal farming is that it doesn't require consumers to change their behaviors. People would still be able to eat meat—it would just come from a different source.
But the big question remains: How will lab-grown insect meat taste? Will the buggers really taste as good as burgers?
And, of course, there's the "ew" factor. Meat alternatives have proven to work for some people—Tofurky is still in business, after all—but it may be a hard sell to get the masses to jump on board with eating bugs. Consuming creepy crawlies sounds simply unpalatable to many, and the term "lab-grown, cellular insect meat" doesn't help much. Perhaps an entirely new nomenclature is in order.
Another question is whether or not folks will trust such scientifically-created food. People already use the term "frankenfood" to refer to genetic modification -- even though the vast majority of the corn and soybeans planted in the U.S. today are genetically engineered, and other major crops with GM varieties include potatoes, apples, squash, and papayas. Still, combining GM technology with eating insects may be a hard sell.
However, we're all going to have to get used to trying new things if we want to leave a habitable home for our children. If a lab-grown bug burger can save the planet, maybe it's worth a shot.
A baby who cannot tolerate milk due to an allergy.
Like any life-threatening medical condition that affects children, food allergies can traumatize more than just the patient. My wife and I learned this one summer afternoon when our daughter was three years old.
Emergency room visits for anaphylaxis in children more than doubled from 2010 to 2016.
At an ice cream parlor, I gave Samantha a lick of my pistachio cone; within seconds, red blotches erupted on her skin, her lips began to swell, and she complained that her throat felt funny. We rushed her to the nearest emergency room, where a doctor injected her with epinephrine. Explaining that the reaction, known as anaphylaxis, could have been fatal if left unchecked, he advised us to have her tested for nut allergies—and to start carrying an injector of our own.
After an allergist confirmed Sam's vulnerability to tree nuts and peanuts, we figured that keeping her safe would be relatively simple. But food allergies often come in bunches. Over the next year, she wound up back in the ER after eating bread with sesame seeds at an Italian restaurant, and again after slurping buckwheat noodles at our neighborhood Japanese. She hated eggs, so we discovered that (less severe) allergy only when she vomited after eating a variety of products containing them.
In recent years, a growing number of families have had to grapple with such challenges. An estimated 32 million Americans have food allergies, or nearly 10 percent of the population—10 times the prevalence reported 35 years ago. The severity of symptoms seems to be increasing, too. According to a study released in January by Food Allergy Research & Education (FARE), a Virginia-based nonprofit, insurance claims for anaphylactic food reactions rose 377 percent in the U.S. from 2007 to 2016.
Because food allergies most commonly emerge in childhood, these trends are largely driven by the young. An insurance-industry study found that emergency room visits for anaphylaxis in children more than doubled from 2010 to 2016. Peanut allergies, once rare, tripled in kids between 1997 and 2008. "The first year, it was 1 in 250," says Scott Sicherer, chief of pediatric allergy and immunology at New York City's Mount Sinai Hospital, who led that study. "When we did the next round of research, in 2002, it was 1 in 125. I thought there must be a mistake. But by 2008, it was 1 in 70."
The forces behind these dire statistics—as well as similar numbers throughout the developed world—have yet to be positively identified. But the leading suspects are elements of our modern lifestyle that can throw the immune system out of whack, prompting potentially deadly overreactions to harmless proteins. Although parents can take a few steps that might lessen their children's risk, societal changes may be needed to brighten the larger epidemiological picture.
Meanwhile, scientists are racing to develop therapies that can induce patients' hyped-up immune defenses to chill. And lately, they've made some big strides toward that goal.
A Variety of Culprits
In the United States, about 90 percent of allergic reactions come from eight foods: milk, eggs, peanuts, tree nuts, soy, wheat, fish, and shellfish. The list varies from country to country, depending on dietary customs, but what the trigger foods all have in common is proteins that can survive breakdown in the stomach and enter the bloodstream more or less intact.
"When we were kids, we played in the dirt. Today, children tend to be on their screens, inside sealed buildings."
A food allergy results from a chain of biochemical misunderstandings. The first time the immune system encounters an allergen (as a protein that triggers an allergy is known), it mistakes the substance for a hostile invader—perhaps a parasite with a similar molecular profile. In response, it produces an antibody called immunoglobin E (IgE), which is designed to bind to a specific protein and flag it for attack. These antibodies circulate through the bloodstream and attach to immune-system foot soldiers known as mast cells and basophils, which congregate in the nose, throat, lungs, skin, and gastrointestinal tract.
The next time the person is exposed to the allergen, the IgE antibodies signal the warrior cells to blast the intruder with histamines and other chemical weapons. Tissues in the affected areas swell and leak fluid; blood pressure may fall. Depending on the strength of the reaction, collateral damage to the patient can range from unpleasant—itching, runny nose, nausea—to catastrophic.
This kind of immunological glitchiness runs in families. Genome-wide association studies have identified a dozen genes linked to allergies of all types, and twin studies suggest that about 80 percent of the risk of food allergies is heritable. But why one family member shows symptoms while another doesn't remains unknown. Nor can genetics explain why food allergy rates have skyrocketed in such a brief period. For that, we must turn to the environment.
First, it's important to note that rates of all allergies are rising—including skin and respiratory afflictions—though none as rapidly or with as much risk of anaphylaxis as those involving food. The takeoff was already underway in the late 1980s, when British epidemiologist David P. Strachan found that children in larger households had fewer instances of hay fever. The reason, he suggested, was that their immune systems were strengthened by exposure to their siblings' germs. Since then, other researchers have discerned more evidence for Strachan's "hygiene hypothesis": higher rates of allergy (as well as autoimmune disorders) in cities versus rural areas, in industrialized countries versus developing ones, in lab animals raised under sterile conditions versus those exposed to germs.
Fending off a variety of pathogens, experts theorize, helps train the immune system to better distinguish friend from foe, and to respond to threats in a more nuanced manner. In an era of increasing urbanization, shrinking family sizes, and more sheltered lifestyles, such conditioning may be harder to come by. "When we were kids, we played in the dirt," observes Cathryn R. Nagler, a professor and food allergy researcher at the University of Chicago. "Today, children tend to be on their screens, inside sealed buildings."
But other factors may be driving the allergy epidemic as well. More time indoors, for example, means less exposure to sunlight, which can lead to a deficiency in vitamin D—a nutrient crucial to immune system regulation. The growing popularity of processed foods filled with refined fats and sugars may play a role, along with rising rates of obesity, by promoting tissue inflammation that could increase some people's risk of immunological mayhem. And the surge in allergies also correlates with several trends that may be altering the human microbiome, the community of microbes (including bacteria, viruses, and fungi, among others) that inhabits our guts, skin, and bodily orifices.
The microbiome connection may be particularly relevant to food allergies. In 2014, a team led by Nagler published a landmark study showing that Clostridia, a common class of gut bacteria, protects against these allergies. When the researchers fed peanut allergens to germ-free mice (born and raised in sterile conditions) and to mice treated with antibiotics as newborns (reducing their gut bacteria), the animals showed a strong immunological response. This sensitization could be reversed, however, by reintroducing Clostridia—but not another class of bacteria, Bacteroides—into the mice. Further experiments revealed that Clostridia caused immune cells to produce high levels of interleukin-22 (IL-22), a signaling molecule known to decrease the permeability of the intestinal lining.
"In simple terms," Nagler says, "what we found is that these bacteria prevent food allergens from gaining access to the blood in an intact form that elicits an allergic reaction."
A growing body of evidence suggests that our eating habits are throwing our gut microbiota off-balance, in part by depriving helpful species of the dietary fiber they feed on. Our increasing exposure to antibiotics and antimicrobial compounds may be harming our beneficial bugs as well. These depletions could affect kids from the moment they enter the world: Because babies are seeded with their mothers' microbiota as they pass through the birth canal, they may be inheriting a less diverse microbiome than did previous generations. And the rising rate of caesarian deliveries may be further depriving our children of the bugs they need.
On expert suggests two measures worth a try: increasing consumption of fiber, and reducing use of antimicrobial agents, from antibacterial cleaners to antibiotics.
So which culprit is most responsible for the food allergy upsurge? "The illnesses that we're measuring are complex," says Sicherer. "There are multiple genetic inputs, which interact with one another, and there are multiple environmental inputs, which interact with each other and with the genes. There's not one single thing that's causing this. It's a conglomeration."
What Parents Can Do
For anyone hoping to reduce their child's or their own odds of developing a food allergy (rates of adult onset are also increasing), the current state of science offers few guideposts. As with many other areas of health research, it's hard to know when the data is solid enough to warrant a particular course of action. A case in point: the American Academy of Pediatrics once recommended that children at risk of allergy to peanuts (as evidenced by family history, other food allergies, or eczema) wait to eat them until age three; now, the AAP advises those parents to start their babies at four months, citing epidemiological evidence that early exposure may prevent peanut allergies.
And it's all too easy for a layperson to draw mistaken conclusions from media coverage of such research—inferring, for instance, that taking commercially available probiotics might have a protective effect. Unfortunately, says Nagler, none of those products even contain the relevant kind of bacteria.
Although, as a research scientist, she refrains from giving medical advice, Nagler does suggest (based on a large body of academic literature) that two measures are worth a try: increasing consumption of fiber, and reducing use of antimicrobial agents, from antibacterial cleaners to antibiotics. Yet she acknowledges that it's not always possible to avoid the suspected risk factors for food allergies. Sometimes an antibiotic is a lifesaving necessity, for example—and it's tough to avoid exposure to such drugs altogether, due to their use in animal feed and their consequent presence in many foods and in the water supply. If these chemicals are contributing to the food allergy epidemic, protecting ourselves will require action from farmers, doctors, manufacturers, and policymakers.
My family's experience illustrates the limits of healthy lifestyle choices in mitigating allergy risk. My daughter and son were born without C-sections; both were breastfed as well, receiving maximum microbial seeding from their mother. As a family, we eat exemplary diets, and no one could describe our home as excessively clean. Yet one child can't taste nuts, sesame, or buckwheat without becoming dangerously ill. "You can do everything right and still have allergies," says Ian A. Myles, a staff clinician at the National Institute of Allergy and Infectious Diseases. "You can do everything wrong and not have allergies. The two groups overlap."
The Latest Science Shows Promise
But while preventing all food allergies is clearly unrealistic, researchers are making remarkable progress in developing better treatments—therapies that, instead of combating symptoms after they've started (like epinephrine or antihistamines), aim to make patients less sensitive to allergens in the first place. One promising approach is oral immunotherapy (OIT), in which patients consume small but slowly increasing amounts of an allergen, gradually reducing their sensitivity. A study published last year in the New England Journal of Medicine showed that an experimental OIT called AR101, consisting of a standardized peanut powder mixed into food, enabled 67 percent of participants to tolerate a dose equivalent to two peanut kernels—a potential lifesaver if they were accidentally exposed to the real thing.
Because OIT itself can trigger troublesome reactions in some patients, however, it's not for everyone. Another experimental treatment, sublingual immunotherapy (SLIT) uses an allergen solution or dissolving tablet placed beneath the tongue; although its results are less robust than OIT's, it seems to generate milder side effects. Epicutaneous immunotherapy (EPIT) avoids the mouth entirely, using a technology similar to a nicotine patch to deliver allergens through the skin. Researchers are also exploring the use of medications known as biologics, aiming to speed up the action of immunotherapies by suppressing IgE or targeting other immune-system molecules.
These findings suggest that drugs based on microbial metabolites could help protect vulnerable individuals against a wide range of allergies.
One downside of the immunotherapy approach is that in most cases the allergen must be taken indefinitely to maintain desensitization. To provide a potentially permanent fix, scientists are working on vaccines that use DNA or peptides (protein fragments) from allergens to reset patients' immune systems.
Nagler is attacking the problem from a different angle—one that starts with the microbiome. In a recent study, a follow-up to her peanut-allergy investigation, she and her colleagues found that Clostridia bacteria protect mice against milk allergy as well; they also identified a particular species responsible, known as Anaerostipes caccae. The bugs, the team determined, produce a short-chain fatty acid called butyrate, which modulates many immune activities crucial to maintaining a well-sealed gut.
These findings suggest that drugs based on microbial metabolites could help protect vulnerable individuals against a wide range of allergies. Nagler has launched a company, ClostraBio, to develop biotherapeutics based on this notion; she expects its first product, using synthetic butyrate, to be ready for clinical trials within the next two years.
My daughter could well be a candidate for such a medication. Sam, now 15, is a vibrant, resilient kid who handles her allergies with confidence and humor. Thanks to vigilance and luck (on her part as well as her parents'), she hasn't had another food-related ER visit in more than a decade; she's never had to use her Epi-Pen. Still, she says, she would welcome the arrival of a pill that could reduce the danger. "I've learned how to watch out for myself," she says. "But it would be nice not to have to be so careful."