Can Lab-Grown Meat Save Our Broken Food System - and Prevent Killing of Billions of Animals?
The following is an excerpt from the new book Unnaturally Delicious: How Science and Technology are Serving Up Super Foods to Save the World by Jayson Lusk (St. Martin's Press, 2016)
On August 5, 2013, Mark Post went out to grab a hamburger. This was no Big Mac from a drive-through. Post bit into his $325,000 burger in front of an invitation-only crowd of journalists, chefs, and food enthusiasts in the heart of London. The strangest part wasn’t the cost or the crowd, but the meat. Post, a professor of vascular physiology at Maastricht University in the Netherlands who has spent time on faculty at Harvard Medical School and is an expert on skeletal muscles, grew the burger himself. Not from a cow on his farm, mind you, but from a bovine stem cell in a petri dish in his lab. Post’s research, partially funded by Sergey Brin, one of Google’s cofounders, has the potential to upend conventional wisdom about the environmental, animal welfare, and health effects of meat eating.
Ironically, I met Post at a meeting of some of the world’s largest hog producers. Without any apparent trepidation, he took the stage in front of several hundred hog farmers and meat processors and told them their business was causing undue animal suffering and environmental harm.
Post’s concerns are widely reflected in popular culture. For example, the 2014 documentary film Cowspiracy argues that meat eating is the single greatest environmental threat to the planet. Bill Maher, comedian and host of an HBO talk show bearing his name, has written, “But when it comes to bad for the environment, nothing—literally—compares with eating meat. . . . If you care about the planet, it’s actually better to eat a salad in a Hummer than a cheeseburger in a Prius.” He’s not alone in his concern. The cookbook author and New York Times writer Mark Bittman has asserted that our modern livestock production practices are leading to a “holocaust of a different kind.” The historian James McWilliams, in an op-ed piece in The New York Times, perhaps summed up the prevailing view best when he wrote:
“The industrial production of animal products is nasty business. From Mad Cow, E. coli and salmonella to soil erosion, manure runoff and pink slime, factory farming is the epitome of a broken food system.” McWilliams argues that modern livestock agriculture is so damaging that the only moral solution is to give up eating meat entirely.
These statements contain a bit of hyperbole, and I’ll take issue with a few of the claims later, but for now it is important to note that these ideas are influential and have moved beyond popular discourse to affect public policy. For example, the 2015 Dietary Guidelines Advisory Committee released its recommendations to the secretaries of the U.S. Department of Health and Human Services and U.S. Department of Agriculture. The preliminary dietary guidelines have dropped meat from the list of recommended foods, and the committee has, based on both health and sustainability arguments, recommended a more plant-based diet and less meat consumption. The change in stance affects not only the information disseminated to the public but also what foods the national school lunch programs use and the flow of federal dollars to competing research priorities.
Post has taken a different tack—one that has sometimes put him at odds with vegetarian advocacy groups. Rather than selling the “tax meat” tote bags that People for the Ethical Treatment of Animals (PETA) uses to raise money or cajoling and chastising people for eating meat, he recognizes that most people like to eat a good steak. Yes, some people live a healthy, vegetarian lifestyle for their entire lives. But that’s not the norm. Only about 5 percent of the U.S. population is vegetarian or vegan, and 84 percent of the people who are vegetarians and vegans eventually go back to eating meat. It seems that we are biologically wired to want to eat meat. That bite of filet mignon is a protein-packed, nutrient-dense morsel of tasty goodness. Anthropology shows that humans have probably eaten meat since the beginning, and some biologists believe that meat consumption, and the ability to increase nutrient content through cooking meat, played a role in increasing our brain size, making us into the species we are today.
No matter the news on health and environmental outcomes, most people are still going to want to eat a burger. Indeed, one of the first things people at the lower end of the socioeconomic spectrum in developing countries want to do when they get a little more money in their pockets is to eat more meat. Meat eating is positively correlated with income. Although meat is often more expensive than grains or veggies, when we can afford it, we want it.
Given that people want to eat meat, what can we do to make a difference? Why not try to make sure that the meat we do eat has as little environmental impact as possible?
One way to reduce the environmental impact of meat eating is to make livestock more productive. That is the route relentlessly pursued by the livestock industries. And it has worked. Beef production in the United States has a far lower carbon footprint than in other parts of the world, precisely because we use more intensive operations, and, despite the allure of grass-fed beef, feedlot operations for fattening cattle with grain have smaller carbon footprints. One study in the Journal of Animal Science calculated that from 1977 to 2007, the carbon emissions associated with producing a fixed quantity of beef in the United States fell 16 percent, water use fell 12 percent, and the amount of manure generated dropped 19 percent. Increased efficiencies have led to similar reductions in carbon emissions and resource use for hogs, poultry, and dairy. For example, one report from the pork industry suggests that the environmental impact and natural resources associated with hog production fell by 50 percent during the fifty years between 1959 and 2009.
Unfortunately, some of these efficiency gains have been realized by using technologies that many consumers dislike. For example, use of growth promoters, such as added hormones, in beef cattle have significantly lowered carbon emissions, water use, and animal waste. But, despite clear evidence of the safety of these products, consumers are disturbed by the thought. Likewise, the increased efficiency of pork production has occurred in part because hogs have been moved indoors and sows are housed, for a majority of their lives, in gestation stalls that, while preventing aggression and facilitating individualized feeding and care, pre- vent the mamma hogs from turning around.
Post is imagining an altogether different sort of technological innovation, one that yields the bacon and burgers we love without the hog or cow. All animals have stem cells living in their muscles. These cells are capable of regenerating muscle cells for the animal. They’re also capable of creating muscle cells outside the animal. The trick is to harvest stem cells from the muscle of a live cow or pig and turn them loose in the right environment in a lab. Stem cells proliferate quickly. A single stem cell can generate 100 trillion cells of meat. So, from a small number of donor animals (many millions fewer than currently exist to satisfy our appetites), we can ultimately get our burgers, chops, and chicken tenders without harm to the cows, pigs, or chickens. We no longer have to kill the geese to get the golden eggs.
Once in the lab and given a suitable environment, the stem cells naturally form into muscles. But the formation of muscle cells doesn’t mean we have something ready to eat. We all have muscles, but they vary in shape and size. I’ve got a couple of scrawny biceps, whereas Arnold Schwarzenegger has guns. How did Schwarzenegger's arms get so big? No doubt genetics played a role, but he’s also spent many, many more hours in the gym than I. Building protein and muscle size requires exercise. Post and his team attach the muscle cells to each other and to a proverbial petri dish in a way that creates exercise-like tension. The result is muscle fiber (each fiber contains about 1.5 million cells). Once these muscle fibers develop, about ten thousand are harvested to create a burger.
This isn’t a soybean patty crafted to look like a hamburger. It is a real meat burger produced by the same cells doing the work in a real cow. Still, when Post talked about his new burger, he said it was a bit dry. That shouldn’t be too surprising because it was 100 percent lean and had no fat. To really mimic the taste of a burger, fat and connective tissue are needed. These fats could come from vegetable sources (like canola or corn oil) or Post might just grow it too. He’s now got a few petri dishes of animal fat growing to try to add a little flavor to his next lab-grown lunch. Fat stem cells from livestock can be used in much the same way as muscle stem cells, although they’re a bit trickier to deal with because they’re more flexible than muscle stem cells and must be coaxed into producing only desirable kinds of fat.
Perhaps surprisingly, not all vegetarians and animal advocacy groups are supporters of Post’s work. For one, they don’t like it that stem cells must be extracted from a live animal. But if the choice is between the emissions of carbon by a few thousand animals and many millions of animals that leave waste in waterways and gobble up valuable resources that we humans might use, the answer seems clear. But these folks also point out that lab-grown meat isn’t a free lunch. The stem cells have to eat something to grow. Right now the cells grow in a medium that relies on animal-based serum. However, Post and others are devising non- animal–based feed stock for the muscles.
More broadly, this line of argument—that meat production (inside the lab or out) is wasteful because it requires feed resources that humans might use—is misplaced. To see this, it is useful to consider a thought experiment—an imaginary story that might help us get to the bottom of things.
Imagine a biologist on an excursion to the Amazon to look for new plant species. She comes across a grass she’s never before seen and brings it home to her lab. She finds that the grass grows exceedingly well in greenhouses with the right fertilizer and soil, and she immediately moves to field trials. She also notices that the grass produces a seed that is durable, storable, and extraordinarily calorie dense. The scientist immediately recognizes the potential for the newly discovered plant to meet the dietary demands of a growing world population.
But there is a problem. Lab analysis reveals that the seeds are, alas, toxic to humans. Despite the setback, the scientist doesn’t give up. She toils away year after year until she creates a machine that can convert the seeds into a food that is not only safe for humans to consume but that is incredibly delicious to eat. There are a few downsides. For every five calories that go into the machine, only one comes out. In addition, the machine uses water, runs on electricity, burns fossil fuels, and creates carbon emissions.
Should the scientist be condemned for her work? Or hailed as a genius for finding a plant that can inexpensively produce calories, and then creating a machine that can turn those calories into something people really want to eat? Maybe another way to think about it is to ask whether the scientist’s new food can compete against other foods in the marketplace—despite its inefficiencies (which will make the price higher than it otherwise would be). Are consumers willing to pay the higher price for this new food?
