Authors: Michael Moss
As they tasted and swallowed, Rolls watched the machinery register their brain’s response. As expected, the saliva generated no evident stimulus. No surprises with the sugar solution, either: It provoked a vivid response, with the images generated by the machine depicting the brain’s electrical activity as patches of bright yellow. But the shock came when his subjects got hold of the fat: Their brain circuitry lit up just as brightly for the fat as it did for the sugar. Moreover, the images showed that this brain activity occurred precisely where neuroscientists would expect to see this activity. The sugar and fat stimulated areas of the brain associated with hunger and thirst, but they also lit up the reward center, which generates the feelings of pleasure.
“Fat and sugar both produce strong reward effects in the brain,” Rolls said when I asked him which was more potent, sugar or fat. It’s a toss-up.
In recent years, some of the world’s largest food manufacturers have been conducting brain research of their own to assess the depths of fat’s allure. Unilever alone invested $30 million on a twenty-person team that
used brain imaging and other advanced neurological tools to study the sensory powers of food, including fat. The scientist who led the Unilever team until recently, Francis McGlone,
described its operations as a freewheeling exploration of a rapidly expanding corner of science, where $3 million brain scanning devices and other neurological testing can reveal more about consumer likes and dislikes than companies could ever glean from focus groups. Unilever has a massive lineup of health and beauty aids, from Dove to Alberto VO5, as well as packaged food, from Ben & Jerry’s to Knorr, and McGlone roamed across the whole range of products hunting for ways to improve upon them. For the most part, he sought to discover precisely what made certain groups so alluring. Like many specialists in basic science who go to work for food manufacturers, he brought with him the dispassionate language of researchers who see consumers as experimental subjects.
“I went there to build a research focus that looked at the reward-based systems that underpin their business,” he told me. “Their business was basically all feeding and grooming, involving 6.7 billion people or, in my view, 6.7 billion primates. And I saw feeding and grooming as very stereotypical human behaviors. There is not a lot to be gained from asking people
why
they like something, because they don’t bloody know. These are very low-level processes that drive these fundamental behaviors, and I’d gotten into imaging because it’s a good way to sort of bypass the mouth, if you like, so you can see just what the neural processes are underpinning a behavior.”
McGlone didn’t have to bother talking to his subjects; he could peer into their brains. And the discoveries made by his team underscored the complex and varied ways in which processed food can be made ultra-alluring. They explored all five of the basic senses. To examine the
role that odor plays in foods, for example, they let their subjects smell a glass of Hershey’s Chocolate Cookies ’n’ Cream Milkshake, and found this excited the brain’s pleasure zones just as if they were tasting the drink. To study
the power of hearing, one of the team’s scientists, Charles Spence, amplified the sound made by potato chips when they were eaten. This study—which won an Ig Nobel, the prize awarded to research that is brilliant but
quirky—showed that the louder the noise, the deeper the allure; the noisiest chips were rated by test subjects as the freshest and crispiest. McGlone has studied how the mere sight of food can excite the brain.
Being the world’s largest ice cream maker, with brands like Breyer’s and Ben & Jerry’s, Unilever itself got quite excited by his work on how the brain responds to the silky smooth fat and sugar in ice cream. This project started in 2005 when
McGlone had a conversation with the company’s research director for consumer insight. They determined there might be a substantial commercial payoff if he could establish that ice cream made people happy—through scientific methods, that is. So McGlone put eight graduate students in an MRI and then scanned their brains as an assistant tipped a spoon of vanilla ice cream onto their lips, letting it melt into their mouths. McGlone is a bit sheepish about the scientific weight of this experiment: He told me that he would never seek to publish the results, since there were too few subjects and
too many variables to qualify as solid, peer-reviewed science. But the resulting images—which show the brain’s pleasure centers lighting up as the subjects tasted the Unilever ice cream—thrilled the marketing arm of the company. “This is the first time that we’ve been able to show that ice cream makes you happy,” a Unilever vice president, Don Darling, told a food industry publication.
“Just one spoonful of Carte D’Or lights up the happy zones of the brain in clinical trials.” Unilever released the results, generating a flurry of publicity for the company and its ice cream in news reports throughout the world including the U.S. media with the slogan: “Ice Cream Makes You Happy—It’s Official!”
Even without these brain studies, however, food manufacturers have long understood the power of fat to make their products more attractive. The industry’s reliance on the stuff runs so deep that suppliers of fat, like Cargill, hold training seminars. Based near Minneapolis,
Cargill is one of the world’s largest privately owned companies and a dominant provider of ingredients to food manufacturers. It sells seventeen types of sweeteners, forty types of salt, and twenty-one oils and shortenings, from coconut for spraying on snacks to palm for candies to peanut for deep-fat frying. In a
recent presentation to food manufacturers who purchase its fats, a Cargill manager empathized when a customer asked for advice in reducing the amount of fat that snacks absorb in being fried.
Lessening the amount of fat in processed food—like reducing the sugar or salt—is no simple matter to the manufacturers. They can’t allow this to diminish the taste or texture, or they will lose sales. Nor can they let a reduction in fat cause their production costs to rise too high, or they will lose profits. The X factor is often how much more money consumers are willing to spend for a healthier product. In this case, the Cargill manager pointed out, fiddling with the fat used for frying had serious implications for the bottom line of its customers. Sure, they could cut down on the fat in their foods. All they had to do was turn up the temperature of the oil. But the higher the temperature, the less often the oil can be reused before going bad, which would send the food manufacturers running back to Cargill more often for fresh oil. “It doesn’t work all of the time, but the hotter the oil, the less absorption of the snack, in principle,” the manager, Dan Lampert, said. “We like it because the hotter the oil, the more oil we sell. Just kidding.”
I
n one respect, fat is considerably less powerful than the other two keystones of processed foods, sugar and salt. Fat’s public image has always been horrid.
Sugar—at least until the surge in obesity in the 1980s—has been something that manufacturers have eagerly touted in their foods with a long list of charming euphemisms. The words
honeyed, sugarcoated, sweet, syrupy
, and
candied
were effective marketing tools in attracting consumers. More broadly, the word
sweet
was used to connote anything good, innocent, or attractive. Likewise, until blood pressure rates in America went up in the 1980s, salt had a favorable image, too, helped along by colloquialisms like, “the salt of the earth.” Picture in your mind a hot pretzel with big white
crystals of salt on top; your brain is probably, at this very moment, sending you signals of pleasure.
Now picture that same pretzel dipped in oil. That is not such a positive image, is it? There are some exceptions to this, to be sure. (What’s a lobster without a dish of hot melted butter?) By and large, however, and for as long as anyone in the food industry can remember, fat has been saddled with more than its share of negativity. (No kid’s grandmother will say to them with a pucker: “Give me some fat.”) For starters, its lingo is deeply unappealing. If a food isn’t “fatty,” it’s “greasy” or “oily” or “heavy.” Even worse, fat in food is equated with fat on the body, and there is ample justification for this. Fat is an energy colossus. It packs 9 calories into each gram, more than twice the caloric load of either sugar or protein. Surveys have shown that grocery shoppers who stop to read nutrition labels look first and foremost at the fat content of foods. This has led to the proliferation of products that claim to have less fat or lower fat, and it has spurred a host of marketing tricks the industry uses to make it seem like they have cut back. Take milk, for instance. Through the 1960s, sales of milk plunged as it bore the brunt of public concerns about fat, both in terms of its calories and its links to heart disease. At the same time, however, the dairy industry figured out a way to soften this blow to their business by putting the phrases “low-fat” and “2 percent” on milk in which a little of the fat had been removed. The popularity of this defatted milk grew so fast that it now outsells all other types of milk, including skim, which has no fat at all. But there is a marketing scheme at work in this: The “2 percent” labeling may lead to you to believe that 98 percent of the fat is removed, but in truth the fat content of whole milk is only a tad higher, at 3 percent.
Consumer groups who urge people to drink 1 percent or nonfat milk have fought unsuccessfully over the years to have the 2 percent claim barred as deceptive.
While fat’s PR has suffered greatly, the food industry has privately treated fat as a cherished friend, one whose quirks and mysterious ways it has labored hard to understand and cultivate. At the General Foods research center in Tarrytown, New York, fat became the lifelong obsession of
a Polish-born scientist named Alina Szczesniak, who retired in 1986. One of her more lasting contributions stemmed from her realization that fat, in one respect, is not about taste at all. Nor did people have to like the sight of oil pooling atop their pizza to be enthralled by what happens inside their mouths. Szczesniak was the first to grasp that fat is about feel, or texture, and that it is an enormously powerful force in processed food that often flies under our radar, drawing us in without the blaring horns that a dose of sugar or salt will set off in the mouth.
Part of Szczesniak’s job involved evaluating new versions of products like Jell-O and imitation whipped cream toppings. She used ordinary citizens as guinea pigs, sitting them down in a room with some samples to taste and a rating chart to
describe the textures. As she developed these tests, Szczesniak accumulated a
long list of terms to describe the feel of fatty foods, including
smooth, firm, bouncy, wiggly, disappears, slippery, gummy, melts, moist, wet
, and
warm
. Her tasting system is still used today by manufacturers, and these textural attributes became known as the “mouthfeel” of fat. There is strong neurological science backing her up on this notion that fat is as much a feeling as it is a taste. We now know that we feel fat through a nerve called the trigeminal. This critical part of our anatomy hovers above and behind the mouth near the brain with tentacles that extract tactile information from the lips, gums, teeth, and jaw, which it then conveys to the brain. The trigeminal nerve is how we distinguish between sandy and smooth, and why grit in a salad causes us to cringe. When it comes to fat, it detects the enthralling crunch in fried chicken, the velvet in melting chocolate and premium ice cream, the creaminess in cheese. And it delivers these sensations with plenty of muscle, a recent brain study by Nestlé shows.
Nestlé, which has picked up on fat research where General Foods left off, has good reason to want to deepen its understanding of fat. Back when it was founded in the mid-1800s, the company had one product to worry about: milk chocolate. But today, Nestlé is a $100 billion global giant with a portfolio of processed foods and drinks that rely on fat, from Häagen-Dazs ice cream to Kit Kat bars to DiGiorno frozen pizzas, which have up to
8 grams of saturated fat in a single serving—half of the recommended daily maximum for adults.
*
The indispensability of fat to Nestlé’s balance sheets becomes all the more evident to the company whenever it tries to cut back. In the early 1980s, one of its food scientists, Steve Witherly, was trying to save the company money by lessening the amount of cheese in a sauce. He used substituting chemicals designed to impart a cheese-like tang, but the fat in cheese, he realized, provided more than just flavor. It gave the sauce its silky, rich texture, the mouthfeel that people wanted—and that was something no chemical could replicate.
“We were always trying to make it cheaper,” he told me, “but people could always detect if we started messing around with the cheese. It’s the texture of cheese sauce people go crazy for. That gooey, sticky mouthfeel, kind of like a peanut buttery mouthfeel that really made people want to be on my taste panels. Something about the cheese made people go nuts.”
At Nestlé’s research and development center near Geneva, Switzerland, the scientists include a German-trained biophysicist named Johannes Le Coutre who is currently using some of the same brain-mapping science that academic centers like Oxford employ. His tools include electroencephalography, or EEG, in which a net of electrodes is affixed to the head to explore how the brain responds to various stimuli. In 2008, he wired up fifteen adults to an EEG machine and
showed them pictures of foods that were either low or high in fat. At first, he wanted to see if their brains would recognize the difference, and they did. But then he made another noteworthy discovery. He timed the signals given off by the food pictures, and found that they raced to the brain in a mere 200 milliseconds. The brain was identifying fat with incredible speed. In his quest to learn more, Le Coutre rounded up fifty of his colleagues in industry and academia and asked them to help produce an “all known facts” compendium on fat. Published in 2010 with 609 pages, the resulting book,
Fat Detection: Taste
,
Texture, and Post Ingestive Effects
, serves as a roadmap for companies looking to harness the power of fat in their food and drink.
“Why is fat so tasty?” Le Coutre asks in the introduction. “Why do we crave it, and what is the impact of dietary fat on health and disease?”