There are new Pop Tarts, and they are Limited Edition. I know this because it says “Limited Edition” in bold red lettering inside a yellow banner that circumscribes the box. For an unspecified but finite amount of time only, Pop Tarts are available in a seasonal palette and flavor: pumpkin pie.

Pumpkin-pie Pop Tarts sound disgusting, it’s true. But I may not have another opportunity to buy them. If panicked urgency isn’t enough to make me buy them, there’s also the appeal of authenticity: They are“made with real nutmeg, cinnamon, and clove.” Just like grandma used to make her Limited Edition Pop Tarts.

Advertisers know that we consumers of food believe that “real” means healthy. To some degree, it used to. “Real” meant whole foods not far removed from the ground, which meant they were less likely to contain added sugar and salt, more likely to contain fiber and deliver nutrients. But “real” has been repurposed by advertising and technophobia, to the point that it’s largely meaningless, if not misleading. Though it does still accomplish the ultimate goal in marketing, to make people feel things.

Kellogg’s spent $32 million last year in advertising Pop Tarts alone. Coca-Cola spent $269 million advertising its flagship product (Coca-Cola). Pepsi spent $150 million just to advertise the brightly colored sugar-water that is Gatorade. It's the sugar water for people who do sports. These are numbers that Marion Nestle, professor of nutrition, food studies, and public health, highlighted in a lecture at New York University on Thursday night. “Think about what that money could do for education, for social welfare,” Nestle implored. “But that money is spent getting people to buy sugar.”

Effective advertising, Nestle reminds us, is supposed to be subliminal. You aren’t supposed to feel it. In the case of these Pop Tarts, I am meant to feel urgency and trust. The marketing should stop short of saying exactly what the box means to imply: Buy me now. I am wholesome, and I will make you look great. I will make you happy. Yes, happiness exists, and it is I, the Pop Tart.

On Thursday night on the campus of NYU’s Steinhardt School, I listened as four of the eminent professors of food-centric sciences of our time ostensibly told their audience “Why We Eat What We Eat.” The event was in honor of the school’s 125th anniversary. In 1890, it became the first school of pedagogy in the country, predicated on the idea that teachers should have some kind of training. The idea remains unfulfilled in much of the field of nutrition today, where so many people claim expertise.

But Nestle has the bona fides, billed by the university as “one of the world's most powerful foodies.” Her latest book, Soda Politics, will be published October 5. She was joined on stage by Krishnendu Ray, the chair of her department at NYU, Gordon Shepherd, a distinguished professor of neurobiology at Yale, and Steven Shapin, a distinguished professor of the history of science at Harvard.

Half of our plates should be covered in fruits and vegetables, according to federal nutrition recommendations, Nestle reminded us. She then pulled up a slide showing the money that the government actually gave out from 2008 to 2012: Less than one half of one percent of all agricultural subsidies went to production of fruits and vegetables. Four times as much went to tobacco.

Despite the fact that fruits and vegetables are the only foods that experts encourage us to eat with abandon, all fruits, vegetables, and nuts are considered “specialty crops” by the U.S. Department of Agriculture. Less than five percent of land planted with food goes to growing fruits and vegetables. More than 50 percent goes to growing soybeans and corn, to feed animals and refine into sugar.

“If you go into a supermarket, you see that most of what’s lined up there is to sell sugar,” Shepherd noted. Some of that we pay for directly, and some of it we pay for in taxes that subsidize its production. Shepherd’s neurobiological research has been integral to understanding how the brain processes what we call flavor, which gets lost in the process. It’s a sensation that he says most people wrongly believe is driven by taste, only because taste happens in our mouths, and food goes in our mouths.

Rather, flavor is largely a matter of smell. Shepherd explained the critical role of something called retronasal olfaction, meaning that exhaling air pushes air over the food in a person’s mouth and up into their nasal cavity. From there, sensory signals spread throughout the neocortex, to areas associated with emotion, motivation, language, and more. All of this underlies future cravings. But none of this would happen if you held your breath or nose while eating. You taste almost nothing. You look childish.

The sensation of flavor is created when retronasal olfaction is augmented by taste and the other senses: The mechanical senses of texture and motion from the tongue, the appearance of food, and the sounds of crunching or sipping. Our brains evolved to what they are because of the flavors that drove us to consume certain foods, and the increasing capacity of our brains to appreciate flavors led us in agricultural directions that shaped politics, economics, and ecology. Still few of us, he believes, appreciate flavor.

“Very few of us ever taste real, flavorful food,” Shepherd said, disconcerted. He speaks with the empiricism of a neurobiologist rather than the elitism of a foodie, so it’s not off-putting. “Unless you go to a market in the summer and find produce that was grown locally and not flown in from Chile, you have never tasted things at their full flavor.” And he means it as a potentially consequential public-health issue. If people had easy access to that kind of flavor, how many people might choose to eat healthier foods and then, you know, become healthy.

When Shapin, whose expertise is in the sociology of knowledge itself, took his turn at the lectern, he apologized for his lack of Powerpoint. “I have no pictures for you. I couldn’t think of any pictures," he said, in a stern tone that felt almost like a scolding. He has the moustache and countenance of Sam Elliott, if Sam Elliott lived in Boston, did all of his family's cooking, and wrote a book called A Social History of Truth. “I couldn’t think of any bullet points,” he grumbled extemporaneously. “And that’s not for lack of imagination. ‘Why do we eat what we eat?’ To respect that question is to respect its staggering complexity. The question presupposes choice. For most of human history, the overwhelming majority of people did not have choice. At present, very many people do not have choice.”

That lack of choice is what led Nestle, who entered academia with a Ph.D. in molecular biology, to become a professor of sociology (among her other titles). It became clear to her that the most urgent barriers to a just American food experience were not matters of metabolism, but of access and inequality, of the politics of lobbying, of the language of marketing, and of the deeply funded and subsidized, strategically crafted emotional appeal of Pop Tarts.