The calendar still reads "August" and the temperatures throughout most of the United States feel decidedly like summer, but that has not stopped restaurants from introducing their fall menus.
At Krispy Kreme, Tim Hortons and 7-Eleven, pumpkin spice season is already here – with more to come on the horizon.
But where does this love affair with pumpkin spice come from? Why is America so crazy about it — and why is it seemingly in everything?
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The answer, Boston-based Matt Johnson, PhD, might be in our brains.
"With each passing fall season, pumpkin spice becomes more and more iconic," Johnson told Fox News Digital via email. "The flavor and scent [have] become inextricably tied to memories of fall, holidays and comforting traditions, creating an emotional connection that brands capitalize on."
"The general flavor profile of pumpkin spice is rooted in the seasonal foods we typically enjoy during autumn," said Johnson, a professor at Hult International Business School and host of the neuroscience of marketing blog.
It's "brilliant marketing" that has resulted in the flavor profile becoming a "cultural icon, deeply embedded in our collective experience of fall."
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Something called the "scarcity effect" is also partially behind pumpkin spice's popularity, Johnson noted.
"Pumpkin spice is only available for a limited time, making it feel special," he said. "This seasonal exclusivity drives demand, leading brands to infuse everything from lattes to candles with the scent."
He added, "Our gustatory system is highly impressionable, and the associations between this flavor and the season create a powerful emotional response."
Convenience chain 7-Eleven released its fall offerings on Aug. 1, according to a news release published on its website. In addition to pumpkin-spiced coffee drinks, five 7-Eleven stores had a limited-time "Pumpkin Spice Slurpee" drink, the company said.
The beverage "is unlike anything fall flavor fans have tasted before, with the flavor of pumpkin and cinnamon spice swirled together in the form of a refreshing, ice-cold Slurpee drink," its website said.
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Krispy Kreme launched its fall menu, featuring a pumpkin spice-flavored doughnut and coffee beverage, on Aug. 12, noting that fan demand was partially why the seasonal menu was making a rather un-seasonable debut.
"It's August, and we're all ready for pumpkin spice, somehow. So, we're bringing back the classics you're craving," Dave Skena, global chief brand officer at Krispy Kreme, said in its news release.
The website for Tim Hortons boasts that "pumpkin season starts early," and its app users now have "early access" to pumpkin-flavored beverages.
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While Starbucks has yet to release its fall menu for its restaurants, Starbucks pumpkin spice coffee and creamers have been on grocery store shelves since the start of August, the chain's website said.
And fan websites have noted that historical trends suggest Dunkin' will be releasing its fall menu within days.
Nostalgia, too, also plays a role.
Despite the relative newness of the pumpkin spice craze – the pumpkin spice latte at Starbucks debuted in 2003 – the drink has become "something of a national comfort beverage," Johnson said.
"Fall flavors like pumpkin spice evoke strong reactions because they tap into nostalgia and the brain's reward system," he said, similar to the way a person turns to comfort foods.
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The nature of autumn, with the shrinking days and colder temperatures, helps drive these feelings of nostalgia and comfort, Johnson said.
"As days grow shorter and colder, familiar scents and tastes offer comfort, triggering positive memories of past autumns," he said. "Pumpkin spice, for instance, is often associated with cozy moments like Thanksgiving gatherings and warm drinks."
The familiarity of pumpkin spice flavors leads to a "predictable pleasure," said Johnson, which makes consuming something pumpkin spice-flavored "emotionally satisfying."
"This combination of nostalgia and sensory gratification is why people are so enthusiastic about fall flavors despite the season's darker mood," he said.
"With each sip, we're not just tasting pumpkin spice. We're savoring the essence of autumn itself, making it a sensory celebration of the season," Johnson added.
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"It's as if we are tasting the fall season itself with each sip."