As the days start to cool and the wind stirs the leaves, nothing feels cozier than snuggling up with a blanket and a mug of hot chocolate. Wait, did we say hot chocolate? We meant to say a pumpkin spice latte (PSL), which has become the quintessential fall beverage. If you’ve noticed an extra long line in your local Starbucks lately, it’s probably thanks to the seasonal treat.

“This was the 14th year we celebrated the return of fall and shared PSL with our customers,” says Reggie Borges, global corporate communications manager at Starbucks. “First introduced in 2003, PSL has become Starbucks most popular seasonal beverage ever.”

And loyal fans can be really, really enthusiastic. Etsy shop owner Veronica Clayborn is so besotted with PSLs, she designs and retails mugs inspired by them.

“My thought is that pumpkin spice is synonymous with fall,” says Clayborn. “I totally and completely love the smell of pumpkin spice. It feels familiar and comfortable like an old friend — a best friend. I was once asked to describe my obsession with pumpkin spice. My response: Pumpkin Spice is my BFF. So, I designed a mug based on that quote.”

More than 200 million PSLs have sold at Starbucks since the beverage debuted.

She drinks between five and seven PSLs a week, supporting her habit with the influx of Starbucks gift cards that come rolling in on her birthday, which is in September as good luck would have it. She actually used to drink between 10 and 14 PSLs a week but cut down after going through her own form of “PSL rehab.”

Clayborn may be a bit on the extreme end of the PSL-devotee spectrum, but she’s hardly alone in her cravings. Starbucks’ Borges says that more than 200 million PSLs have sold at Starbucks since the beverage debuted. That’s a lot of pumpkin spice, which prompts the question, why exactly do we love it so much? What happens to our brains when we get that creamy, nutmeg, clove and cinnamon-tinged rush?

It All Comes Down To Smell

The interesting thing about pumpkin spice is that we tend not only to be obsessed with how it tastes, but we’re obsessed with how it makes us feel on an emotional level.

“There is something so inherently fall about pumpkin spice,” says Sa'iyda Shabazz in Los Angeles. “Even when it's 100 degrees outside, it can make you think of cool weather, the leaves changing colors and [wearing] boots.”

For Cindy pumpkin spice is “full of nostalgia.” Based in Guatemala but raised in the U.S, she finds it to be reminiscent of “the smell of home when I was a child” and of “leaves rustling and the deep South where I grew up.”

Smell anatomically has a more direct connection to classical memory regions in the brain.

That’s some pretty intense imagery and feelings for a beverage to induce. Dr. John McGann, a sensory neuroscientist at Rutgers department of psychology, explains that it all has to do with the olfactory system, aka our sense of smell, which is complex to say the least.

“Most of what we refer to colloquially as taste is actually smell,” says McGann. “About 70 percent of our [perception] of taste is retronasal smell and then maybe 25 percent of it is true taste: salty, bitter, sweet. But there also additional components: the feeling of creaminess, which really contributes to a perception of flavor [and entails] your sense of touch. Then there’s an additional sense of pungency, [as in] the burning feeling of pepper from hot wings. That’s your trigeminal system. So, your brain is putting all of these things together.”

And your brain is also assembling memories and emotions. In this way, smell is totally unique from all other senses, which pass first through the thalamus, a sort of relay station of the brain. Instead smell goes straight to the olfactory bulb.

“From there it goes to the amygdala, which controls emotion, and to the hippocampal formation, the entorhinal cortex,” explains McGann. “Smell anatomically has a more direct connection to classical memory regions in the brain.”

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A Portal To Happier Times

McGann recalls a famous scene in Proust’s masterpiece, “Remembrance Of Things Past”, where the narrator eats a madeleine cookie and it’s as if he’s literally transported back to another time and place. On some level, the same thing may happen to us when we drink pumpkin spice lattes. What makes it so widely relatable a phenomenon is because the drink includes spices like cinnamon, clove and nutmeg that we are more exposed to during the holidays, particularly in western culture. Furthermore, the smell of pumpkin is associated with Thanksgiving and autumnal harvest — a historically prosperous time of year.

Food chemists have clearly hit an olfactory jackpot with PSL, which is why it’s more than just a fad. Like chocolate, it's looking like it will likely become a long-time seasonal staple.

“The pumpkin spice blend is not a trend as it [evokes] natural emotion of human beings,” says Thierry Muret, Godiva’s executive chef chocolatier, adding that “of course” Godiva jumped on the bandwagon with a pumpkin spice truffle. “It’s about making people happy and connecting them to moments: the changing of the season, of being warm under the covers, but also the memory of spending enjoyable time with family and friends.”

Sugar, Sugar, Sugar!

It’s rather moving to consider just how emotionally rousing the act of drinking a beverage can be, but before we cry into our lattes over the beauty of it all, let’s also remember that PSLs are loaded with sugar. We may be waltzing down memory lane, but we’re also getting a serious sugar rush.

“Unfortunately, the beverage contains a dangerous amount of sugar — up to 50 grams,” says Dr. Taz Bhatia, a board-certified integrative medicine physician and wellness expert and the author of Super Woman RX. “The American Heart Association recommends no more than 37 grams of sugar a day for men, and 25 for women. This one drink is double the amount of sugar women should intake in one day.”

Dr. Taz adds that increased sugar in your diet can lead to elevated blood sugar, elevated triglycerides and high blood pressure.

It’s really important to keep your PSL habit in check, but if you are going to splurge, Leah Groppo, a clinical dietician at Stanford Health Care suggests that you opt for a tall (the smallest at Starbucks); though it still has more than the recommended sugar amount, it’s a bit less outrageous.

“Also ask for fewer pumps of the syrup if you can,” says Groppo. “And don’t be tempted by the baked goods laid out in the beautiful glass cabinetry. If you need to eat something with it, pick something with protein like a string cheese.”

And when you indulge, be sure to limit added sugars for the rest of the day, since you've likely capped out your daily quota. Groppo also suggests you make it “an active day,” so that you put the sugar to use, and that you up the healthy proteins and vegetables in subsequent meals, because with all that sugar, you’ve also consumed a ton of carbs. One small glimmer of autumn cheer: The whipped cream isn’t going to do much more harm in terms of sugar, so allow yourself to go all out on occasion and really enjoy the beverage — and then make adjustments elsewhere in your diet.

“The whipped cream isn’t the killer, it’s the mix,” says Groppo. “Normally whipped cream in an aerosol canister is okay because it’s so aerated that it can actually be pretty low sugar and low calorie.”

If you’re prone to high blood sugar or have diabetes or any other condition where you really can’t afford the splurge, but so badly crave the pumpkin spice taste, you have options.

“Buy pumpkin spice seasoning,” recommends Groppo. “You can also put cinnamon on hot black coffee or with almond milk, or do pumpkin puree smoothies, which can have less sugar and more fiber. There are also pumpkin spice yogurts which have lower sugar.”

Have We Taken Pumpkin Spice Too Far?

We may be hooked on PSLs (even if they’re far from healthy), but one tends to wonder, are we taking this pumpkin spice fad a bit too far? (There is now everything from pumpkin spice Oreos to pumpkin spice dog shampoo on shelves.) I actually quite enjoy my collection of pumpkin spice candles, and I love me a PSL now and then, but do I want everything in my life to taste and smell and like a fragrant pie? I don’t — and part of me is looking forward to spring just so I can walk through a grocery store without being assailed by pumpkin spice versions of this and that.

Social media was the accelerant that fueled the contagion of pumpkin spice lattes.

I’m not the only one feeling the overload. Godiva’s Muret notes that manufacturers are “capitalizing on pumpkin spice, but not putting the effort into what it means,” while Dr. McGann chimes, “it seems like it’s becoming a joke at this point.”

Such is the result of not only a genius beverage, but a genius marketing campaign on behalf of Starbucks, who, by hyping the limited time nature of the drink, are advertising not just a product, but the fleeting essence of a season. And the brand has been successful on pushing this message of ephemeral delight on social media. PSL lover and mug maker Clayborn says that she “stalks” Starbuck’s Twitter, @TheRealPSL, which is devoted to everything PSL, and whips up fun memes on a regular basis. And Clayborn is just one of 115,000 followers. Do a search for #pumpkinspice on Instagram and you’ll see over 1.2 million results.

“Social media was the accelerant that fueled the contagion of PSLs,” says Marcus Collins, lecturer of marketing at the University of Michigan’s Ross School of Business. “The observability of consumption, thanks to these connected technologies, have created the perceived ubiquity of PSLs, which creates intrigue and influences mimicry among our networks of people.”

This viral influence has aptly moved all sorts of manufacturers to get in on the sensation.

“It’s a natural thing that derivative works will arise around an idea,” adds Collins. “We see it in music, in fashion and other behaviors. Much like any other diffusion of behavior within a population, there will eventually be a new thing for the fall that will drive the decline of pumpkin spiced themed products. However, with pumpkin spice products growing in sales year over year, there is no sign of slowing at the moment.”

So for now, we can all keep sipping all the feels this season — until we're forced to reign in our sugar intake and coffee budget come winter.

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