The question of whether sugar is simply a treat or actually a nasty trick goes way beyond Halloween. I love Halloween. It’s not the costumes and parties and pumpkins—they’re fun, but I don’t care so much about any of that. What I love is being able to snack openly on candy corn, Necco Wafers, and Squirrel Nut Zippers without judgy looks from others. I can eat that stuff well into November and people will assume it was left over from the trick-or-treaters. But it won’t be left over. It will be from treats I bought for myself and didn’t share with the little ingrates at the door.
Since childhood, I have had an insatiable sweet tooth. I blame my parents—specifically, my father. According to scientists writing in The American Journal of Clinical Nutrition in 2019, the perception of sweetness and intake of sugar are, in part, heritable traits. My dad used to keep candy stashed all over the house, all year round: Sugar Babies in the glove box; Milk Duds behind the cushions of the couch; Tootsie Rolls in the sock drawer. I am my father’s son, and eating confectionery makes me happy.
Sugar really can improve mood, in part by soothing negative emotions. Researchers in the journal Appetite showed this in 2022, in an experiment in which participants were told something either emphatically negative (that they’re the type of person who will end up alone, and any friends they have will drift away) or entirely neutral. The participants were then offered a highly sweetened beverage. The people in the negative condition drank nearly 40 percent more of it than those in the neutral group. Apparently, a grape Fanta is just the ticket when you learn you are going to die lonely and abandoned.
Despite the fact that my love of sweets is wired into my DNA, this year my family is urging me—no, hectoring me—to defy nature and resist my Halloween bender. They claim that it is “for my own good.” I believe this is because they hate when I’m happy. Calmly, fairly, and without flying into a rage, I have promised to look further into the scientific evidence on this matter. Does candy pass the cost-benefit test?
Our attraction to sugar probably evolved from our need to find energy-dense food in a calorie-restricted environment. In the Pleistocene period, you would have needed a significant inducement to risk your life climbing a tree for a wild banana, so the brain developed a stimulus to the ventral striatum—part of the reward system—in response to sweet-tasting food.
Besides picking bananas, hunter-gatherers were no doubt stealing honey from bees for countless millennia, but humans first started consuming sugar from cane at least 10,000 years ago, when the Indigenous people of New Guinea domesticated the plant and chewed it raw. We know of Indian texts from around 400 B.C.E. that called for refined sugar in recipes for rice pudding and barley meal. From India, sugar cane spread to Greece and Rome, where one writer marveled at “a reed in India that brings forth honey without the help of bees.” Over subsequent centuries, sugar was much used for medicinal purposes (calling to mind a doctor’s advice to take two Junior Mints and call him in the morning). In 14th-century England, Geoffrey Chaucer referred to sugar (“sugre”) as an excellent gift in The Canterbury Tales.
Candy manufacturing followed the large-scale cultivation of sugarcane in the 18th century, and the first chocolate factory was established in 1765. Although sugar rapidly became the signature cash crop of the plantation slave economy in the Caribbean, the commodity was still expensive and mostly consumed by the wealthy. An anthropological review of colonial-era Maryland noted that thanks to her sugar habit, the governor’s wife, Anne Wolseley Calvert, had lost 20 teeth, and some of those remaining were “decayed down to the root stubs.” That’s a serious commitment to sweets; to oral hygiene, not so much.
As the centuries passed and agricultural methods improved, the price of sugar dropped, people got richer, and the amount of sugar consumed skyrocketed—from an average of about six pounds per person per year at the time of George Washington to 130 pounds today. Your regular American might very well start out eating their own weight in sugar every year.
Related to this heavy consumption, a common belief has taken hold that eating a lot of sugar is bad for one’s longevity. My father, who held a Ph.D. in biostatistics, would say, “This will take about 4.3 minutes off my life,” as he poured a bag of jelly beans into his mouth. (In fact, he did die quite young, at 66.) But the data on sugar and life span are not so straightforward.
In a study of Harvard male alumni, researchers writing in The BMJ found that mortality came sooner for men who never consumed candy, compared with those who did. On average, the researchers found, men who’d indulged in sweets lived almost a year longer than abstainers. This does not mean that eating more candy makes you live longer, though: Men who partook one to three times a month had the lowest mortality, but it rose with higher consumption. (The researchers didn’t even consider people like my father, who insisted that a proper breakfast includes dessert.)
Many articles have been written about how heavy consumption of sugar can adversely affect one’s physical health, leading to such complaints as tooth decay, insulin resistance, inflammation, diabetes, and fatty liver disease. Research has also shown that consuming a lot of sugar is associated with compromised hippocampal function, impaired cognition and decision making, and impairments in memory.
To which my dad would have responded, “Yeah, but what about happiness right now?” I’m not at all sure that, if given the option of living to 90 but without circus peanuts, he would have made that choice, and he had a point. The mood enhancements from sweets are real: Experiments show, for example, that eating small amounts of chocolate has an immediate positive effect—but a very short-lived one. The chocoholic’s high, researchers found, wears off after a few minutes.
One way to interpret such findings is that the emotionally driven eating of sweets is not a good strategy to improve mood. An alternative interpretation—one I prefer—is that to maintain a steady sense of well-being, one could consider eating chocolate every three minutes. (Discipline and commitment are important, after all.)
Joking aside, sugar addiction is a real issue. Sugar consumption per capita remains high, even as a majority of Americans say they are actively trying to avoid sugar. If they’re struggling to control their intake, there’s a reason for that: The long-term consumption of sugar has been demonstrated to activate the mesocorticolimbic system in both animals and humans in a way that resembles how substance dependence becomes established. In fact, one experiment has shown that rats display even more intense behavior around sugar than they do with cocaine. Another animal study has found that the withdrawal of sugar can induce a clinical state of anxiety in sucrose-bingeing subjects.
So where does all of this leave us on the sugar and well-being issue? For health and longevity, the research to date suggests that a little is fine, whereas a lot—eating sweets several times a day, for example—can lead to a wide variety of maladies and shortened life expectancy. For mood, the benefits are positive but very brief, and the cost to happiness of actual addiction and withdrawal is serious.
As for my own Halloween-candy haul, I would like to thank my family for their concern, but I judge the issue not fully settled and needing several more years, even decades, of studies to resolve. Now please leave me alone and let me get on with my research.