That Sugar Rush Is All In Your Head

iStock.com/egal
iStock.com/egal

We've all heard of the "sugar rush." It's a vision that prompts parents and even teachers to snatch candy away from kids, fearing they'll soon be bouncing off the walls, wired and hyperactive. It’s a myth American culture has clung to for decades—and these days, it’s not just a kid thing. Adults are wary of sugar, too. Some of this fear is warranted—diabetes, the obesity epidemic—but the truth is, sugar doesn't cause hyperactivity. Its impact on the body isn’t an up-and-down thing. The science is clear: There is no "sugar rush.”

To find out how and why the myth started, we need to go back to well before the first World War—then pay a visit to the 1970s.

Our Complicated Relationship With Sugar

According to cultural historian Samira Kawash, America has had a long, complex, love-hate relationship with sugar. In Candy: A Century of Panic and Pleasure, Kawash traces the turn from candy-as-treat to candy-as-food in the early 20th century. At that time, the dietary recommendations from scientists included a mix of carbohydrates, proteins, and fats, with sugar as essential for energy.

Not everyone was on board: The temperance movement, for example, pushed the idea that sugar caused an intoxication similar to alcohol, making candy-eaters sluggish, loopy, and overstimulated. In 1907, the chief of the Philadelphia Bureau of Health estimated that the "appetite" for candy and alcohol were "one and the same," Kawash writes. On the flip side, other scientists suggested that sugar from candy could stave off cravings for alcohol—a suggestion that candymakers then used in their advertisements.

While the debate about sugar as an energy source raged in America, militaries around the world were also exploring sugar as energy for soldiers. In 1898, the Prussian war office became the first to commission a study on the sweet stuff—with promising results: "Sugar in small doses is well-adapted to help men to perform extraordinary muscular labor," early researchers wrote. German military experiments introduced candy and chocolate cakes as fortification for the troops, and the U.S. military added sugary foods to soldiers' diets soon after. When American soldiers returned from World War I, they craved sweets, which "propelled an enormous boom" of candy sales that has lasted to this day, Kawash wrote on her blog, The Candy Professor. American advertisers framed candy as a quick, easy source of energy for busy adults during their workday.

As artificial sweeteners moved into kitchens in the 1950s, candymakers struggled to make their products appeal to women who were watching their waistlines. One industry group, Sugar Information Inc., produced a tiny "Memo to Dieters" pamphlet in 1954 designed to fit inside chocolate boxes. "Sugar before meals raises your blood sugar level and reduces your appetite," it claimed. But by the 1970s, the sugar-positivity heyday had started to wane.

The Origins of the Sugar Rush Myth

The idea that sugar causes hyperactivity gained traction in the early 1970s, when more attention was being paid to how diet might affect behavior. One of the major figures studying the possible connection between diet and behavior was an allergist named Benjamin Feingold, who hypothesized that certain food additives, including dyes and artificial flavorings, might lead to hyperactivity. He formalized this into a popular—yet controversial—elimination diet program. Though certain sugary foods were banned from the program for containing dyes and flavorings, sugar itself was never formally prohibited. Still, thanks in part of the Feingold diet, sugar started to become the poster child for diet and hyperactivity.

It wasn't until the late 1980s that serious doubts about sugar's connection to hyperactivity began to be raised by scientists. As FDA historian Suzanne White Junod wrote in 2003 [PDF], the 1988 Surgeon General's Report on Nutrition and Health concluded that "alleged links between sugar consumption and hyperactivity/attention deficit disorders in children had not been scientifically supported." Despite "mothers' mantra of no sweets before dinner," she noted, "more serious allegations of adverse pediatric consequences … have not withstood scientific scrutiny."

A 1994 paper found that aspartame—an artificial sweetener that had also been accused of inducing hyperactivity in children—had no effect on 15 children with ADHD, even though they had consumed 10 times more than the typical amount.

A year later, the Journal of the American Medical Association published a meta-analysis of the effect of sugar on children's behavior and cognition. It examined data from 23 studies that were conducted under controlled conditions: In every study, some children were given sugar, and others were given an artificial sweetener placebo like aspartame. Neither researchers nor children knew who received the real thing. The studies recruited neurotypical children, kids with ADHD, and a group who were "sensitive" to sugar, according to their parents.

The analysis found that "sugar does not affect the behavior or cognitive performance of children." (The authors did note that “a small effect of sugar or effects on subsets of children cannot be ruled out.”)

"So far, all the well-controlled scientific studies examining the relationship between sugar and behavior in children have not been able to demonstrate it," Mark Wolraich, an emeritus professor of pediatrics at the University of Oklahoma Health Sciences Center who has worked with children with ADHD for more than 30 years and the co-author of that 1995 paper, tells Mental Floss.

Yet the myth that consuming sugar causes hyperactivity hasn’t really gone away. One major reason is the placebo effect, which can have powerful results. The idea that you or your children might feel a "sugar rush" from too much candy isn't unlike the boost you hope to feel from an energy drink or a meal replacement shake or bar (which can contain several teaspoons of sugar). The same is true for parents who claim that their kids seem hyperactive at a party. Peer pressure and excitement seem to be to blame—not sugar.

"The strong belief of parents [in sugar's effects on children's behavior] may be due to expectancy and common association," Wolraich wrote in the JAMA paper.

It works the other way, too: Some parents say they've noticed a difference in their kids' behavior once they take out most sugars from their diets. This strategy, like the Feingold diet, continues to attract interest and followers because believing it works has an impact on whether it actually works or not.

Correlation, Causation, and Caffeine

Which isn't to say there are absolutely no links between sugar consumption and poor health outcomes. A 2006 paper found that drinking a lot of sugary soft drinks was associated with mental health issues, including hyperactivity, but the study's design relied on self-reported questionnaires that were filled out by more than 5000 10th-graders in Oslo, Norway. The authors also noted that caffeine is common in colas, which might have a confounding effect.

In another study, conducted by University of Vermont professor of economics Sara Solnick and Harvard health policy professor David Hemenway, the researchers investigated the so-called "Twinkie defense," in which sugar is said to contribute to an "altered state of mind." (The phrase Twinkie defense comes from the 1979 trial of Dan White for killing San Francisco city district supervisor Harvey Milk and Mayor George Moscone. His lawyers argued that White had "diminished capacity and was unable to premeditate his crime," as evidenced in part by his sudden adoption of a junk-food diet in the months before the murders. White was convicted of voluntary manslaughter.)

In their survey of nearly 1900 Boston public high schoolers, Solnick and Hemenway found "a significant and strong association between soft drinks and violence." Adolescents who drank more than five cans of soft drinks per week—nearly 30 percent of the group—were significantly more likely to have carried a weapon.

But Solnick tells Mental Floss the study isn't evidence of a "sugar rush."

"Even if sugar did cause aggression—which we did not prove—we have no way of knowing whether the effect is immediate (and perhaps short-lived) as the phrase 'sugar rush' implies, or whether it’s a longer-term process," she says. Sugar could, for example, increase irritability, which might sometimes flare up into aggression—but not as an immediate reaction to consuming sugar.

Harvard researchers are looking into the long-term effects of sugar using data from Project Viva, a large observational study of pregnant women, mothers, and their children. A 2018 paper in the American Journal of Preventive Medicine studied more than 1200 mother-child pairs from Project Viva, assessing mothers' self-reported diets during pregnancy as well as their children's health during early childhood.

"Sugar consumption, especially from [sugar-sweetened beverages], during pregnancy and childhood, and maternal diet soda consumption may adversely impact child cognition,” the authors concluded, though they noted that other factors could explain the association.

“This study design can look at relationships, but it cannot determine cause and effect,” says Wolraich, who was not involved in the study. "It is equally possible that parents of children with lower cognition are likely to cause a greater consumption of sugar or diet drinks, or that there is a third factor that influences cognition and consumption.”

The Science of the Sugar Crash

Though the evidence against the sugar rush is strong, a "sugar crash" is real—but typically it only affects people with diabetes.

According to the National Institute of Diabetes and Digestive and Kidney Diseases, low blood sugar—or hypoglycemia—is a serious medical condition. When a lot of sugar enters the bloodstream, it can spike the blood sugar level, causing fluctuation, instability, and eventually a crash—which is called reactive hypoglycemia. If a diabetic's blood sugar levels are too low, a number of symptoms—including shakiness, fatigue, weakness, and more—can follow. Severe hypoglycemia can lead to seizures and even coma.

For most of us, though, it's rare. Endocrinologist Dr. Natasa Janicic-Kahric told The Washington Post that "about 5 percent of Americans experience sugar crash."

You're more likely to experience it if you do a tough workout on an empty stomach. "If one exercises vigorously and doesn't have sufficient intake to supplement their use of calories, they can get lightheaded," Wolraich says. "But in most cases, the body is good at regulating a person's needs."

So what you're attributing to sugar—the highs and the lows—is probably all in your head.

Could Game of Thrones's Dragons Really Fly? We Asked Some Experts

HBO
HBO

Game of Thrones is a show that requires a serious suspension of disbelief. It exists in a universe where the dead can rise from their graves, humans can see through the eyes of animals, anyone can travel between Dragonstone and Eastwatch at or near the speed of light, and Jon Snow can hold an unbroken frown for seven straight seasons.

Still, as we anticipate the premiere of Game of Thrones's eighth and final season on April 14—and as we remember cowering each time Drogon hovered in midair to pour a throatful of flame over one of Daenerys Targaryen’s enemies in last season's big-budget battles—we started to wonder: Could a beast that big really maneuver through the air like that? Fortunately, two scientists who have dedicated their lives to studying flying creatures agreed to clear that up for us.

Kevin McGowan, a Cornell ornithologist who specializes in crows, says there’s one major problem with dragon flight: physics. “They’re just so damn big,” he says. “Way too big to ever get off the ground.”

For comparison, there's the albatross, which weighs around 25 pounds and needs a 10-foot wingspan in order to heave itself into the air. And birds don’t scale up easily. McGowan says that as a bird gets heavier, its wingspan has to grow exponentially to keep up: “If you need a 10 foot wingspan for a 25-pound bird, what would you need for a 2000-pound dragon?” (Last season, one eagle-eyed engineer estimated that Drogon weighed around three tons and flew with a wingspan under 60 feet—and the dragons are even bigger now.)

In the real world, bird species generally stay small to avoid having to grow their wings exponentially. Those that do grow large wings, like the albatross, can travel long distances—but pay the price in maneuverability. Birds with smaller wings can maneuver in tighter spaces, but have to expend much more energy to stay aloft. “Birds make a lot of compromises to fly,” McGowan says, “and dragons just aren’t doing that.”

Still, there is some hope for letting our dragon-sized fantasies take flight. Michael Habib, a paleontologist and assistant professor of clinical integrative anatomical sciences at the University of Southern California's Keck School of Medicine, studies the flight mechanics of extinct animals, including giant pterosaurs once thought to be too big to get off the ground. He also works with film studios like Disney, Marvel, and Lucasfilm to design believable flying monsters like griffins, hippogriffs, and pegasi. There are three tricks, he says, for plausibly scaling up fantasy flying creatures.

First, you want to give them the right wing type. Like modern day bats, pterosaurs—which lived from 228 to 66 million years ago—had membrane wings, made of skin stretched over a series of elongated fingers. These are good for slow, maneuverable flight, and they don’t have to be as large compared to the body as a bird’s feather wings. Habib tells Mental Floss that a dragon with a good pair of wings would be able to sustain flight easily once it was in the air—but it could only get there “if it came with a catapult for takeoff.”

Second, a dragon needs to have the right skeletal structure. Their bones should be strong enough to withstand the massive mechanical forces involved in flight without getting too heavy. Hollow bones are best; they're actually stronger than a very dense bone with a similar mass. Habib explains that’s because the bone’s ability to withstand the strain of flight depends on its diameter—the wider it is, the more force it can take. A hollow, air-filled bone can be much wider than a dense bone full of marrow, and it will still weigh less than the dense bone.

Third, and most importantly, a dragon needs to have as much power available for takeoff as possible. Habib says that almost every animal that takes flight, from birds to flying squirrels to winged snakes, gets into the air by jumping, not flapping its wings.

“What birds get stuck on is they only have two hind limbs available for jumping power,” Habib says. “Bats do better—and pterosaurs did, too—because they walk on their wings and they can jump off of all four limbs.”

That makes a big difference, especially because most of a bird’s strength is in its wings. While birds take off with less than half their bodies’ muscle power, bats and pterosaurs launch themselves with everything they’ve got. That’s what allowed the largest pterosaurs to grow into 550-pound behemoths, while the heaviest-ever flying bird—the extinct Argentavis magnificens—maxed out around 150 pounds.

The dragons in Game of Thrones do have membrane wings, and they could conceivably have hollow bones. Back in season three, WIRED reported that the show’s animators based the dragons on a cross between an eagle and a bat. (Their strenuous, flappy hovering certainly takes after fruit bats.) Although the dragons walk around on their wings like bats, they don’t seem to jump off of them during takeoff. Throughout the series, we see them dive from cliffs and glide into flight, leap off their hind legs after a running start, and sometimes just flap their wings and leave the ground.

Habib says even if a dragon followed all of his specifications, it could only grow up to about 1000 pounds without grounding itself—not several tons, like Daenerys’s children.

“They’re probably beyond the flight limit for any anatomy,” Habib concedes, “unless they’re secretly made out of carbon fiber and titanium.”

“Maybe they’re full of hot air,” suggests McGowan, “or maybe it’s just magic.”

And what would happen if a dragon got a hole in one of its membrane wings, like Viserion displays after rising from the dead in the finale of season seven? Could it still fly? "The short answer is, probably a bit, but not as well as normal," Habib says.

Bats can fly with similarly damaged wings thanks to the way wings move through air. We tend to think of them as paddles pushing the air, but wings actually pull air. Like any other fluid, air has a certain amount of intrinsic stickiness to it, so air sticks to other air. "As the wing is pulling on the air, it's flowing over and around the wing, and it will skip over the air within the wing's small gaps and imperfections just as water will jump over the holes in a storm grate," Habib says. "Obviously, the more holes you put in the wing, the more inefficient it becomes, but it will still work up to a point. If there are too many holes, it will fail."

To McGowan, though, how the dragons fly doesn't really matter: “I think all day. When I go home, I don’t want to think anymore. I can just say it’s magic. I don’t care.”

Fact-Checking Pottermore's Claim That Witches and Wizards Used Spells to 'Vanish' Their Waste Before Modern Plumbing

Warner Bros. All Rights Reserved. Harry Potter Publishing Rights/J.K.R.
Warner Bros. All Rights Reserved. Harry Potter Publishing Rights/J.K.R.

By now, you may have heard the peculiar explanation of how witches and wizards in J.K. Rowling’s universe relieved themselves before modern-day plumbing. As Entertainment Weekly reports, a section of the Pottermore website pertaining to the Chamber of Secrets entrance (which, if you recall, was in Moaning Myrtle’s bathroom) states that Hogwarts adopted plumbing in the 18th century. Before that, spells were cast to eliminate excrement—or perhaps blast it into another dimension.

“Hogwarts’ plumbing became more elaborate in the eighteenth century (this was a rare instance of wizards copying Muggles, because hitherto they simply relieved themselves wherever they stood, and vanished the evidence),” the site states in an essay by Rowling. This was initially revealed in 2015, but Pottermore's recent tweet on the subject has been causing a stink.

A lot of people aren’t satisfied with this unsavory explanation—"witches and wizards, some highly sophisticated beings who created complex magical governments and tamed the fiercest beasts, at one point just pooped themselves,” Entertainment laments—but it’s worth noting that the claim does pass a historical fact check of sorts.

According to Rowling, Hogwarts was founded in the year 990 C.E.—more than 600 years before Sir John Harington, the godson of Queen Elizabeth I and a distant relative of Game of Thrones star Kit Harington, invented the first flush toilet. Even though this technology existed in the 16th century, Harington only made two toilets: One for himself and one for his royal godmother. The first patented flush toilet didn’t arrive until 1775, thanks to a different design by watchmaker (and toilet inventor) Alexander Cummings. So the timing checks out.

Of course, people didn’t just pee themselves or pop a squat on the ground prior to working toilets, which is why so many people are baffled by Rowling’s explanation. Chamber pots and outhouses were used throughout much of human history, and members of the British ruling class had more luxurious arrangements. In the 16th century, King Henry VIII did his business atop a padded chair—covered in sheepskin, black velvet, and ribbons—with a chamber pot beneath it. However, male courtiers did sometimes do their business wherever they felt like it (palace stairwells were one popular location in France).

As for Hogwarts’ plumbing situation, it may sound like a gross and unnecessary detail, but it’s actually relevant to the story. According to a Pottermore essay penned by Rowling, the entrance to the Chamber of Secrets was nearly revealed when the school decided to build a bathroom on the site. However, a student and direct descendent of Slytherin named Corvinus Gaunt played a part in concealing its entrance—“even after newfangled plumbing had been placed on top of it.”

[h/t Entertainment Weekly]

SECTIONS

arrow
LIVE SMARTER