Your brain sees sugar as a reward. But does that mean it’s addictive?
Ppsychologist Ashley Gearhardt remembers a type 2 diabetes patient who recognized that eating soft Krispy Kreme donuts was devastatingly bad for her. Knowing that the donuts could make her illness worse didn’t stop her from driving out of her way to get a box of sweets.
“It’s clear that there is compulsion,” says Gearhardt, a professor at the University of Michigan and one of the creators of the Yale Food Addiction Scale, a self-reporting tool that allows people to find out whether they are at risk for food addiction. According to her, the inability to control a craving contributes to sugar being addictive.
Add the mood-altering effects of sugar to the argument. One Super Bowl commercial sticks in Gearhardt’s mind like no other. The 2015 ad shows actor Danny Trejo, known for his rasp and various tough guy roles, wielding an ax and complaining to iconic TV parents Carol and Mike Brady in their 1970s split-level home. After eating a Snickers bar , he transforms into a smiling and friendly Marcia, the eldest child in the blended Brady family. The ad is a cultural expression of something Gearhardt believes is real: that people can become dependent on the sweet stuff.
“We know that people eat these foods not just for the calories, but because they want to experience pleasure. You see this constantly in marketing. You are mad? Eat a Snickers. So (sugar consumption) causes mood swings.”
Since that time, the idea of sugar addiction has gained momentum, thanks in part to a much-discussed 2017 paper that suggested rats prefer sugar to cocaine. But one study doesn’t yield a consensus, and scientists have differing opinions on whether humans (or rodents) can become dependent on sugar.
There is no doubt that sugar affects our development and our brain. Giles Yeo, professor of molecular neuroendocrinology at the Medical Research Council Metabolic Diseases Unit at the University of Cambridge in England, points out that mammalian milk contains the fat and lactose sugar that babies need to grow as quickly as possible and prevent that they become prey. And we feel good when we consume sugar because our brain sees it as a reward.
But that doesn’t make it addictive, said Margaret Westwater, a postdoctoral researcher at the University of Oxford and the Yale School of Medicine. She performed one 2016 review of scientific research into sugar and addiction. She and her co-authors found no support for the idea that consuming sugar drives behavior and anxiety in the same way as drug abuse.
In a chapter in a forthcoming edition of Food and Addiction: A Comprehensive HandbookWestwater further debunks the idea that rodents will choose sugar over cocaine because the sweet substance is more addictive than the narcotic. She explains that rodents get an immediate dopamine response from the taste of sugar. Cocaine, on the other hand, takes longer to metabolize and increase dopamine release. It delivers a delayed but much more powerful hit, increasing dopamine by 120%. When cocaine or amphetamines are administered, rodent brains release dopamine up to 300% to 900% above baseline, she said. The pleasure spikes from sugar are nothing compared to the hormonal spikes that follow the use of these drugs.
That makes sugar just like anything else that “lights up the parts of the brain that make us feel good,” Yeo said, and that “including drugs, which (are) addictive, alcohol, smoking, bungee jumping, sex, and so on.” it – and sugar. So there are addictive elements to it.”
He continued, “Now I’m not trying to fool anyone with verbal gymnastics. When you talk to actual psychiatrists who work with addiction, sugar – while superficially covering aspects of addictive pathways – is not actually addictive in itself. It’s not like nicotine; it is not medicine.”
Gearhardt has a different view and believes that the definition of addiction should be revised.
“I sometimes struggle with what people use their benchmark for: how do you know if something is addictive, because it’s actually been a constant topic of discussion. In the 1970s we actually thought that cocaine was not addictive because the withdrawal syndrome did not look like (that of other) addictive drugs. What you use to make that designation is very important and should not be simply dismissed.”
She and her team propose that “very rewarding‘ and ultra-processed foods – many of which are loaded with sky-high amounts of sugar, salt and fat – are classified as addictive substances in various diagnostic frameworks. These reference guides, such as the International Classification of Diseases and the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM), help healthcare providers identify a patient’s condition and legitimize a condition.
Gearhardt’s team wants to submit their DSM application this summer. Once they do, a steering committee of psychiatric experts will do so evaluate the evidence and seek public comment, if they decide there is sufficient evidence. The committee may decide to forward an opinion to the decision-making bodies of the association for final approval.
Gearhardt thinks there is a precedent for change. She said the controversy surrounding tobacco and cigarettes was resolved based on the following criteria for addiction: that a substance triggers compulsive use and affects mood, and that both people and animals will work hard to get it. Gearhardt’s team proposes a new criterion: that a substance induces strong urges and desires.
If that proposal is approved or if at some point in the future researchers reach the now unlikely consensus that sugar is addictive, what will happen? With nicotine, cigarettes were eventually labeled with a warning, despite intentional tobacco companies misleading the public about the risks of cigarette smoking. That industry’s youth marketing was severely curtailed, which could be an option for regulating sugar since, as Yeo noted, youth may be particularly vulnerable to it.
But Emily Broad Leib, a clinical professor at Harvard Law School and director of the university’s Center for Health Law and Policy Innovation, believes systemwide solutions will be an uphill battle. This is true despite successful campaigns in several US cities (and several countries) to crack down on sugary drinks, for example by taxing soda. Sugar is cheap and often added to everything from salad dressing to bread; even people who monitor sugar intake can barely keep track of where the sweet stuff appears. Leib says food and beverage companies are benefiting from the lack of guardrails and accountability for how much they sweeten products.
“They are unfettered in the decisions they make about how much sugar to use,” Leib said, and probably as likely as big tobacco to resist efforts to change.