What Sugar Does to Your Brain
Photo by Jan Hammershaug, licensed by CC.
In the summer of 2014, registered dietitian Carole Bartolotto asked 20 of her colleagues at California-based managed-care giant Kaiser Permanente to do the unthinkable: cut out all added sugars and artificial sweeteners for two weeks. To rally her co-workers, she used the motivation tactic du jour and called it a "challenge." The instructions: No added sweeteners of any kind (including honey, stevia, Splenda). No processed foods exceeding five grams of added sugar per serving. And no more than five servings of fresh fruit daily—no fruit juice.
The results surprised Bartolotto. After two weeks, 95 percent of participants reported that sugary foods and drinks tasted sweeter or too sweet. And 75 percent said that foods such as baby carrots, even crackers, tasted sweet. "It only took two weeks for people to completely reset their palates," she says.
The first part of the experiment wasn't pretty, however. More than half the group described intense, uncomfortable sugar cravings that only subsided after three days. For another third, it took six days. Participants suffered headaches, reported that the diet modification required a "great deal of willpower," and called the first days "brutal."
Many of us have observed that sugar begets sugar. Think of the holidays, when after days of bingeing on cookies, cake, and the neighbor's homemade peppermint bark, you wake up the next morning with a great idea: scones with cream and rasberry jam for breakfast!
But Bartolotto's small survey, published in the peer-reviewed Permanente Journal, is fascinating because it's one of the few to document that we go through an actual withdrawal process when we stop eating sugar. It also confirms the informal stories shared over the years by sugar detoxers: that eliminating sugar causes low energy, depression, flulike symptoms, and mental fogginess, at least temporarily.
The evidence documenting the danger of the sweet stuff has been mounting for some time. Added sugar has long been linked to the rise in obesity and type 2 diabetes—and now we can add early death. According to a 15-year study published in the Journal of the American Medical Association: Internal Medicine, U.S. adults of all ages whose daily calorie count consisted of 17 to 21 percent added sugar (not naturally found in food) were more than a third more likely to die of heart disease than those who kept their consumption to less than 8 percent of the total—regardless of their BMIs. The mechanism is unclear, but the authors theorize it might be linked to inflammation, along with increased blood pressure and triglyceride fat levels. Other studies have linked added sugar to cancer risk, depression, and dementia.
The notion that some people can become "addicted" to food has been around since 1960, when Overeaters Anonymous was founded, based on the 12-step approach to treat alcoholism. But popular interest in the concept escalated in 2009 when Ashley Gearhardt, PhD, now an assistant professor of clinical science at the University of Michigan, helped develop what's called the Yale Food Addiction Scale. The scale is a battery of questions intended to detect signs of dependence, like "Over time, I have found that I need to eat more and more to get the feeling I want, such as reduced negative emotions or increased pleasure." Patients who struggle with at least three of the eight features of addiction qualify for the relatively new diagnosis "binge eating disorder," added to the Diagnostic and Statistical Manual of Mental Disorders in 2013.
Read the full article "What Sugar Does to Your Brain" at Harper's BAZAAR.