Pour a little sugar on it, oh yeah
Pour a little sugar on it, honey
Pour a little sugar on it, baby
Make your life so sweet, yeah, yeah, yeah
Sugar, Sugar” recorded by Ron Dante for the fictional band The Archies, (Calendar records, 1969)
I almost choked on my Little Debbie Glazed Donut Stick when I read the headline in the Wall Street Journal: “The New Science on What Ultra-Processed Food Does to Your Brain”. Wait a minute! What? Eating junk food was always about my waistline; it’s never been about my brain! This was a rent in the fabric of my universe; a shiver to my timbers; a crack in the very foundation of all that is good in the world. I still reminisce about the halcyon days of 1969 when I could blissfully follow The Archies’ dietary advice and pour a little sugar on it to make life so sweet. Adulthood resulted in only moderate tempering of that childhood bliss—as long as my pants still fit, I could indulge my sweet tooth. But now those pesky researchers are forcing a re-think of our current junk food mindset. Apparently, those ubiquitous ultra-processed foods that are oh-so-tempting and oh-so-easy to eat don’t just affect the waistline, they may also affect cognitive functions, like learning, remembering, and feeling. Too much junk food now could have two consequences: bigger waistlines and a decline in brain function. The end result might be best described in a paraphrase of Dean Wormer’s advice to Flounder in the movie Animal House: “Fat, and stupid is no way to go through life, son.”
Although we might have preconceived notions of which foods are ultra-processed, it’s worthwhile to look at how scientists define them. And it turns out, there isn’t one standard definition, but rather, multiple variations of definitions that get us to roughly the same spot. The most succinct of those definitions: ultra-processed foods are industrially produced foods that contain ingredients not commonly found in home kitchens. Ultra-processed foods are typically preparations of processed food substances (oils, fats, sugars, starches, and proteins) that contain very little whole, natural foods. The manufacturing process usually includes the addition of flavorings, colorings, emulsifiers (used to stabilize the processed food), and other cosmetic additives. Examples of ultra-processed foods include sweet and savory snacks, confectionery snacks, most breakfast cereals, ice cream, sugar-sweetened beverages, processed meats, and ready-to-eat frozen dinners.
In an interesting contrast, natural foods typically contain either carbohydrates or fat, but rarely contain both, whereas many ultra-processed foods contain high levels of both carbohydrates and fats, sometimes in nearly equal proportions. For example, a 100-gram serving of apple has 55 calories from carbohydrates and 1.5 calories from fat. A 100-gram serving of salmon has zero calories from carbohydrates and 73 calories from fat. On the other hand, a 100-gram serving (just under one cup) of Quaker Simply Granola has 270 calories from fat and 510 calories from carbohydrates. A 100-gram serving (a little over one third of a 276-gram bag) of Doritos Nacho Cheese chips has 714 calories from fat and 429 calories from carbohydrates. And if for dessert, we finish with a full-size 43-gram Hershey’s milk chocolate candy bar, we would get 340 calories from fat and 200 calories from carbohydrates.
And in a sad reflection of the deterioration of our modern American diets, ultra-processed foods now make up the majority of the calories we consume. According to the Wall Street Journal’s analysis of federal data collected from 2001 to 2018, U.S. adults and children aged one year and above get about 58 percent of their calories from ultra-processed foods. In 2018, children aged 2 to 19 years received 67 percent of their daily calories from ultra-processed foods, which was an increase from the 61 percent level calculated in 1999. The dietary decline is present in other countries as well: 57 percent of the calories consumed by British citizens, and 48 percent of the calories consumed by Canadian citizens come from ultra-processed foods.
So, what is the evidence for ultra-processed food affecting our brains? The Wall Street Journal article references a study published online December 2022, in JAMA Neurology. In that study, researchers looked at the eating habits of nearly 11,000 participants, (ages 35 to 74 years), all of whom were determined to be dementia-free at the start of the study. Participants underwent periodic cognitive tests that measured thinking skills such as memory, word recognition, and word recall. After an eight-year follow-up period, researchers found that participants younger than 60 years who ate the most ultra-processed food (approximately 20 percent or more of their daily calories) had a 28 percent faster rate of global cognitive decline compared to the group of participants who ate the least amount of ultra-processed food. And for reasons not readily explained, the negative cognitive effects of excessive intake of ultra-processed foods was not seen in the group of participants older than 60 years. The best news of the day: eating carrot sticks really does cancel out your chocolate indulgences. Researchers determined that eating a healthy diet was an effect modifier, finding that participants who generally ate a healthy diet, but also indulged in ultra-processed foods, had no statistical association at any age between the amount of daily calories from ultra-processed foods and their scores on global cognition tests.
Adding one more insult to the ultra-processed food injury is research showing that these foods may be at the root of addictive behaviors in about 14 percent of the adult population (similar to the percentage of adults exhibiting addictive behaviors with alcohol). The Yale Food Addiction Scale, developed by Ashley Gearhardt, a professor of psychology at the University of Michigan, asks people to report on which foods they associate with the most addictive behaviors, such as excessive intake, loss of control over consumption, intense cravings, and continued use despite negative consequences. They found the foods most strongly associated with these addictive behaviors are foods with high levels of refined carbohydrates and/or added fats, such as sweets and salty snacks. The addictive potential may be due to the speed with which these ultra-processed foods can deliver carbohydrates and fat to the gut, which quickly satisfies the addictive behaviors originating in the brain. Manufacturers can easily manipulate the food matrix during processing to make their foods easier and faster to consume, have greater bioavailability, allow them to affect the brain more rapidly, and ultimately, make it easier to become addicted to their products.
Let me wrap up some final pieces of take-away advice. Future research will likely uncover more detrimental effects of higher intake levels of ultra-processed foods, more far-reaching than weight gain and declining brain function, so continued caution against over-indulgence is warranted. Don’t beat yourself up for having junk food cravings or a lack of will power—it’s not a sign of personal weakness, but it could very well be a sign that the foods were manipulated during their processing to make them more irresistible to our palates. And finally, just in case you’ve succumbed to the urgent need for a chocolate fix, always keep some carrot sticks around as an emergency antidote!
