Foods that appear to be nutritious could actually be destroying your brainpower. The culprit? A common ingredient slipped into many "healthy" foods, including baby food, applesauce, and oatmeal, a breakfast favorite. Researchers at UCLA found that ingesting foods and drinks containing the ingredient high-fructose corn syrup for just six weeks caused troubling changes in brain function. "Our findings illustrate that what you eat affects how you think," says Fernando Gomez-Pinilla, PhD, a professor of neurosurgery and integrative biology and physiology at UCLA. "Eating a high-fructose diet over the long term alters your brain's ability to learn and remember information."
While high-fructose corn syrup is rampant in soda and candy products, it also hides out in some seemingly innocuous items like bread, juices, ketchup, and instant oatmeal. (Previous studies have found high-fructose corn syrup is sometimes contaminated with mercury.) Most often associated with obesity and diabetes, this latest study, appearing in the Journal of Physiology, shows this industrial food ingredient can harm the brain, too.
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This could be leading to an all-out American brain drain, given that the average citizen downs 40 pounds of the ingredient every year.
To find out how high-fructose corn syrup affects brain function, researchers studied two groups of rats: One group downed high-fructose corn syrup in water for six weeks; another dined on high-fructose corn syrup but also received doses of brain-protecting omega-3 fatty acids.
Before their high-fructose corn syrup diet began, the rats were all trained to navigate a maze. After eating the sweetener for six weeks, researchers put the rats to the maze test again. The animals that didn't receive the omega-3 brain protection were slower and experienced problems with brain signaling, which disrupts critical skills like memory and thinking. Researchers also witnessed signs of insulin resistance in the group without omega-3s; this could hamper normal energy processing, which could impact thoughts, emotions, memory, and learning, according to Gomez-Pinilla. "Our study shows that a high-fructose diet harms the brain as well as the body," he adds. "This is something new."
3 Rules for Avoiding a High-Fructose Corn Syrup-Derived Brain
#1: Eat organic. If you don't feel like reading fine-print ingredient labels every time you reach for a product in the supermarket, just look for the organic seal. High-fructose corn syrup and many other harmful food additives are banned. And whatever you do, don't ditch real fruit, which contains a natural form of fructose, not the dangerous processed type. "We're not talking about naturally occurring fructose in fruits, which also contain important antioxidants," explains Gomez-Pinilla. "We're concerned about high-fructose corn syrup that is added to manufactured food products as a sweetener and preservative."
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#2: Find safer sweet treats. Gomez-Pinilla, a native of Chile and an exercise enthusiast who practices what he preaches, advises people to keep fructose intake to a minimum and swap sugary desserts for fresh berries and Greek yogurt, which he keeps within arm's reach in a small refrigerator in his office. An occasional bar of dark chocolate that hasn't been processed with a lot of extra sweetener is fine, too, he adds.
#3: Eat for brain protection. Be sure to eat foods containing naturally robust levels of omega-3 fatty acids, especially if you'll be indulging in food containing high-fructose corn syrup. Omega-3–rich foods include eggs from pastured hens, wild-caught Alaskan salmon, flaxseed, and walnuts. DHA, the type of omega-3 that comes from omega-3–rich animal products, helps protect against damage to brain synapses. These synapses are critical to tasks like memory and learning—the very functions that high-fructose corn syrup damages.