High fructose corn syrup (HFCS), the sweetener that’s ubiquitous in sodas, processed snacks, and junk foods, may tinker with the brain in ways that, unlike glucose, may actually encourage us to overeat. The problem is that after downing a soft drink containing fructose, the brain may not register that we’re full, according to a study published in the January 2, 2013 issue of the Journal of the American Medical Association.
For the investigation, scientists used MRI scans to visualize and compare blood flow in the brain after their subjects – 20 young, normal-weight men and women – drank beverages containing HFCS and, a few weeks later, one containing glucose.
Scans showed that drinking the glucose-sweetened beverages turns off brain areas that stimulate the desire for food, but this didn’t happen when the drinks contained HFCS.
The study was small and didn’t prove that HFCS contributes to obesity although increases in obesity have paralleled the use of HFCS. More studies will be necessary to confirm the negative effects HFCS has on the brain.