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.

My take? The U.S. Agriculture Department has calculated that the average American consumes more than 40 pounds of HFCS every year. I'm concerned that this highly processed substance has disruptive effects on metabolism, in part because the body doesn't utilize fructose well, and humans have never before consumed it in such quantity. Earlier studies have documented potential problems with thinking and memory, and HFCS has well-known adverse effects on other aspects of health. Clinical studies strongly suggest it promotes obesity, metabolic syndrome, and diabetes; disturbs liver function, and elevates serum triglycerides in men. The latest study is further evidence that HFCS isn't good for us.


Robert Sherwin, et al, "Effects of Fructose vs Glucose on Regional Cerebral Blood Flow in Brain Regions Involved With Appetite and Reward Pathways", JAMA. 2013; 309(1):63-70. doi:10.1001/jama.2012.116975

Weil Lifestyle. Does High Fructose Corn Syrup Harm the Brain? July 30¸2012.