There are lots of possible explanations for why Americans are becoming more and more obese: you could blame it on a lack of exercise, the explosion of fast-food outlets and processed food, and even the Internet because people sit in front of screens for way too long instead of moving around.
But a number of scientists blame a common ingredient called high-fructose corn syrup. In the past 30 years, which roughly coincides with the development of the obesity epidemic, it has become a common ingredient in a wide range of foods, including everything from breads to soups to lunch meats. Basically, it's corn syrup in which some of the glucose has been converted to fructose – which is a scientific way of saying it's really sweet and makes food tastier.
But does it make us fatter? Not surprisingly, the Corn Refiners Association, a trade group, says it's no worse than traditional table sugar. For more on their view, click here. Some other studies (some of which were financed by corn growers) have also suggested that the connection between high fructose syrup and obesity is unclear, including an American Medical Association report that urged more research on the subject.
Now scientists at the Oregon Health & Science University say that the brain reacts differently to fructose compared to glucose. The research, which will appear in the journal Diabetes, Obesity and Metabolism, involved using functional MRI to see how the brain reacted to fructose, glucose and a saline solution. The scientists found that the part of the brain involved in regulating food intake behaved very differently to fructose and glucose.
These scientists think their results make a good case against fructose and they recommend that consumers monitor their intake. That's good advice – no matter what the final verdict on fructose.