The study compared weight gain over an eight-week period in rats given access to an eight percent HFCS solution 12 hours a day; rats given access to the same solution 24 hours a day; rats given access to a ten percent sucrose solution; and the weight of rats given ordinary chow alone.
They found that those fed the12 hour-HFCS solution were the only ones to show statistically significant weight gain, even though they consumed fewer calories than those given the sucrose solution. The authors did not give a clear reason for how this could be the case, but speculated that slightly higher fructose levels in HFCS than in sucrose could be to blame.
Sucrose contains 50 percent glucose and 50 percent fructose, while the type of HFCS used in soft drinks contains 55 percent fructose and 42 percent glucose.
Psychology professor Dr Bart Hoebel said: “Some people have claimed that high-fructose corn syrup is no different than other sweeteners when it comes to weight gain and obesity, but our results make it clear that this just isn't true, at least under the conditions of our tests.”
Writing on her blog, NYU nutrition expert Marion Nestle said she was skeptical about the study. She said: “How they came to these conclusions is beyond me.”
The conclusion she drew from the study was: “So does HFCS make rats fat? Sure if you feed them too many calories altogether. Sucrose will do that, too.”
The Center for Consumer Freedom was surprised to find that it agreed with Marion Nestle, who it has described as “one of the country’s most hysterical anti-food-industry fanatics.”
“Marion Nestle has shed some perspective and analysis on this research,” the organization said in a statement.
The Corn Refiners Association has long argued that HFCS and sugar are handled in the same way by the body. Responding to the Princeton study, CRA president Audrae Erickson said: “This study unnecessarily confuses consumers about human metabolism of common sugars in the diet. A sugar is a sugar whether it comes from cane, corn, or beets…No metabolic effects have been found in studies that compare sugar and high fructose corn syrup consumption in humans.”
The Princeton study can be accessed here.
Fears about HFCS were raised in 2004, when an article was published in the American Journal of Clinical Nutrition hypothesizing that the sweetener could be linked to rising rates of obesity. One of the article’s authors Dr Barry Popkin has since said that he was wrong to pinpoint HFCS as obesity’s major cause, but consumer concern has continued nonetheless.