Sugar is sugar is sugar. That's what many dietitians said for years when asked about the difference between the sugars naturally contained in fruit juice and those added to, say, soda. New research at Princeton University, however, undercuts the familiar adage, showing that high-fructose corn syrup, a common ingredient in processed foods because it's cheaper and extends shelf life, has a remarkable ability to fatten rats.
Even when rats were given much lower concentrations of the commercial sweetener than are found in soda, while other rats were given higher concentrations of table sugar, the corn-syrup rats gained more weight. Not only that, but they developed a dangerous condition known in humans as metabolic syndrome, which is marked by abnormal weight gain, increases in triglyceride levels and more fat deposits around the belly. Even rats fed a high-fat diet don't consistently gain weight, psychology professor Bart Hoebel said.
And who got it right in the whole low-carb, low-fat debate? Another study, out of Stanford University, suggests that both sides did -- to some extent. Low-carb diets work best for some people based on their genetic makeup, while low-fat diets are more effective for others.
As the United States tries to find its way out of the growing trend toward obesity that threatens the nation's health, studies like these sound a warning to be careful about well-intentioned laws that seek to limit one ingredient or another as a way of trimming society's collective waistline and staving off certain diseases.