Nov. 27, 2012 -- Countries that mix high-fructose corn syrup into processed foods and soft drinks have higher rates of diabetes than countries that don’t use the sweetener, a new study shows.
In a study published in the journal Global Health, researchers compared the average availability of high-fructose corn syrup to rates of diabetes in 43 countries.
About half the countries in the study had little or no high-fructose corn syrup in their food supply. In the other 20 countries, high-fructose corn syrup in foods ranged from about a pound a year per person in Germany to about 55 pounds each year per person in the United States.
The researchers found that countries using high-fructose corn syrup had rates of diabetes that were about 20% higher than countries that didn’t mix the sweetener into foods. Those differences remained even after researchers took into account data for differences in body size, population, and wealth.
But couldn’t that mean that people in countries that used more high-fructose corn syrup were just eating more sugar or more total calories?
The researchers say no: There were no overall differences in total sugars or total calories between countries that did and didn’t use high-fructose corn syrup, suggesting that there’s an independent relationship between high-fructose corn syrup and diabetes.
“It raises a lot of questions about fructose,” says researcher Michael I. Goran, PhD, co-director of the Diabetes and Obesity Research Institute at the Keck School of Medicine at the University of Southern California, in Los Angeles. Although the study found an association, it doesn’t establish a cause/effect relationship.
The Industry Responds
Not everyone is convinced.
Audrae Erickson is president of the Corn Refiners Association, an industry group that recently petitioned the FDA to change the name corn syrup to corn sugar on ingredient lists.
“Just because an ingredient is available in a nation's diet does not mean it is uniquely the cause of a disease,” she says in a prepared statement.
“There is broad scientific consensus that table sugar and high-fructose corn syrup are nutritionally and metabolically equivalent,” Erickson says.
“It is, therefore, highly dubious ... without any human studies demonstrating a meaningful nutritional difference between high-fructose corn syrup and sugar -- to point an accusatory finger at one and not the other,” she says.
On that point, nutritionists who were not involved in the research think the corn industry is right.
Marion Nestle, PhD, MPH, professor of food, nutrition studies, and public health at New York University, says the study “is based on a questionable and highly debatable premise: that high-fructose corn syrup is significantly different in its physiological effects from sucrose, or table sugar.”
Both table sugar and high-fructose corn syrup are a mixture of two simple sugars -- fructose and glucose.
Nestle says studies show that the body responds to table sugar and high-fructose corn syrup the same way.
The bottom line, she says, is that too much of any kind of sugar isn’t healthy, no matter where it comes from.
It's More Complicated?
But Goran says the problem is more complex.
There’s some scientific evidence that the body treats fructose differently than glucose. Table sugar is about half fructose and half glucose. The percentage of fructose in high-fructose corn syrup isn’t disclosed on food labels, but it’s thought to range from 42% to 55%. But it may be even higher than that. In a study published in 2011 in the journal Obesity, Goran found the percentage of fructose in drinks sweetened with high-fructose corn syrup ranged from 47% to 65%.
“I know there’s a lot of consumer confusion about fructose: It’s a fruit sugar; it’s healthy; it’s already in sugar,” he says. But, again, it's not that simple.
Goran thinks there’s a big difference between fructose in fruit -- where it’s paired with fiber, which slows down its absorption -- and fructose that’s refined into syrup.
“There are lots of other aspects of the way fructose is handled by the body which are different than glucose that make it metabolically dangerous for the body,” he says.