Study: Countries That Use More High Fructose Corn Syrup Have More Diabetes

The 20 percent increase in type 2 diabetes is independent of total sugar consumption and obesity.

Andrees Latif/Reuters

PROBLEM: Is high fructose corn syrup the harbinger of the health apocalypse? A review of the debate in the American Journal of Clinical Nutrition rejects HFCS as a causative factor of obesity, arguing that the processed stuff, though scary-sounding, "is not meaningfully different in composition or metabolism from other fructose-glucose sweeteners like sucrose, honey, and fruit juice concentrates." But those in the anti-HFCS camp aren't convinced, and would insist there's still plenty to be wary of -- they point to diabetes as another public health concern whose rise parallels the increased prevalence of HFCS in foods and beverages.

METHODOLOGY: "It's very hard to study the effects of high fructose corn syrup on overall health," explained lead author Michael Goran, Professor of Preventive Medicine, Physiology and Biophysics, and Pediatrics at USC, "Because we simply don't know how much we're consuming, even in the U.S." So he and fellow researchers at USC and Oxford took a broader, population-based approach, looking at estimates for the prevalence of type 2 diabetes -- culled from two independent sources -- as related to the availability of HFCS in 43 countries. They also looked at the total availability of sugar and calories, along with estimated rates of obesity and impaired glucose tolerance, and each country's GDP.

RESULTS: "All indicators of diabetes were higher in countries that use HFCS as compared to those that do not," with type 2 diabetes occurring in 8 percent of the population. Countries that don't use HFCS had a diabetes rate of 6.7 percent -- a 20 percent different in prevalence. These results held when adjusted for BMI averages and economic climate, and were independent of total sugar intake and obesity levels.

Where HFCS is found has a lot to do with trade and agricultural policies. Per capita consumption of HFCS was highest in the US, where we consume 55 pounds of the sweetener per year. The U.S. was followed by Hungary, with the markedly lower rate of 46 pounds per capita, along with Canada, Slovakia, Bulgaria, Belgium, Argentina, Korea, Japan and Mexico.

The countries where no HFCS at all is used include India, Ireland, Sweden, Austria, Uruguay, and Lithuania. France, China, Australia, and the UK all use less than one pound per capita.

CONCLUSION: High fructose corn syrup, "beyond the effects of sugar itself and of BMI," is associated with an increase in the risk of type 2 diabetes.

IMPLICATIONS: That there was no variation in total sugar and calorie consumption or obesity levels between the countries, Goran explained, "suggests there's something additional about high fructose corn syrup that has a strong effect on diabetes." The researchers hypothesize that this could be due to its slightly higher levels of fructose than regular sugar (the ratio of fructose to glucose is 55:45 instead of 50:50), drawing on previous findings that indicate there are "unique detrimental properties of fructose that pose a risk to metabolic health."

"There's lots of other different factors contributing to global diabetes," Goran continued. "We're just saying that high fructose corn syrup is one."

The full study, "High Fructose Corn Syrup and Diabetes Prevalence: A Global Perspective" is published in the journal Global Public Health.