Corn syrup and other refined foods may be much to blame for the huge increase in type-2 diabetes in the United States over the past few decades, U.S. researchers said on Thursday.
A study of nearly 100 years of data on what Americans eat show a huge increase in processed carbohydrates, especially corn syrup, and a large drop in the amount of fiber from whole grains, fruits and vegetables.
It parallels a spike in the number of cases of type-2 diabetes, caused by the body’s increasing inability to properly metabolize sugars.
“We are seeing this big jump in the number of calories,” that people are eating, Dr. Lee Gross, a family physician at the Inter-Medic Medical Group in North Port, Florida, who led the study, said in a telephone interview.
“We tried to break down where are these calories coming from? We have heard everyone debating is it because of fat, is it because of carbohydrate and it is not really clear,” Gross added.
“This shows the increase in the past 20 years is almost exclusively carbohydrates and certainly corn syrup consumption has increased dramatically.”
Gross said he was not “picking on the corn syrup industry,” but added, “It is hard to ignore the fact that 20 percent of our carbohydrates are coming from corn syrup -- 10 percent of our total calories.”
An estimated 16 million Americans have type-2 diabetes, the sixth leading cause of death overall. And many studies have linked a high intake of refined carbohydrates and other foods with a high “glycemic index” with the development of diabetes.
Insulin spikes
Foods with a high glycemic index cause a spike in insulin production. Many experts agree that, over time, repeatedly eating foods in this pattern can cause insulin resistance, which in turn leads to diabetes.
Writing in the American Journal of Clinical Nutrition, Gross and colleagues said they used data from the U.S. Department of Agriculture and Centers for Disease Control and Prevention to show that people have eaten about the same amount of carbohydrates a day on average -- 500 grams -- since 1909.
But instead of whole grains and vegetables, people are getting more and more of those carbs in the form of processed grains and sugars -- most of all, in corn syrup, they said.
Gross, with colleagues at the Harvard School of Public Health and the CDC, found that starting in 1980, people started consuming steadily more calories, with an average increase in total calories of 500 calories a day.
“Specifically, 428 calories (nearly 80 percent of the increase in total energy) came from carbohydrates,” they wrote.
Gross said people are probably not eating all those 500 calories. Some could be wasted. “It’s an estimate. It’s hard to interpret,” he said.
But the trend was clear.
“During the same period, the prevalence of type-2 diabetes increased by 47 percent and the prevalence of obesity increased by 80 percent,” they wrote.
Audrae Erickson, President of the Corn Refiners Association, called the report misleading.
“Diabetes rates are rising in many countries around the world that use little or no high fructose corn syrup in foods and beverages, which supports findings by the Centers for Disease Control and the American Diabetes Association that the primary causes of diabetes are obesity, advancing age and heredity,” she said in a statement.
