The whole truth about high-fructose corn syrup

This ad has been making waves lately. It is one of three commercials that the Corn Refiners Association debuted last month to "change the conversation about high-fructose corn syrup."

In the ad, one mother begins to lecture another about the dangers of high-fructose corn syrup in the "red juice" (as such products were always called in my house) that is being served at a children's party. The second mother turns the tables and catches the other speechless about what exactly is wrong with the corn-derived sweetener, and finally delivers the Corn Refiners' message, "It's made from corn, doesn't have artificial ingredients, and like sugar, it's fine in moderation."

Let's take the Corn Refiners' points one by one:

1. "It's made from corn." True. High-fructose corn syrup is indeed made from corn. But you won't get the same beneficial nutrients in it that you would from eating an ear of corn.
2. "Doesn't have artificial ingredients." Partly true. The claim about artificial ingredients is a tricky one, since high-fructose corn syrup is processed using artificial agents. The U.S. Food and Drug Administration has stated that if the final product has come in contact with synthetic agent glutaraldehyde, then it cannot be called "natural," which they define as meaning no artificial or synthetic ingredients were added. But if the manufacturer uses the artificial agent in its production, and it does not come in contact with the corn starch, it can be considered a natural product. So it's possible that some high-fructose corn syrups may be able to claim "no artificial ingredients," according to the FDA, while others would not be permitted the phrase. It's distinctions like these that lead Consumers Union to consider the "natural" label not meaningful.
3. "Like sugar, it's fine in moderation." True. Most foods are fine in moderation. It's too much or too little that causes problems. However, some would probably argue that with high-fructose corn syrup in so many products, to truly enjoy it in moderation you'd probably be better off leaving the "red juice" on the shelf.

So what has happened to "the conversation about high-fructose corn syrup" in the first place that led its manufacturers to want to rehabilitate its reputation?

In 2004, researchers from the Louisiana State University and University of North Carolina published a paper that theorized that high-fructose corn syrup in beverages could play a role in the obesity epidemic. They looked at the correlation between the 1,000 percent increase in high-fructose corn syrup consumption between 1970 and 1990, and a correlating rise in obesity rates. Because of the way the body metabolizes fructose from beverages, the researchers argued, it may play a role in the obesity epidemic.

High fructose corn syrup has become one of the boogeymen of processed foods. The Corn Refiners Association is probably right in noting that it has no known special risk compared to table sugar. While it has been implicated in a rise of Type 2 diabetes, obesity, and other health problems, high-fructose corn syrup and white sugar are almost identical chemically; each is about half fructose and half glucose.

The association between high-fructose corn syrup and obesity may reflect that we consume so much of it. Nearly all sugars add empty calories to our diets. And because high fructose corn syrup is the main sweetener in most soft drinks and a common one in other foods (including breakfast cereals, salad dressings, cheese spreads, yogurts, jams, and peanut butter, among others), many people may just consume more of it than other sugars. But that doesn't mean that there's definitely no added risk from fructose in general. A new study of rats by researchers from the University of Florida suggests that a diet high in fructose may lead the body to develop a resistance to a protein called leptin, which helps control appetite. More research is needed to fully understand the relationship.

We do know that Americans can stand to cut back on sugar. According to the U.S. Department of Agriculture, the average American should consume no more than about 40 grams of added sugars a day–added sugars don't include those that occur naturally in fruit and other foods. But the average American consumed more than three times that in 2000. People who want to limit their overall sugar intake would be wise to cut down on products that have added sugars, including high-fructose corn syrup, listed among the first several ingredients, which are listed by proportional weight on the label. But be aware, sugars can hide under a variety of names (subscribers only). Replacing soft drinks with water has been shown to reduce total calories consumed by kids. For more on picking a fruit juice, see our story from May. We also recently covered sugary cereals here and here.

—Kevin McCarthy, associate editor

Read more on how obesity affects your daily life and see our Treatment Ratings (subscribers only) for the evidence on lifestyle changes and surgeries for losing weight.