It seems to be working.
U.S. use of the sweetener found in most soft drinks, cereals and a range of other products dropped 11 percent between 2003 and 2008, the most recent year figures were available. A number of companies also have stopped using corn syrup in some or all products, including Hunt's ketchup, Snapple, Gatorade and Starbucks' baked goods.
Producers blame the decline on a campaign that argues corn syrup is behind rising obesity in the U.S. and that favors sugar over the refined product, although most nutritionists find little difference between the two. They also accuse the sugar industry of pushing a campaign that has helped sugar refining increase about 7 percent from 2003 to 2008.
As of 2008, high fructose corn syrup makers produced an average of 53.1 pounds a year for every American, compared with 65.7 pounds of sugar produced for use in the U.S., according to the U.S. Department of Agriculture. The agency doesn't track consumption.
"I think what we're seeing is a real awakening of public interest and public consciousness of the food we eat," said activist Curt Ellis, a producer of the 2004 movie "King Corn" about subsidies that helped corn become a dominant U.S. crop.
Ellis added, though, that he wished Americans would stop eating so many sweeteners, whether refined from corn or sugar.
High fructose corn syrup was first developed in the 1950s but didn't come into widespread use until the 1970s and 1980s. It's made from corn starch, which is processed into corn syrup that is high in glucose. Added enzymes turn the glucose into fructose, a sugar found in some sweet fruits and honey.
Quotas and tariffs imposed on imported sugar in the late 1970s prompted food manufacturers to begin relying more on corn syrup. Coca Cola and Pepsi both switched from sugar to high fructose corn syrup in the 1980s.
Producers don't welcome the trend away from corn syrup, but seem positioned to handle it. Companies such as Archer Daniels Midland Co., Cargill Inc. and Corn Products International sell dozens of corn- and grain-derived products, and although U.S. sales are dropping, they're selling more in some other countries, especially Mexico.
Food industry observers also note the sweetener's biggest buyers — like Coke and Pepsi — remain huge customers. That's not likely to change unless sugar prices drop so low they can't resist.
"As long as they don't switch, there'll be a huge market for it," said Ron Sterk, associate editor of the trade publications Milling & Baking News and Food Business News.
Wall Street analysts who follow the companies have noted increased shipments to Mexico, where there appears to be little concern among consumers.
"We don't see the pushback in the other areas at the moment," Corn Products CEO Ilene Gordon said during an April conference call with analysts.
The U.S. campaign against high fructose corn syrup seemed to begin with a 2004 study by a pair of researchers, one at Louisiana State University and one at the University of North Carolina, that suggested a link between the substance and obesity.
Sterk said the study came just as more people were feeling uncomfortable with processed foods.
"The timing was just right because there was a whole — and there still is — a whole move toward natural things, and it was able to piggyback on that," he said.
High fructose corn syrup producers have made clear they think the sugar industry has played a role, too.
"Who benefits from the disparagement of high fructose corn syrup?" asked Audrae Erickson, president of the Corn Refiners Association.
A spokeswoman for the sugar industry trade group, the Sugar Association, declined comment.
Nutritionally, there's very little difference between the substances, and people digest them in the same way, said Bruce Chasy, a professor of food safety and nutrition at the University of Illinois.
High fructose corn syrup, he said, is slightly sweeter than sugar.
"Other than that, there's no real difference," he said. "Your body's going to metabolize it the same way."
Still, customer concerns are driving some companies to make changes.
"We heard loud and clear from our customers that they want food, when they purchase food at Starbucks, to be made of high quality ingredients and from simple recipes," said Starbucks spokeswoman Sanja Gould.
In June 2009, the company stopped using high fructose corn syrup in baked products. Gould wouldn't discuss how the move affected sales, but she said feedback was overwhelmingly positive.
The Corn Refiners Association launched its own national advertising blitz in 2008 aimed at rehabilitating high fructose corn syrup's image. It included television commercials featuring a mother pouring a child a flavored drink and a younger woman offering her boyfriend a Popsicle, then talking about how the sweetener is made from corn, has no artificial ingredients and is fine in moderation.
"There was no balanced dialogue," Erickson said of the reasoning for the campaign. "It was all erroneous."