(AP) -- The setting sun splashes warm hues across a ripening cornfield as a man and his daughter wander through rows of towering plants.
Like any parent, the dad says in the television commercial, he was concerned about high fructose corn syrup. But medical and nutrition experts reassured him that in essence, it's the same as cane sugar.
"Your body can't tell the difference," he says. "Sugar is sugar."
That key claim, made last year by the corn industry as it tries to rebrand high fructose corn syrup as simply "corn sugar," was weighed for the first time by a federal judge Tuesday after a group of sugar farmers and refiners sued corn processors and a lobbying group.
Their lawsuit alleges the father-in-the-cornfield advertisement and other national television, print and online commercials from the corn industry amount to false advertising because sugar is not the same as high fructose corn syrup, the sweetening agent now found in the bulk of sodas and many processed foods.
Sugar makers say there are numerous differences between the white, granular product and the sticky liquid that is high fructose corn syrup. Attorney Adam Fox claimed the syrup industry has even acknowledged as much in the past.
At a hearing on the corn industry's motion to dismiss the lawsuit, Fox showed U.S. District Judge Consuelo Marshall the papers from a case in Mexico filed by the Corn Refiners Association that carefully outlined how sugar and high fructose corn syrup are different. That case in 1997 was related to the export of high fructose corn syrup to Mexico.
"Like the horse and the automobile, sugar and (high fructose corn syrup) are two different products in terms of their physical and functional characteristics, as well as in their production process, distribution and commercial application," corn industry expert Peter Buzzanell stated in an affidavit at the time.
Corn industry lawyers counter that Fox was taking such statements out of context because the Mexico case dealt merely with the physical properties of high fructose corn syrup and never addressed the manner in which the body processes it.
"Sugar and high fructose corn syrup are equivalent as far as how they are metabolized by the body," attorney Dan Webb said.
Webb and other lawyers had filed a motion to dismiss the sugar makers' lawsuit on the grounds that the advertising campaign is protected speech because it forms part of a national conversation about the merits and pitfalls of high fructose corn syrup and sugar in general.
"At the core of this case is clearly a lawsuit filed by the other side that is attempting to stifle debate," Webb said.
He also argued that because the Corn Refiners Association is an industry group and does not directly sell any products, it cannot be sued for false advertising.
Without providing a timeline, the judge said she would issue a ruling on the dismissal motion.
High fructose corn syrup's image has suffered in recent years after public awareness of its widespread use increased and some studies suggested a link to rising obesity levels. Americans increasingly blame the syrup for a range of health problems, and first lady Michelle Obama has said she does not want her daughters eating it.
The American Medical Association has said there's not enough evidence to restrict the use of high fructose corn syrup, although it wants more research.
A year ago, the Corn Refiners Association asked the Food and Drug Administration if it could start using the term "corn sugar" as an alternative to high fructose corn syrup. It could take another year for the FDA to decide on the name, but the corn industry didn't wait before it started using it in advertisements.
Sugar industry lawyers claim corn refiners have already spent $50 million trying to persuade the public to accept corn sugar as a name.
It would not be the first time a food has been rebranded. In 1988, for instance, low erucic acid rapeseed oil became much more popular after it was renamed "canola oil."
More than 100 citizens and consumer groups have written to the FDA as it weighs the name change, many of them slamming the rebranding as a cynical attempt to confuse customers who may be wary of high fructose corn syrup.
"Given the current controversy, consumers who look to avoid (corn syrup) should be able to easily differentiate among products that do and don't use (it)," the Consumers Union, which publishes Consumer Reports, wrote to the FDA.
Expert opinion was divided on high fructose corn syrup. Michael Jacobson, executive director of the Center for Science in the Public Interest, has said that there was no evidence that the sweetener is any worse for the body than sugar.
Michael Goran, a professor of preventive medicine and director of the Childhood Obesity Center at the University of Southern California, said he does not give his kids products containing high fructose corn syrup because it contains high levels of fructose, which can be stored in the liver as fat and trigger gout and hypertension problems.
"As a father and as a consumer, I like to know what I am eating," he said. "The industry has done a very good job trying convince people it's sugar from corn. It's not ... it's manufactured from corn by a highly industrialized process."
Goran and other professionals say the healthiest option is consume smaller amounts of all sugar.
"The U.S is the highest consumer of sugar in the world," Goran said. "To prevent obesity and diabetes, we should be consuming less sugar in general."
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