David Berg, the CEO of Moorhead-based American Crystal Sugar Co., swears he has nothing “useful or relevant” to offer to a long-running lawsuit that pits the refined sugar industry against the high-fructose corn syrup industry.

Minnetonka-based agri-giant Cargill Inc. and other corn syrup producers want to depose Berg after being sued by sugar groups over marketing claims. The syrup producers say Berg helped hatch plans to “vilify” the corn syrup industry as a director of the Sugar Association, even though American Crystal, the nation’s largest beet sugar producer, dropped out of the trade group to avoid litigation filed in 2011.

The maneuvering is part of a multimillion-dollar legal battle for the nation’s multibillion-dollar sweetener market. At issue is whether corn syrup is nutritionally the same as sugar, as the syrup makers assert, or a less natural product that is inherently less healthy.

The feud has led two of Minnesota’s agricultural titans to increasingly take aim at each other in what some observers see as a fight for sales, not consumers’ well-being. Walter Willett, who chairs the nutrition department at Harvard’s School of Public Health, calls the sweetener war “a struggle over market share” in a “game among industry giants.”

In a new legal filing last week, corn syrup lawyers offered internal communications Berg wrote that called for the sugar industry “to delay or stop” the U.S. Food and Drug Administration from designating high fructose corn syrup as “corn sugar.” In those memos, Berg said that sugar groups should obstruct the syrup industry “with blunt force, or degrees of finesse, but we have to oppose them.”

American Crystal, which had $1.6 billion in 2013 revenue, did not respond to a request for information on Berg’s involvement in any campaign to discredit corn syrup.

Cargill, a private company that derived an unknown share of its $2.3 billion 2013 profits from milling corn into syrup, deferred comment on Berg’s subpoena to a co-defendant, the Corn Refiners Association.

“We have endeavored to gather information relating to these matters from other representatives of the Sugar Association, but they have disclaimed knowledge and claimed not to be able to recall relevant facts and events,” Corn Refiners President John Bode said in an e-mail to the Star Tribune.

Adam Fox, a lawyer for sugar groups involved in the suit, predicted that Berg will not be deposed because the deadline for submitting facts discovered in the case was June 30. Fox also accused Cargill and other large agribusinesses, including Archer Daniels Midland, of trying to hoodwink consumers by forming a group called “Sweet Surprise.”

Fox says the group undertook a “$100 million advertising campaign to convince the American people that high-fructose corn syrup is natural” and “no different than sugar.” Fox called the claims false and misleading.

The Sweet Surprise website includes blog entries with titles such as “Fructose and Causes of Obesity: The data shows poor link.” It features articles like “The Media and Food Fears,” which begins, “In recent years, [high-fructose corn syrup] has been singled out in the media as the main cause of obesity and other health problems even though there is no conclusive scientific evidence to support such allegations.”

Meanwhile, corn syrup defenders say communications obtained in the lawsuit expose the sugar industry’s financing of research and planting of news stories aimed solely at the “vilification” of corn syrup. One 2004 memo from Sugar Association President Andrew Briscoe explains that the trade group has “fed the media with the science to help fuel the public concern and debate on [high-fructose corn syrup].”

By 2008, Briscoe explains that efforts to bring troubling scientific information to the academic community and the media “has helped to connect the dots and help clarify [high-fructose corn syrup] and all free-fructose corn-based sweeteners as a concern.” Briscoe cites decreases in corn syrup deliveries and increases in raw sugar deliveries as proof.

Heavy consumption

With some research showing Americans consuming 15 times as many sweeteners as they did in the 18th century, public health specialists call the lawsuit an exercise in picking your poison.

“The truth is we’re having a problem consuming pharmacologic doses of sugar in any form over the past decade,” said Dr. Mark Hyman, a physician specializing in ways lifestyles and environment affect health.

Doctors say the distinctions being debated are unlikely to benefit consumers. Mary Schmidl, a professor in the University of Minnesota’s department of food science and nutrition, said the suit is “about two organizations that both make similar products and want to provide ‘sugars’ to the general public.”

There are differences in the chemical content of refined sugar and high-fructose corn syrup. Sweeteners are made up of fructose and glucose. In sugar, the two elements are chemically bonded in a 50-50 ratio. High-fructose corn syrup has no chemical bond between fructose and glucose and contains more free fructose than free glucose — anywhere from 55 to 75 percent, according to Hyman.

Fructose goes directly to the liver and gets processed into fats like the kind that can produce cholesterol and clogged arteries. Glucose gets absorbed quickly by the body and can cause spikes in insulin.

All of this can lead to weight gain, type 2 diabetes, heart disease, cancer, dementia and other ailments.

While Hyman acknowledges the differences between sugar and corn syrup are “small,” he finds the sales pitch of Cargill and other corn syrup interests to be self-serving and deceptive.

“I think they are complicit in our obesity epidemic and our chronic disease epidemic,” said Hyman. “They should be held accountable for the products they are producing that hurt people.”

Hyman says the production process for high-fructose corn syrup requires an alkali substance containing mercury that can get into foods and beverages. He says digesting high-fructose corn syrup can take so much energy that it may loosen molecular bonds in the intestinal system and cause toxins to leak into the body.

Cargill spokeswoman Nicole Reichert called Hyman’s comments “disappointing.”

“Decades of sound scientific study have shown that sweeteners, such as sucrose and high-fructose corn syrup, are nutritionally equivalent, safe and fine in moderation,” Reichert said in an e-mail to the Star Tribune.

Even Hyman, who favors warning labels on foods and beverages containing high-fructose corn syrup, believes the sugar-corn syrup legal conflict is about “politics and positioning” rather than public health.

High-fructose corn syrup is definitely different from sugar refined from beets or cane, he said. But how much those differences matter for things like weight gain and diabetes is unclear.

“On a grain-for-grain basis, is high-fructose corn syrup that much worse [than refined sugar]?” Hyman asks. “There’s some evidence that it is and some evidence that it isn’t.”

Whoever wins in court, Harvard’s Willett says America’s problems with obesity, diabetes, clogged arteries and fatty livers will almost certainly remain.

“People’s tastes have been ratcheted up to anticipate sweetness,” he said. Food and beverage manufacturers have increased the content of refined sugar or corn syrup in their products to the point where many Americans don’t appreciate “the gentle amount of sweetness in a fresh carrot or apple.”

His advice to people weighing the legal arguments about sweeteners: consume fewer of them.