UPDATE 2-US FDA warns over Diet Coke Plus nutrition claims

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WASHINGTON, Dec 23 (Reuters) - Coca-Cola Co's KO.N claims that Diet Coke Plus includes a variety of vitamins and minerals violate U.S. policy against marketing soda and other snack foods as more nutritious, or "fortified," health regulators said in a warning letter to the company.

“The FDA does not consider it appropriate to fortify snack foods such as carbonated beverages,” the U.S. Food and Drug Administration agency told the beverage giant in a letter dated Dec. 10 and made public on Tuesday.

It was not clear if the FDA was seeking to remove the product from the U.S. market, and a spokesman for the FDA had no immediately comment.

“You should take prompt action to correct the violations,” the FDA wrote. The agency could take further action, including seizing products, seeking injunctions and levying fines.

Manufacturers routinely try to boost the value of their foods and beverages by adding extra nutrients.

The FDA allows such claims when foods or beverages contain at least 10 percent of the recommended daily allowance of a vitamin or mineral. But the claims cannot apply to soda or certain foods, including candy, its regulations state.

Representatives for Coca-Cola defended the calorie-free product’s claims.

“This does not involve any health or safety issues, and we believe the label on Diet Coke Plus complies with FDA’s policies and regulations,” company spokesman Scott Williamson told Reuters.

Coca-Cola has marketed Diet Coke Plus as “a good source of vitamins B3, B6, and B12, and the minerals zinc and magnesium.” It was launched in the United States in April 2007.

It is part of its Diet Coke line of products, the calorie-free alternative to regular Coca-Cola beverages.

The executive director of the Center for Science in the Public Interest, Michael Jacobson, said Coca-Cola blatantly ignores FDA rules in its marketing of the product.

He also said a fortified product allows a company to charge more, even though consumers don’t need the extra nutrients -- especially from a less healthful drink such as soda.

“Fortification is dirt cheap and allows companies to charge more,” he told Reuters. “People would be better off drinking water than Diet Coke Plus.”

Diet Coke and Diet Coke Plus are “comparably priced,” Coca-Cola’s Williamson said.

The company has 15 days to outline plans to correct the issue, and Williamson said Coca-Cola would reply to the FDA letter in early January.

The FDA released the warning letter on its websitehere (Reporting by Susan Heavey; additional reporting by Aarthi Sivaraman in New York; editing by Jeffrey Benkoe, Gary Hill)