The “Dr. Oz effect” usually refers to the popular talk show host’s ability to turn unproven “miracle cures” and weight loss fads into instant successes, but fortunes can swing the other way when the Great and Doctorful Oz says not-nice things about a product.

The North American Olive Oil Association filed a lawsuit on Tuesday in Fulton County Superior Court in Atlanta against Dr. Mehmet Oz, claiming that the TV personality made disparaging statements about the quality and purity of its members’ products on his talk show, Courthouse News reports.

The trade group claims that Oz and his guests on The Dr. Oz Show “made a series of false statements regarding the quality and purity of olive oil sold in supermarkets in the United States, including but not limited to imported olive oils.”

“The statements made on The Dr. Oz Show caused harm to plaintiff’s business, including the Quality Seal Program, and to plaintiff’s reputation and ability to continue its work,” the complaint reads.

This all started with the May 12, 2016 episode of the show, when Oz and his guests discussed the “truths” about certain foods, olive oil included. On that program, Oz spoke to a guest introduced as a “certified oleologist.”

That guest “is employed by the California Olive Ranch, a privately owned company based in Chico, California that manufactures and sells olive oil made in California,” the complaint says. “At no point in the show did any person disclose [the guest’s] vested interest in denigrating olive oils originating outside of California or her vested interested in promoting California olive oils.”

According to the suit, Oz claimed during the episode that a “shocking” 80% of olive oil products could be a scam, and that it probably contains less actual olive oil “than you’ve ever imagined.”

“It’s likely been mixed with artificial colors and less expensive oils. In other words, you are not getting what you’re paying for,” he said during that episode.

The group says Oz tried to back up his claims by mentioning Italian police who discovered “7,000 tons of fraudulent olive oil, much of it bound for storage right here in America.”

“By making that statement, Dr. Oz unequivocally implied that the olive oil seized by Italian authorities was, among other things, tainted by oils from non-olive sources,” the complaint says. “But the truth is that none of the olive oil seized by Italian authorities was alleged to have come from non-olive sources. Similarly, there were no claims that the olive oil contained artificial colors or was in any other way ‘adulterated.’”

Oz’s statements weren’t based on “reasonable or reliable scientific inquiry, facts or data,” the group claims.

That kind of talk is harmful on its face, but it’s made worse by the fact that his viewers take whatever he suggests seriously, and use that information to make decisions when shopping for food, the suit says.

So why would Oz talk alleged smack about foreign olive oil? Because he wants to promote California olive oils instead, the trade group claims, and keep viewers from buying olive oil produced elsewhere in the country.

The lawsuit seeks consequential and punitive damages for claims of disparagement of perishable food products, tortuous interference with business relations and negligent misrepresentation.

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