Oprah Winfrey has sued three Utah companies over unauthorized use of the TV talk-show hostess' name and image to promote nutritional supplements, and the Illinois attorney general also is suing one of them alleging fraudulent business practices.

The lawsuits involving about 50 entities are a frontal assault by Winfrey on those that have been using her name and that of Mehmet Oz, a doctor who appears frequently on her show, without permission to promote products for colon cleansing and combat aging.

"We know that thousands of people have been misled by these marketing practices," said Marc Rachman, the attorney for Oz and Winfrey and companies that manage their images and trademarks, on Friday. "Oprah.com has received e-mail in the thousands from people who believe Oprah and Dr. Oz are affiliated with these products and have endorsed them when they haven't."

Named in the Winfrey lawsuit are Monavie, the high flying South Jordan company selling a drink based on the açai berry of Brazil; Crush LLC of Sandy; and 456 Vital Health Systems LLC of Spanish Fork.

The attorney general of Illinois also has sued Crush and its parent company, TMP Nevada, alleging violations of that state's consumer fraud and deceptive business practices act.

The Winfrey suit alleges that after Oz, who practices at the Columbia University Medical Center, appeared several times on the show discussing health issues, the defendant companies began to market

products falsely using their names as endorsements.

A top official at Monavie said Friday it was mistakenly put on the list of "Internet scammers" who trade on the reputation of the açai as a health-promoting berry the company makes into a drink product. CFO Devin Thorpe said the company did not promote free trials of products, had a liberal money-back policy and did not say or imply that Winfrey or Oz had endorsed the Monavie açai-based juice.

"We really feel like we're the victims of these Internet scammers every bit as much as Oprah is a victim of them," said Thorpe. "Monavie really created the açai business in the United States ... And it's really [Internet scammers] trading on our good name."

Jason Brailow, a principal officer at Crush and its parent, TMP Nevada, also denied his companies used Winfrey's or Oz's names as an endorsement on the Web sites.

"They thought they were doing something we didn't do," he said.

Brailow also claimed there already was an agreement to drop the lawsuit. But Rachman, the lead lawyer, said he had not had any discussions with Brailow or his company about the lawsuit.

"I haven't discussed anything with Crush LLC," he said. "If I haven't, I don't think anyone else has."

The company 456 Health Systems -- or its related entities FCM Performance Health USA and AEG Partners Ltd. -- could not be reached for comment.

Brailow also denied the allegations in the Illinois lawsuit that the company was using deceptive Web pages to lure customers with a "risk-free trial offer" for a sample of the product, then quickly starting to charge customers' credit cards monthly for shipments. Some customers received the samples after the 14-day trial period had ended and were already being charged monthly, while others couldn't reach customer service to cancel their automatic payments, the lawsuit says.

Brailow said almost all customers who wanted their money back have had it returned and that customers can easily reach customer service representatives.

A call to one of the company's toll-free customer numbers was promptly answered Friday afternoon.

tharvey@sltrib.com