"It's not true. It's not true," Kirstie said.
"So there's no connection between your diet program and [Scientology?]" Meredith asked.
"God no! No. Zero," Kirstie answered.
Hollywood blogger Roger Friedman appeared in a pre-taped package on "Today" and claimed there was, in fact, a connection.
"The company's headquarters is in Clearwater, Florida in the same building as one of the Scientology offices," Friedman said.
"The address in Clearwater is my accountant, and he's a Scientology Jew," Kirstie said.
Meredith pressed the issue, saying, "Well, I think there are a lot of people, truth be told, who think anything connected to Scientology is quackery… and they look at the diet and they start to draw lines. And they wonder, 'Do any of the profits from this company go to Scientology?'"
"No. I'm way too cheap to do that," Kirstie said with a laugh.
Access Hollywood has learned that Kirstie cancelled a follow up appearance on the fourth hour of the "Today" show with Hoda and Kathie Lee set for Thursday.
Following her "Today" appearance, Kirstie Tweeted, "Good morning!!!! Just experienced the meaning of BLINDSIDED…..delivered with a smile…. Shame on you Today Show…Shame on you."
Followed by another Tweet warning blogger Roger Friedman about his claims.
"GOING TO HAVE Mr. Attorney call Mr. Friedman's Attorney tomorrow..Mr. Friedman is treading on thin LIBELOUS ice with my company. Crackkkk," she wrote.
And despite the "Today" incident, Kirstie still has love for co-host Meredith.
"P.S. I do NOT hate Meredith…just STRIKE one on blindsiding..and my bad..didn't see the "do you STILL beat your wife" ambush coming…WHAP" Kirstie wrote in a later Tweet on Tuesday.
Kirstie, who is promoting her new reality series "Kirstie Alley's Big Life," continued her media blitz with appearances on "Live With Regis and Kelly" and "The Late Show," where she received an apology from David Letterman.
"In the last couple of years, I've made many, many jokes about you being overweight or having a weight problem," Letterman said. "So, I'm embarrassed now, and if I need to apologize, I'd like to apologize."
"No, because we make fun of you at my house," Kirstie told Dave.
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