Oprah Winfrey was the first person to dub Oz — then a frequent guest on her program — "America's doctor." Today, the Emmy Award-winning "Dr. Oz Show" is one of the top-rated daily TV programs in the country, and Oz has authored a series of books, all of it turning him into a medical-media franchise.
But some other doctors are not buying the latest pitch from Oz.
"He's well aware that these companies are promoting things without any evidence of (benefits), but he doesn't do anything to preempt it," said Dr. Eric J. Topol, director of the Scripps Translational Science Institute in La Jolla, California.
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"He can claim it's all done unwittingly, or unknowingly, and that these things are being taken out of context. But his own shows demonstrate that is not that case," Topol added. "This has been perpetuated for a long time. These things he calls 'miracles,' for example. What do you think is going to happen when you call something a miracle and there is absolutely no evidence?"
The real magic, Topol said, is the size of Oz's viewing audience. For years, scientifically unproven products were peddled on late-night infomercials, seen by a few bleary-eyed insomniacs. But Oz, he said, has "taken it to an uber level of dissemination that wasn't possible before."
"He does sometimes seem like a televangelist," added Dr. David Gorski, assistant professor of surgery at Wayne State University.
"A lot of it just has to do with his gushing over a product. People seem to believe Dr. Oz. I don't know why, but they do," Gorski said. "Any product that there's a hunger for –- if you have millions of viewers every day, and if you've built up this brand, quote-unquote America's doctor -– you're going to get people wanting to buy whatever it is you say is great."