In the wake of the news this week that Dr. Mehmet Oz, the star of “The Dr. Oz Show,” and a handful of others are being sued by a viewer who claims Oz’s advice left him with third-degree burns, old debates over the sometimes-dangerous lure of celebrity gurus are once again heating up.

In a lawsuit filed March 15 in the New York State Supreme Court in Manhattan, Frank Dietl, a 76-year-old New Jersey man, said he was rendered “sick, sore, lame and disabled” after trying out a home treatment the show dubbed “a heated rice footsie.” Oz promoted the treatment in a segment called “Dr. Oz’s 24-Hour Energy Boost” on or about last April 17, when he reportedly encouraged fatigued viewers to fill their socks with rice and heat them in a microwave. “Lie for about 20 minutes with those socks on in bed,” Oz told viewers. “The heat will divert blood to your feet.”

But Dietl, who is diabetic, suffers from neuropathy, which causes decreased sensation in his feet, according to the lawsuit. After leaving the socks on because he was unable to feel the heat, Dietl said he was left with horrible burns on his feet. Dietl’s lawyer told told the New York Daily News that Oz offered “no warnings to anybody with neuropathy to not try it.”

Whether Oz and his co-defendants will be deemed responsible for Dietl’s injuries remains to be seen. While doctors can certainly be held liable for patients who become injured under their care, Dietl was merely a viewer, with no doctor-patient ties to the celebrated surgeon.  “Without a relationship between the two, Dr. Oz may be able to avoid liability completely,” legal analyst Andrew Lu wrote on the Celebrity Justice blog. “Then again, because Dr. Oz promotes himself and his expertise, an argument could be made that he owes a duty of care to all his viewers.”

Regardless of how the lawsuit plays out, one thing is certain: A sizable number of Oz critics will not be rooting for America’s most famous TV doc. Although Oz was an accomplished cardiothoracic surgeon before his transition to guru status, he has since earned a growing number of detractors who say he now exploits the cult of celebrity as a means of selling questionable health advice to a gullible public.

Oz been accused of practicing pseudoscience by the James Randi Educational Foundation, relying on shoddy data by authorities cited by the New Yorker, and just being a kind of snake-oil salesman by Slate. They’re all charges that have been lobbed at celebrity gurus in the past. Dr. Phil, the Oprah-groomed tough-love relationship counselor, has few cheerleaders within the ranks of legitimate psychology. Dr. Drew Pinsky, the go-to talking head for anyone in need of an addiction specialist, has been called out on repeated occasions for passing judgment on the mental state of celebrities he’s never met.

In the case of Oz, some of the strongest criticism comes from within the medical community itself. Val Jones, a former medical student at Columbia University, where Oz has taught with the department of surgery, wrote on the Better Health blog in 2011 that a close friend put her life at risk by following Oz’s advice. The woman apparently swore off mammograms, despite a family history of breast cancer, because she’d heard from Oz that mammograms themselves cause cancer. Jones was aghast.

“How does the average layperson know how to evaluate Dr. Oz’s health claims?” she wrote. “When Oprah’s network promotes him as ‘America’s physician,’ the platform itself offers him credibility, and a reach that can damage and misinform millions like my friend.”

In a Science-Based Medicine blog post earlier that year, David Gorski, a colleague of Jones’, documented what he saw as the deteriorating state of Oz’s professional credibility, which he said hit free fall after Oz was plucked for celebrity grooming by Oprah Winfrey and eventually given his own show. One particular low point, Gorski wrote, came when Oz featured John Edward, medium extraordinaire, as a guest on his program. Oz even allowed the “Crossing Over” host to give his audience “advice on how to harness their psychic powers.”

Granted, as a world-famous surgeon with his own media enterprise, Oz is going to be a target for criticism. And he’s by no means the first celebrity guru to find himself on the receiving end of a lawsuit. (Dr. Phil, as the Daily Beast reported in 2011, has weathered his share of litigation.) But in light of last week’s lawsuit -- and amid accusations of quackery from a growing number of health-care professionals -- it’s worth asking whether the heightened position of celebrities ultimately renders them ill-equipped to dispense medical advice to millions of strangers.

In his lengthy and illuminating profile of Oz last month, New Yorker staff writer Michael Specter wondered, “Is the most trusted doctor in America doing more harm than good?”

It’s the right question. Now if only we had an answer.

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