Getty Images/Roger Kisby He's the nation's most powerful celebrity doctor, a Columbia University heart surgeon, and, by many recent measures, a bit of a nut.

Over his 11 years on TV — starting as a guest on Oprah and then as the star of his own self-named show, Dr. Mehmet Oz has publicly endorsed dozens of egregiously un-scientific "quack" treatments.

Last week, ten top physicians called for Dr. Oz to be removed from Columbia's faculty list because he has "repeatedly shown disdain for science and for evidence-based medicine."

Here are five of of his most eccentric recommendations:

Plant-based "magic" weight loss cures

Dr. Oz has backed several plant-based "cures" which he's said can help people lose weight, from coffee bean extract to the extract of a Southeast Asian fruit named Garcinia cambogia.

"You may think magic is make-believe, but this little bean has scientists saying they've found the magic weight-loss cure for every body type," Oz said of green coffee extract on one of his show's episodes in 2012.

Unfortunately, there was only one study backing the green coffee's alleged weight-loss capabilities, and it was funded by the extract's manufacturer. Plus, a few months after it was published, it was retracted when its authors said in a statement that they "cannot assure the validity of the data."

Communicating with the dead to reduce stress

Oz has brought several self-proclaimed "spiritual mediums" on the show, where they've done everything from psychic readings to telling audience members how their loved ones actually passed (one of Oz' guests told an audience member that his son, who had died in a car accident, had actually committed suicide, the Los Angeles Times reports), and giving advice.

Connecting with the dead, Oz has said, can help lower stress levels by helping people make peace with their deceased loved ones.

More recently, he's even shown the audience before-and-after brain scans to show them that psychics attain a "different type of consciousness" when they "connect with the other side." Never mind that these scans could literally show anything. They're done with an EEG, which simply shows relative activity in different areas of the brain, and taken once before and again during the readings. That means the "results" (meaning the difference in before and after scans) could simply show something like elevated anxiety. The images are so unclear, however, it's hard to even determine this type of result.

Super-diluted remedies for everything from colds to the flu

Oz has publicly endorsed homeopathy, super-diluted doses of medications that have been repeatedly shown to be ineffective. In 2011, he invited self-proclaimed "alternative medicine" practitioner Russ Greenfield on his show to explain to the audience what these treatments were.

Homeopathy, his guest says, is a treatment that contains "the essence of the medication — oh, let’s say the spirit of the medication." He then went on to say that that spirit "sends a message to the body to heal itself."

The "spirit" of the medication, unfortunately, has been shown to be entirely insufficient to treat any known condition. In 2005, medical journal The Lancet published a large study comparing homeopathic remedies and conventional medical treatments with placebos. They concluded that any effects of homeopathy were largely the same as those of placebos.

"Miracle appetite suppressants"

While Oz touts coffee bean extract as the key to burning fat, he says the Middle Eastern cooking staple saffron will curb your cravings. On a January 2014 episode of his show, Oz went so far as to call saffron a "miracle appetite suppressant."

As of yet, not a single independent study of the ingredient have found that it helps with weight loss or appetite suppression.

"Harnessing energy" to help patients survive risky surgeries

In his 1998 book Healing from the Heart, Oz describes some of his more "experimental" work with registered nurse Jery Whitworth. The pair founded the Cardiac Complementary Care Center at Columbia-Presbyterian in 1994 with the idea of experimenting with different types of alternative medicine and keeping the approaches that worked.

During these experiments, Oz tried bringing Reiki, or "energy healing," into the operating room to encourage "the body’s own energy to help patients survive risky operations, such as heart transplants," the New Yorker reports.

Scientific studies of Reiki have shown it has had little to no effect. A 2011 study looking at pain in women who recently had C-sections found that Reiki did nothing to reduce symptoms.



Yet that did nothing to stop Oz from telling his audience in a more recent episode that his wife, Lisa Oz, is a Reiki practitioner and frequently uses the practice to help heal their children.