Dr. Oz at times wanders off the mainstream medical path

In addition to his roles as TV host and author, Dr. Mehmet Oz is a highly respected heart surgeon and a professor of surgery at Columbia University in New York City. Much of the health advice he offers on his show — for example, his frequent reminders to get plenty of sleep and exercise — fall well within the medical mainstream. But other suggestions don’t have nearly as much scientific footing.

•Forskolin, an herbal compound that supposedly helps burn fat. A 2011 report in Obesity Review concluded that there’s meager evidence that it works.

•Coffee and vinegar. Dr. Oz has called coffee and vinegar “prevention powerhouses” that can help people avoid Type 2 diabetes. The claim is shaky at best, says Dr. Peter Lipson, an internist and clinical assistant professor of medicine at Wayne State University School of Medicine in Detroit. On the website Sciencebasedmedicine.com, Lipson calls this another example of “frankly bizarre medical opinions” from the TV doc.

•Reiki. Dr. Oz claims to be a big proponent of this form of hands-on faith healing from Japan. According to the National Center for Complimentary and Alternative Medicine, there’s no good evidence that reiki provides any health benefits or cures any illness.

•Grape seed extract. Dr. Oz says the extract can help people lose weight. A 2009 study in Diabetic Medicine found that it might help lower the risk of heart disease in people with diabetes, but any weight-loss powers remain unproven.

•Tongue examination. On a 2011 episode, guest Yogi Cameron promoted the ayurvedic theory that disorders throughout the body can be diagnosed by simply looking at the toungue. Suffice to say, this technique has not caught on in modern hospitals and doctors’ offices.

•Speaking to the dead. In a 2011 episode in which author and self-described psychic John Edward claimed to be able to communicate with the dead, Oz suggested that such psychic consultations can be a form of grief therapy. He later told Reader’s Digest that he walked out of the studio thinking, “There’s something there. It’s bizarre.” To this date, neither Edward nor anyone else has ever received a verifiable message from a deceased person.

—Chris Woolston