Oz has made his preference known for privatized Medicare, which could substantially disrupt the current system.

Dr. Mehmet Oz, Donald Trump's pick to oversee Medicare and Medicaid, has evolved on health care policy over the years.

Mehmet Oz, a celebrity heart surgeon turned talk show host and lifestyle guru, is President-elect Donald Trump’s pick to run the Centers for Medicare and Medicaid Services, the massive federal health care bureaucracy that covers more than a third of Americans.