Summary: A recent study in India by the Defense Research and Development Organization observed a holy man who claims that he has lived for decades without food or water. A team of 30 medics are reported to have been in attendance during a 14 day observation of the man.
Can a person survive on just air? Perhaps, as a professor in the study says, "If he does not derive energy from food and water, he must be doing that from energy sources around him, sunlight being one."
There have been many claimants over the years for the Million Dollar Challenge who say that they have survived for years without ingesting any food or water. When put to the test, they fail.