When U see negative remarks re altmed treatments from proclaimed medical people, U accept their career claims?

That is, if someone who attacks alternative medicine states they are a doctor, nurse, etc, will you swallow that statement hook, line and sinker, or will you be sceptical ( pun intended ) ? Ditto with somebody who claims they have been miraculously cured of an illness through an as yet unproven conventional treatment, will you believe it ? Why or why not ?