I am always leery of people who introduce themselves as "Dr. So-and-so." A medical doctor says, "I am Joe Blow, M.D."

According to Wikipedia, Michael Mosley of this series went to medical school planning to become a psychiatrist, grew disenchanted with psychiatry, and joined the BBC at age 28.

His advice may be fine, but although he says "I'm Dr. Michael Mosely," he is not a medical doctor.
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In choir I learned that a good way to take a deep breath is to pretend that you are breathing in through a straw.