Did the "hardest working man in show business" literally "do it to death"?

That's one theory being floated by some of James Brown's friends and doctors, who say Brown's Christmas death at the age of 73 is linked to overwork. Via UPI:

Brown also had recent dental surgery. The dentist who treated him told the Atlanta Journal-Constitution that he had advised Brown to slow his schedule down to heal from the surgery, but Brown insisted on appearing at several upcoming shows.

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