It seems on a weekly basis we're told that something we thought was good for us is actually speeding us towards an early death.
Earlier this year, fans of a good long hard run were told they may actually be doing themselves more harm than good and should instead opt for shorter, less strenuous jogs.
In fact the study - which was widely reported all over the world - suggested it could be as bad as doing no exercise at all.
But now it would appear the authors of the Copenhagen City Heart Study have conceded they did not have enough data to make any firm conclusions.
Of the 1,000 healthy joggers who took part only 36 qualified for the 'strenuous' category, those running more then 7mph for more than four hours a week.
Of these two died over the 12-year period of the study but the researchers don't know how - it may have been linked to running or it could have been something completely unrelated.
Lead author and clinical cardiologist, Dr Peter Schnohr, told the BBC: "We should have said we suspect that it is so, but we can't say for sure.
"Everybody makes some mistakes in papers."
The media have also been blamed for "misinterpreting" and "exaggerating" the findings by the editor of the Journal of the American College of Cardiology who published the study.Suggest a correction