Diet soft drink
A preliminary abstract presented by the University of Miami's Hannah Gardener linked daily consumption of diet soda to a 61% higher incidence of "vascular events" such as strokes and heart attacks, although Gardener acknowledged that these results could not be conclusively linked to harmful effects of diet soda itself, and may be the result of other behaviors. The author stated confirmation was required prior to drawing conclusions.  These studies were published as abstracts and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal