All those confusing nutrition messages? Yeah, they aren’t so good. From Rebekah Nagler’s 2010 UPenn dissertation abstract:
Measures of media exposure to contradictory messages were developed and validated for the purposes of this research, and results show that exposure is associated with negative outcomes. Specifically, exposure to conflicting information on the health benefits and risks of, for example, wine, fish, and coffee consumption is associated with confusion about what foods are best to eat and the belief that nutrition scientists keep changing their minds. There is evidence that these beliefs, in turn, may lead people to doubt nutrition and health recommendations more generally—including those that are not rife with contradictory information (e.g., fruit and vegetable consumption, exercise behavior).
Akin to analysis paralysis perhaps?