Our perennial pseudo-confusion about diet — and pseudo-confusion, it is — is fueled by two parallel delusions, running in opposite directions. The first is that every opinion about diet changes the facts about diet; it does not. This delusion operates as if bias, preconceived notion, having the answer before asking the question, or having something to sell — is fully commensurate with expertise and the weight of evidence.
The second, opposing delusion is that every opinion about the evidence about diet changes the standard of “sufficient evidence.” It does not. This contention harbors the view that any amount of evidence can be dismissed as inadequate or even absent by those who find the message in it inconvenient.