Studies show that as time passes, patients find it hard to separate myth from truth in medical information
“‘You notice that your grandmother has been taking useless medical treatments, and you’re worried,’ he said. ‘You tell her, ‘You know, Granny, shark cartilage doesn’t help your arthritis.’ You tell her three times to make sure she understands, and she seems to.’

He continued, ‘But a few days later you talk to her again and find the warnings have had precisely the opposite effect of what you intended.’ This common problem arises, Dr. Skurnik said, because in laying down a memory trace, the human brain seems to encode the memory of the claim separately from its context – who said it, when and other particulars, including the important fact that the claim is not true.

The detailed memory of the experience of learning the information begins to fade almost immediately, and the contextual clues fade faster than the core claim.”