Deciding between healthy ageing and early dementia; how useful are modern imaging techniques in deciphering this difficult question that many families are grappling with. Margaret McCartney tries to make sense of conflicting research on the impact of fish oils on children's reading ability and memory - how can the same research group, in the same university run two trials and get completely opposite results? And recently Baroness Tessa Jowell called for more access to adaptive trials but what does this type of research actually mean for patients taking part? Plus the evidence for the health benefits of yoga.