The year 2016 witnessed the anniversaries of several key events related to the prevention of neural tube defects (NTD) with folate supplementation. However, the road leading up to this achievement was full of stumbling blocks, both in terms of research ethics and researcher ethics. First, the decisions of ethics review boards differed with respect to allowing placebo groups in folate trials, thus reducing the level of evidence obtained from the earliest studies. Second, statisticians insisted on analysing the outcome of a trial by intention-to-treat – which turned out to be non-significant – rather than by treatment received, which was statistically significant. Third, the recognition of positive results was stymied by the reluctance of some researchers to recognise and quote others' contributions. All this needlessly delayed the recognition of the NTD-preventive effects of folate by a decade. The story of the prevention of NTD thus offers insights into research inadequacies that have the potential to impede the advance of medical science, with the ethical aspects having the most immediate impact. Efficient ethics review boards play a major role worldwide and if they play safe, they may risk disallowing high-quality studies of great public health import.