Information on diet in ALSPAC has been collected regularly in parents and children, starting with the the mother's diet in pregnancy using a postal questionnaire. This information has been used many times to look at how the mother's diet affects the health and development of her child, as well as her own health. This information has been made available to many researchers, but we'd like to write a summary for researchers detailing exactly what is available, how we have processed the information in various ways to make it useful for different types of research studies, and how to access it.