The development of our interventions is driven by findings from our observational and mechanistic work. First, we aim to improve the nutrient profile of the diet: the NIPPeR trial tests the efficacy of a nutrient supplement from before pregnancy in improving glucose tolerance in pregnancy and improving the body composition of the child. We continue collaborating with Programmes 1 and 2 in the MAVIDOS trial of vitamin D supplementation in pregnancy; our foci are the children’s body composition and respiratory health. Second, we target health behaviours before and during pregnancy: SPRING builds on MAVIDOS, but also aims to improve health behaviours in pregnancy. Another approach (MUMs) aims to modify both individual and environmental influences on dietary quality. Third, our LifeLab intervention targets teenagers, at an age when health behaviours are being established, and before they embark on having children.