Although an infant’s development during complementary feeding (6–24 months of age) is genetically pre-programmed, environmental exposure and optimal nutritional supply are still important. Numerous studies have associated specific aspects of nutrition during this period with developmental outcomes. In this presentation, Dr Gould presented an overview of research involving interventions with macro- and micronutrients and its role on developmental outcome. Observational studies have associated nutrient deficiencies with impairments in intellectual abilities, work capacity, behavioural functioning and even delayed mental and motor development. However, there are inconclusive results from randomized controlled interventional trials using food, individual nutrients, or multiple micronutrients. This may have been due to poor adherence, particularly seen in studies in which families were assigned to the intervention arm, and the use of incorrect measures or assessments at unsuitable ages. Results of intervention with multiple micronutrients appear promising but most of those studies did not assess child development outcomes.