Background: Increased global demand for imported breast milk substitutes (infant formula, follow-on formula and toddler milks) in Asia, particularly China, and food safety recalls have led to shortages of these products in high income countries. At the same time, commodification and trade of expressed breast milk have fuelled debate about its regulation, cost and distribution. In many economies suboptimal rates of breastfeeding continue to be perpetuated, at least partially, because of a failure to recognise the time, labour and opportunity costs of breast milk production. To date, these issues have not figured prominently in discussions of food security. Policy responses have been piecemeal and reveal conflicts between promotion and protection of breastfeeding and a deregulated trade environment that facilitates the marketing and consumption of breast milk substitutes. Discussion: The elements of food security are the availability, accessibility, utilization and stability of supply of nutritionally appropriate and acceptable quantities of food. These concepts have been applied to food sources for infants and young children: breastfeeding, shared breast milk and breast milk substitutes, in accordance with World Health Organization (WHO)/United Nations Children's Fund (UNICEF) guidelines on infant feeding. A preliminary analysis indicates that a food security framework may be used to respond appropriately to the human rights, ethical, economic and environmental sustainability issues that affect the supply and affordability of different infant foods. Summary: Food security for infants and young children is not possible without high rates of breastfeeding. Existing international and national instruments to protect, promote and support breastfeeding have not been implemented on a wide scale globally. These instruments need review to take into account the emerging trade environment that includes use of the internet, breast milk markets and globalised supply chains for breast milk substitutes. New approaches are required to handle the long-standing policy conflicts that surround infant and young child feeding. Placing breastfeeding in a food security framework may achieve the political attention and policy co-ordination required to accelerate breastfeeding rates in a range of economies.