Objective To use the north Queensland banana industry as a case study to examine the extent to which cosmetic standards set by retailers influence the amount of edible waste generated on-farm and the effect of this on the sustainability of the Australian food and nutrition system.Design Waste audits were performed on-farm at a banana packing shed to quantify the amount of fruit discarded due to cosmetic imperfections. These data, together with production records provided by the Department of Primary Industries and Fisheries and interviews with growers, were used to inform a nutritional analysis, a life cycle assessment and an economic analysis to quantify nutritional, environmental and economic impacts.Setting North Queensland, AustraliaSubjects Banana farms and packing shed.Result Between 10 and 30 % of the north Queensland banana crop is discarded on-farm. Of this, 78 % was found to be due to cosmetic imperfections, which equates to an industry total of 37 000 tonnes per annum. This waste represents a loss of 137 billion kilojoules with accompanying macro- and micronutrients. The life cycle assessment indicated that approximately 16 300 tonnes of carbon dioxide emissions, 11·2 gigalitres of virtual water as well as other natural resources are embodied in the waste. There is an industry-wide, economic loss of approximately $AU 26·9 million per annum.Conclusions The majority of on-farm banana waste is caused by arbitrary cosmetic standards set by retailers, resulting in significant nutritional, environmental and economic losses. Public health nutritionists have a role to play across the entire food chain to minimize the impacts of waste on the food system.