Intervention effect of food literacy on household food waste in the KwaDukuza municipality
Authors:   , Miti Nosipho 
Published: November 2024

Background: Approximately one-third of the food produced for human consumption is lost annually across the global food supply chain. In South Africa, it is estimated that around 10.3 million tonnes of food are wasted each year. Despite food waste occurring at various stages of food production, individual households have been identified as the primary producers of food waste at the consumption stage, driven by consumer behaviour and practice. While food waste is a global concern, South Africa's household food waste mimics that of developed countries. Although household food waste studies in South Africa have gained momentum, nearly all studies focus on household food waste consumer practices. No intervention study has been conducted to change consumer behaviour towards household food waste in South Africa. Likewise, the cost of household food waste, nutritional losses, and the environmental impact of household food waste have yet to be explored through an intervention. Interventions that target a change in human behaviour towards reducing household food waste can make a meaningful impact on food and nutrition security, and the environment. Aim: This study aimed to determine the intervention effect of food literacy on household food waste in the KwaDukuza municipality. Methods: In this randomised control trial (RCT), middle and high Living Standards Measure (LSM) households from five areas in the KwaDukuza municipality used in a formative study to determine household food waste behaviour and practices were eligible to participate in the study. All households at baseline received three colour-coded bins [used to separate food waste by food categories], binliners, food labels and freezer bags to contain cooked food waste. The first objective was to calculate household food waste through a weighed food waste audit at baseline and endline. A weighed food audit was conducted at each household (n=180). Objective two of this study included calculating the cost, associated nutrient losses and environmental impact of household food waste using the results of the food waste audit at baseline and endline. The cost of household food wasted was analysed using the mean price of foods from retail stores in the study area to determine the cost (Rand value) of household food waste at baseline and end line. The nutrient losses were calculated using the South African Medical Research Council Food Finder 3 web-based software at baseline and endline. The environmental impact was calculated using the My Emission Footprint calculator for food wasted at baseline and endline. The third objective of this study was to determine the intervention effect on household food waste. Households were randomly assigned into three intervention groups, intervention 1 (n=60), intervention 2 (n=60), and the control group (n=60). Households who were part of Intervention 1 received the food literacy toolkit and food literacy lessons on how to reduce household food waste; households in intervention 2 received the food literacy toolkits only and were reliant on self-efficacy to use the toolkit and households that were part of the control group did not receive any intervention. Results: Findings from the food waste audit showed that at baseline, the total mean of household food waste produced by all households (n=180) in this study was 1.53 kg (1531.29 g) per week, decreasing to 0.31 kg (307.47 g) per household/ week at the endline. A significant reduction of household food waste was recorded post-intervention (average waste per household = 307.47 g) When household food waste was separated into categories of the type of food wasted, the fresh produce pre-intervention (average waste per household = 917.73 g) was significantly more than the fresh produce postintervention (average waste = 173.43g). Meat produce wasted pre- (average waste per household = 109.56g) also surpassed the meat produce wasted post- (average waste per household = 43.26g). The cooked food wasted pre- (average waste per household = 387.07 g) was significantly greater than the cooked food post- (average waste per household = 76.39 g)-. The cost of food waste for the whole group pre- (average waste per household = R145.57) was significantly more than the cost of food waste for the whole group post- (average waste per household = R39.75). In terms of the environmental impact, the pre- (average waste per household = 7664.13 gCO2e) exceeded the environmental impact post- (average waste per household = 6407.67 gCO2e). A high nutrient loss from household food waste was recorded at baseline, and there was a significant reduction of macro-and micronutrient nutrient loss at the endline for the whole group (n=180). In intervention 1, intervention 2 and the control group, most nutrient losses such as energy, total protein, total lipids, total carbohydrates, and total dietary fibre were greater during the pre-intervention phase compared to the post-intervention phase. In this RCT, a significant reduction of household food waste was observed for the whole group (n=180) and across intervention groups. Following the 6-week intervention duration, between intervention arms, there was no discernible difference in household food waste, economic loss, nutritional loss and environmental impact. However, for every intervention group, there was a substantial decrease in all measured outcomes from baseline to endline. The main reason for this result could be attributed to the fact that households probably perceived that they were being monitored through the food waste audit at baseline and endline, implying that sensitisation of communities to their actual household food waste can be an impactful intervention strategy to conscientise consumers to reduce their household food waste. Conclusion: This study shows a clear linkage between household food waste, nutrition, economic and environmental impact. The disposal of food waste from households has a substantial and wide-ranging effect on the food chain, leading to various economic, environmental, and social challenges. The social ramifications of food waste are enormous, given the striking difference between the significant amounts wasted in affluent households and the prevalent hunger and food insecurity in many communities. In order to create a food system that is more environmentally friendly and able to withstand challenges, it is crucial to focus on and decrease the amount of food wasted in households. This requires a combined initiative of educating consumers, implementing effective waste management practices, and enacting legislation that encourages responsible consumption.