A Systematic Literature Review of Impactful Food Waste Interventions
Quelle: Diana Oborska, unsplash.com
Agroscope researchers conducted a literature review to summarise which measures are most effective in reducing food waste. Their findings contribute to better identification and implementation of effective interventions.
Generating over one billion tonnes of food waste per annum globally, consumers make a substantial contribution to the total volume of wasted food. It follows that interventions focusing on altering consumer behaviour are an important leverage for reducing or avoiding food waste. However, to effectively reduce food waste, in-depth knowledge on the effects of such interventions is essential.
Agroscope researchers therefore conducted a systematic literature review, analysing a total of 49 studies that investigated 54 interventions for reducing consumer-level food waste. Both consumption in the household and outside of the home (e.g. in restaurants, university canteens, etc.) was taken into account. The studies considered were evaluated according to three criteria (see Figure 1).
Intervention category
The majority of the 54 intervention studies investigated single-component interventions, such as nudges, knowledge enhancement, awareness raising, social influence or incentives. A ‘nudge’ involves the use of subtle tools to influence and modify consumer behaviour and decision-making: for example, using a smaller plate may lead to smaller portions being taken, and hence to less food left unconsumed on the plate. Only a few studies tested multi-component interventions. In these studies, nudges were frequently combined with other interventions. Most of the intervention studies were conducted in households (35%), followed by universities (24%), schools (18%), hotels (9%), supermarkets (6%), hospitals/care homes (4%), restaurants (2%) and campsites (2%). The target population varied according to the intervention settings, with household members, students, children and young people being the most frequent study participants.
Impact of the interventions
Most interventions led to a significant reduction of food waste (see Figure 2). For the following interventions – social influence, awareness raising, knowledge enhancement and nudges – there were several studies leading to no reduction in food waste. Multi-component interventions with nudges proved to be particularly promising for reducing food waste. The most effective reduction was achieved by a combination of nudges with knowledge enhancement. The use of individualised training sessions and customised solutions with a coach, including nudges such as tips by text, email or phone led to a significant reduction of food waste of up to 79%.
Based on the study results the Agroscope researchers also suggest measures for rendering food waste intervention studies even more efficient in future, inter alia larger study populations or studies in which people do not know that food waste is being investigated. More details can be found in the scientific article.
Conclusions
- Although only small numbers of multi-component interventions were tested, these were more effective than single interventions.
- More multi-component interventions combined with nudges (where behaviour and decision-making are influenced and modified by subtle tools), as well as randomised controlled studies are necessary.
- A harmonisation of the methods (e.g. how food waste is measured, the study design) is necessary to enable better comparison of food waste data.
Bibliographical reference
A systematic literature review on impactful food waste interventions at consumer level.
