Choice architecture and food waste

Findings in the fields of neuroscience, behavioural economics and psychology, overturned the paradigm that conceived humans as rational calculators. In everyday life, many choices we make, or patterns of action we follow, does not stem from a rational evaluation of pros and cons. Unconscious processes have adaptively driven human behaviour and evolution, long before the initiation of conscious elaboration abilities. And it is the adaptive nature of humans that made us highly sensitive to context.
Furthermore, studies on the structure of human psychology demonstrated the presence of several psychological errors that lead people to commit mistakes in their judgements and actions. Particularly, we use mental short-cuts (heuristics) that enable us to function effectively and to respond rapidly to the environment. However, this entails that sometimes we are not making the best choice. In fact, in our everyday lives we can struggle with self-control; we have a hard time thinking in a long-term manner; we can be overly optimistic; we procrastinate, and so forth.

Cass Sunstein and Richard Thaler (Nobel Prize for Economics in 2017) are the fathers of “choice architecture” that is the design of the social environment to influence people’s decisions through the use of nudges that stimulate the optimal action or choice. As an architect designs the structure of a house, choice architects design situations that orientate people towards the most appropriate and rational behaviours.
Nudges are the tools employed by choice architects to suggest a certain path of action; they are polite, non-aggressive interventions in the social environment designed to stimulate people’s behaviour. This form of minimalist intervention aims to facilitate the adoption of a better decision-making orientating people towards healthier, sustainable, or economically rational behaviours. A number of nudges have been successfully experimented in different countries to increase energy conservation and organ donation; to reduce plastic bags usage or food waste; to fight obesity, and more (e.g. note the picture about the stairs).


Counting calories in Japan: a health-nudge to take the stairs.

As Sunstein (2013) elucidates, many obstacles lie in between humans and the adoption of pro-environmental behaviour. In relation to climate change, people assess risks using the availability heuristics, hence evaluating the probability of harm by associating it with the more ready examples that come to their mind. Our attention tends to focus on risks with an identifiable cause, and on more immediate hazards rather than on long-term ones. For these reasons, it is harder to fuel public outrage and a sense of urgency in relation to general appeals of ‘climate change’.

Nudging and food waste

One third of the global production of food is not consumed and goes to waste: this represents an unnecessary and outrageous production of greenhouse gas emissions, and use of fertilisers, pesticides, and water.  In Europe, according to a study by the European Commission, 22 million tons of food is wasted every year, with the UK being top of the list. According to FAO, annual tons of wasted food in Europe are 90 millions. Interesting discrepancies.
Nudging entail making simple, minor adjustments in the environment, which can bring huge impacts on people’s behaviour, for instance in social contexts at high risk of food waste. An option is to work on the so-called “illusion of portions”. In self-service restaurants two thirds of what is thrown away comes from the leftovers on our plate. If we think about it, a normal meal displayed on a large plate may appear tiny, leading us to fill it more. Researchers came up with the idea of downsizing the plate, to encourage people to avoid taking too much food. They tested their hypothesis in 7 hotels where guests were serving themselves from a buffet. The results were clear: people took up to 20% less on their plate. A previous study conducted by Wansink and Seabum (2000) anticipated these results. The researchers distributed awful popcorn to the subjects, but some of them ate more than others. In fact, subjects ate up to 50% more when they were eating from a bigger container. The simple reason is that it was more difficult for subjects to monitor how much they were eating.


In dining halls we waste huge amounts of food, without thinking about the role of trays in helping this. If our tray appears too empty, or half full, we may think we did not get enough food. This leads us to get more food than required, which is very often partially wasted at the end. Many universities in the US dropped the use of trays. At Alfred University food and beverage waste was reduced between 30-50%. Plus, without the need to wash and sanitise trays, the use of water and chemical products is reduced.

Indeed, nudging will not save the world and structural changes are required in the area of food production. However, this will take time. In the meanwhile, what can be done is to focus on those individual behaviours that are detrimental for the collectivity. There is a diffused lack of trust (and lack of awareness, too) in the importance of smaller actions, which compounded collectively can either contribute to the resolution of issues or just to their aggravation.