Nudge+: Making people reflect improves sustainable dietary choices

What unsustainable behavior needs to change:

We love the variety of food available worldwide, despite inflated and rising prices. We get to enjoy meats our grandparents couldn’t. On the opposite hand, having diverse food choices contributes to enormous carbon emissions and clashes with sustainable climate goals. Hence, why shifting to eco-friendly diets matters.

Changing diets isn’t easy. Instead of strict rules or higher prices, researchers use subtle nudges to gently guide us toward better choices without being overbearing or controlling. However, using these nudges on a wide scale is tough. Sometimes, it raises concerns about whether people are aware they’re being “nudged” to change. Especially with personal choices like diets, some argue it’s not right to push people on what to eat.

The Green Nudge:

To address these challenges, a novel approach in behavioural science, known as “nudge+”, can empower individuals to reflect on their choices and encourage meaningful shifts towards more environmentally friendly behaviours. A nudge+ is a combination of a nudge with an encouragement to think. This modification to the nudge allows people to reflect on their choices and decide whether they want to follow a certain nudge or not.

Designed in this way, a nudge+ makes behaviour change more legitimate, ethical and effective. In a recent publication in “Nature Sustainability”, the authors experimented with 3,074 UK participants to validate their proposition that human agency enhances the effectiveness of behaviour change tools.

Four nudge+ interventions were used: Two combined “the green default” or “carbon-labelled” nudge with transparent information disclosure. The other two nudges partially integrated the „think“ aspect with the green default; allowing pledges before or after defaulting to the green menu. The nudge+ primarily prompted a pledge without deep menu deliberation. Once committed to eco-friendly eating, it automatically directed individuals to the green menu, simplifying their intention execution.

The result: All interventions effectively increased intentions to choose sustainable foods. Notably, the most effective results were achieved by promoting reflection on dietary preferences before guiding individuals towards greener diet choices. The addition of a pledge before implementing the default nudge, as seen in the nudge+ approach, led to a 40% reduction in emissions resulting from intended meal selections.