What unsustainable behaviour needs to change:

India has long been one of the world’s most vegetarian-friendly countries, with plant-based eating deeply rooted in cultural and religious traditions. However, rising economic prosperity has driven higher meat consumption. Between 2000 and 2020, India’s per capita meat consumption nearly doubled, fueled by urbanisation, increased disposable income, and evolving food aspirations.

This shift comes at a high environmental cost. Animal agriculture is a major driver of deforestation, water consumption, and greenhouse gas emissions. As India is projected to become the world’s most populous country, its dietary choices will have significant global environmental implications. The challenge is not just awareness but fostering meaningful shifts in daily food habits—a challenge behavioural nudges can help address.

The Green Nudge:

At Gracias Granny, a Mexican restaurant in Mumbai, a real-world experiment tested whether menu nudges could encourage diners to choose more plant-based meals. 

The interventions included:

• Descriptive Enhancements: Adding vivid, appetizing descriptions to plant-based dishes led to a notable increase in plant-based orders, especially in takeaway sales.
• Promotional Offers: A free churro incentive for plant-based meals boosted selection, proving that ‘perceived value’ can be a stronger motivator than sustainability messaging.
• Menu Structuring: Featuring a plant-based „Burrito of the Day“ resulted in 100% of orders from this category being plant-based– without reducing overall sales.

However, not all nudges were successful:

Messaging nudges that highlighted the environmental impact of meat consumption unexpectedly led to a drop in plant-based choices. Instead of motivating change, these messages reinforced existing food habits, showing that positive framing (focusing on taste and value) is far more effective than guilt-based appeals.

These findings demonstrate that subtle, experience-driven nudges—rather than moral arguments—can be a powerful tool for shifting food behaviour toward sustainability.

Do you know of any other nudges that encourage sustainable dining? Feel free to get in touch: hello@green-nudges.com 

From Rashmit Arora, co-founder of Gracias Granny, a Mexican restaurant in Mumbai; Chris Bryant, founder of Bryant Research; Billy Nicholles, Researcher at Bryant Research; and Charlotte Flores, a Food Systems Researcher. Conducted by Bryant Research, this study combines academic insights and real-world restaurant data to identify which menu nudges and promotions encourage plant-based choices—and which do not.

What unsustainable behaviour needs to change:

Compostable packaging—like cups, cutlery, and salad boxes—can be a more sustainable alternative to plastic, but only if disposed of correctly. If placed in general waste or recycling, it can’t be composted and may even contaminate other waste streams.

In UK workplaces using Vegware packaging, research based on the Behaviour Change Wheel (Michie, 2011) identified three key barriers to correct disposal:

• Compostables are difficult to distinguish from conventional plastics;
• Bin signage is often unclear or inconsistent;
• Motivation is low when composting feels abstract or irrelevant.

While closed-loop composting infrastructure is not yet widespread in the UK, it’s steadily growing—particularly in workplaces and community projects. Where these systems exist, correct disposal is essential to unlock their full environmental benefits. Behaviourally-informed interventions can help ensure that infrastructure delivers on its promise.

The Green Nudge:

The research team, in partnership with Hubbub, developed a behaviourally-informed intervention  to improve compostable waste disposal in three UK office canteens. The intervention addressed disposal barriers through a series of targeted nudges:

Bright pink labels with  clear icons and the message “Put in compostables bin” were added to all compostable items;

• Matching pink signage was placed above compost bins;
• A short motivational video explained the benefits of composting in relatable terms;
• Compostable bins were introduced in one of the canteens;
• Managers were briefed to support consistent implementation.

The results: Waste audits by Recorra showed that before the intervention, compostables made up just 32% of bin contents. After one month,this rose to 61% and after two months reached 77% —demonstrating a clear shift in behaviour.

Managers praised the intervention, describing the signage as “amazing.” The findings highlight how consistent visual cues and emotional engagement can significantly improve composting behaviour in workplace settings.

Are you aware of any other nudges that help to keep waste collection streams clean? Feel free to get in touch: hello@green-nudges.com

From Dr Nicola Buckland, a psychologist and Senior Lecturer at the University of Sheffield. This research was conducted in collaboration with colleagues at The University of Sheffield, Dr Sara Bru Garcia, Meghann Matthews, Thomas Webb and Sarah Greenwood, Rosie Sharp from Hubbub, Tom Mockridge from Recorra, and David Dyce MCIWM, Lucy Frankel from Vegware.

What unsustainable behaviour needs to change:

Plastic bags, primarily derived from petroleum products, contribute significantly to environmental pollution and can take up to 1,000 years to decompose. Acknowledging this challenge, the EU aims to reduce annual plastic bag usage to 40 bags per person by 2025. Norway has acted on this through awareness campaigns and price increases, successfully lowering plastic bag consumption from 135 per person in 2022 to 104 in 2024.

However, most households still repurpose plastic shopping bags as bin liners, limiting further reductions. While recyclable bin bags offer a more sustainable alternative, their adoption remains low.

The Green Nudge:

In partnership with a grocery store and funded by the Norwegian Retailers‘ Environment Fund, Nudgelab implemented a series of behavioural interventions to promote sustainable bin bag use:

• Visibility & Convenience: Sustainable bin bags were strategically placed in large containers near checkout areas, making them easy to spot and pick up.
• Cost-Framing Effect: Posters highlighted the cost savings of using sustainable bin bags, reinforcing the perception of a “smarter choice.”
• Increased Friction for Plastic Bags: Plastic bags were stored under self-checkouts, making them less accessible. Additionally, small signs reminded customers of the high cost of plastic bags, further discouraging their use.
• Reframing the Checkout Default: Staff replaced “Do you need a bag?” with “Do you have something to carry your groceries in?”, prompting customers to rethink their need for a plastic bag.

The results: Over the six-week trial, sales of sustainable bin bags increased by 414%, while plastic bag consumption fell by 20%—a stark contrast to the 14% rise in plastic bag use nationwide. These findings confirm that making sustainable choices easier and creating friction for less sustainable options can drive meaningful behaviour change.

However, interventions like this only succeed when integrated into a well-functioning system. In Norway, plastic recycling infrastructure is well-developed, enabling the effective processing of recyclable bin bags. Yet, consumer behaviour remains key—if these bags are not disposed of correctly, they won’t be recycled and could still contribute to environmental pollution. In regions lacking such infrastructure, interventions promoting recyclable alternatives may fail to deliver their intended impact.

Do you know of other nudges promoting sustainable bin bag use? Share your insights or get in touch: hello@green-nudges.com  

From Dr. Irmelin Bergh, a behavioural psychologist and partner at Nudgelab in Norway. She has extensive experience in behaviour change, having worked as a researcher at the University of Oslo and as a strategic consultant at Netlife Design. During her doctoral studies, Dr. Bergh spent time at UC Berkeley and Stanford, gaining unique insights into applying behavioural psychology and “nudging” within major Silicon Valley companies.

What unsustainable behaviour needs to change:

Despite growing awareness of sustainability, plant-based foods continue to face deep-seated stigma. Many consumers dismiss these options without trying them, assuming they are inferior in taste or nutrition. This reinforces a heavy reliance on animal-based products, which significantly contribute to greenhouse gas emissions, land degradation, and water consumption.

Research indicates that “expectation bias” plays a major role in food choices. When individuals perceive plant-based foods as less desirable, they are less likely to consider them—regardless of actual quality. Addressing these psychological barriers is essential for accelerating the transition to a more sustainable food system. Rather than requiring drastic dietary changes, the key lies in making plant-based foods an appealing and natural choice.

The Green Nudge:

A blind taste test experiment was conducted in Thailand using chocolate to remove preconceived notions about plant-based ingredients. Participants sampled two types of chocolate without knowing which one was plant-based and which one was dairy-based.

Here’s how it worked:

1. Participants tasted Chocolate A and rated it out of 5.
2. They repeated the process with Chocolate B.
3. After both chocolates were scored, participants guessed which one was plant-based—before their blindfolds came off, revealing the truth.

The results: the plant-based chocolate was rated slightly higher, receiving an average score of 3.9, compared to 3.6 for the dairy version. While the difference was modest, it challenged common assumptions that plant-based alternatives are inferior in taste.

Several participants expressed genuine surprise when discovering which chocolate was plant-based. Many admitted they wouldn’t have expected to enjoy it as much had they known in advance. This highlights how expectation bias—not actual flavour—is often the biggest hurdle to adopting more sustainable food choices.

Addressing these psychological barriers is essential to accelerating the transition to a more sustainable food system. Rather than requiring drastic dietary changes, the key lies in making plant-based foods feel like an appealing and natural choice.

Know a smart nudge that challenges food-related bias or boosts plant-based choices? We’d love to hear about it: hello@green-nudges.com

What unsustainable behaviour needs to change:

Littering along roadsides is a persistent problem. These spaces, often seen as a ‘no man’s land,’ exist in the transition between inhabited areas and travel routes. Many motorists lack a personal connection to them, making it easier to discard waste from their cars without a second thought. The anonymity of roadside spaces leads to  psychological detachment from responsibility.

This behaviour stems from the ‘tragedy of the commons’—when shared spaces suffer because no single individual feels accountable. Additionally, ‘out of sight, out of mind’ plays a role: once rubbish leaves a car window, it’s no longer the driver’s problem.

The Green Nudge:

To shift this perception, Fama Volat collaborated with a local forester to reframe the roadside as a protected nature reserve. The intervention was simple: a brown UNESCO-style sign declaring the roadside a „Protected Natural Area.“

Why does this work? People litter less in places they perceive as valuable. A nature reserve signals an environment worth protecting, subtly encouraging motorists to keep their trash inside their cars.

The results: In multiple Dutch municipalities, the Protected Roadside sign has led to a more than 50% reduction in litter. The intervention gained media traction and is now being tested in Belgium, where the first municipalities have begun trialling the approach.

By changing how people view roadsides, this intervention turns scattered stretches of land into a collective, nationwide nature reserve—one that we can all help to protect.

Are you aware of any other nudges that help to reduce littering? Feel free to get in touch: hello@green-nudges.com

What unsustainable behaviour needs to change:

The burgeoning meal kit delivery industry offers a unique opportunity to reduce dietary greenhouse gas emissions. However, many consumers habitually select meat-based meals, often overlooking plant-based alternatives. This tendency is influenced by habitual behaviour and default choices, where individuals stick to familiar options without considering more sustainable possibilities. 

Additionally, there’s a concern about compensatory behaviours—for instance, choosing a salad for lunch might lead to indulging in a heavier, meat-based dinner, negating earlier sustainable choices.

The Green Nudge:

To address this, researchers introduced a pop-up message on an online meal kit platform. After customers selected their lunch, but before choosing their dinner, the message highlighted the environmental impact of their choices:

„Did you know that by opting for a plant-based dish, you could save greenhouse gas emissions equal to the energy needed to power your phone for two years? Choosing plant-based reflects a commitment to a more environmentally friendly lifestyle.“

This intervention significantly influenced dinner selections:

• For customers who chose a plant-based lunch, the message reinforced their environmentally friendly self-identity, leading to a 51% increase in plant-based dinner choices.
• For those who selected a meat-based lunch, the message created a sense of cognitive dissonance, highlighting the inconsistency between their choices and the positive identity described. This led to a 27% reduction in meat-based dinner selections.

By leveraging behavioural spillover, this nudge encouraged sustainable choices across meals, showing how a well-timed reminder can reinforce eco-friendly habits.

Do you know of other nudges that promote sustainable food choices? Feel free to comment or get in touch: hello@green-nudges.com

Why Sustainable Fashion Still Isn’t Mainstream:

For many, traditional sustainable fashion can still feel out of reach, often seen as a more expensive or niche option. The affordability and accessibility of fast fashion make it a go-to for those on a budget or with limited resources.

While second-hand shopping provides a sustainable alternative, traditional thrift or vintage stores can feel cluttered, unorganised, and unappealing—more like rummaging through leftovers than an enjoyable shopping experience. This “messy bargain bin” image puts off many consumers who might otherwise choose pre-loved fashion. 

Amid rising living costs and the climate crisis, it’s high time we make sustainable fashion accessible and appealing to all.

The Green Nudge:

A new generation of second-hand fashion stores is changing the game, making pre-loved shopping just as appealing, effortless, and stylish as buying new. Good London, Ada & Albert, and Verso Vintage Shop are leading the way, proving that second-hand doesn’t have to feel second best.

Good London, for example, sits seamlessly between high-end brands in London Bridge Station. Its sleek layout, curated collections, and premium feel make shopping second-hand an aspirational experience—without the waste or high price tags. This shift isn’t just about sustainability; it’s about mainstreaming and elevating pre-loved fashion so that choosing second-hand is the natural, desirable option for everyone—not just those already in the green bubble.

Do you know of other nudges that help mainstream sustainable shopping? Feel free to comment or get in touch: hello@green-nudges.com