Claudio, you were one of the first to provide reliable figures on food waste in Switzerland – at a time when hardly anyone was interested in the issue. What drove you back then?
I remember one very specific moment: I was standing outside a bakery shortly after closing time and saw edible goods being thrown away. It wasn’t a spectacular moment, but it stuck with me. It suddenly dawned on me: If this is already evident at a single business, the total across the entire value chain must be enormous. At the same time, there was hardly any reliable data available for Switzerland back then. As an environmental scientist, that was the point where I thought: here, research can shed light on something that has previously been in the shadows – and thereby bring about change.
Which milestones on your food waste journey are you particularly pleased about?
I’m particularly pleased that food waste is no longer just a niche topic. At the latest Focus Food Save event organised by United Against Waste, around 190 people from business, academia, government, the hospitality sector, start-ups and NGOs came together – and with a very solution-oriented approach. foodwaste.ch has also developed significantly: Today, a professional team is working to disseminate knowledge widely and implement concrete projects. Another important step is the National Week Against Food Waste in September 2026, which foodwaste.ch and United Against Waste are coordinating jointly and in which over 40 organisations are participating as advocates. And from a technical perspective, it is a major step forward that we now have very good measurement data with high market coverage in the retail sector. Without data, food waste remains an abstract concept; with data, it becomes manageable.
When it comes to climate protection, many people think first of all of transport or energy. Why should food waste be just as high on the agenda?
Because there is hardly any other area where we can achieve so much with comparatively simple measures. Food accounts for around a quarter to almost a third of our ecological footprint, and a significant proportion of this is linked to avoidable food loss. At the same time, everyone can make an immediate contribution: planning better, storing food properly, using up leftovers, and understanding use-by dates correctly. Another advantage is that we often reach consensus on food waste more quickly than on other environmental issues. Nobody likes to produce food only for it to end up in the bin. And those who start to think about moderation and appreciation when it comes to food often apply this mindset to other areas of consumption as well.
Food waste is a serious climate problem.
Yes, and it’s also a resource problem. To produce food, we need soil, water, energy, fertiliser, labour, transport, refrigeration and packaging. In the case of animal products, there are also additional environmental impacts arising from production. If such food is not eaten in the end, we lose not only the product itself, but all the resources that went into it.
What’s particularly distressing is that part of the environmental impact arises within a system that’s already under pressure, and yet we don’t even make use of the end result. That’s why avoiding food waste is one of the most obvious measures for climate protection.
The target of halving food waste by 2030 is enshrined in Swiss law. Nevertheless, progress has been slow. Why is that?
It is not because nobody wants to do anything. But raising awareness takes time, repetition and coordination. It is precisely for this that the budget is often lacking. Yet this money would be very well spent. In the UK, preventable food waste in households fell by 21 per cent between 2007 and 2012. The financial impact was enormous: for every pound invested in reducing food waste, households and the public sector together saved around 250 pounds. The results are even more evident in West London: six local authorities reduced household food waste by 15 per cent within six months. For every pound invested, the local authorities saved eight pounds in disposal costs alone; households saved a further 84 pounds because they bought less food unnecessarily.
For companies, there is a second consideration: many measures are economically viable, but one must first measure, understand the causes and change processes. This requires an initial investment. However, it is precisely here that international experience demonstrates a very clear business case. An analysis of nearly 1,200 sites across more than 700 companies in 17 countries shows that 99 per cent achieved a positive return on investment, with the median benefit amounting to 14 times the investment. In other words: for every franc invested in reducing food waste, the median return is around 14 francs.
Nevertheless, individual companies often proceed cautiously because they face competition. If a retailer bakes less bread an hour before closing time or displays yesterday’s bread more prominently, this can cost them customers in the short term. If the whole sector adopts such solutions collectively, it becomes a win-win situation. This is precisely why, alongside raising awareness, binding industry solutions are needed. Switzerland has made progress, but not at the pace required to halve food waste by 2030. The momentum now needs to be significantly increased.
Where do you see the greatest potential for achieving this target after all: politically, economically or socially?
All three levels are needed, but above all they must be better coordinated. Politically, more funding is needed for raising awareness, education and information, as well as clear incentives or more binding requirements where voluntary measures are not enough. Economically, sectors must act collectively so that individual companies do not face competitive disadvantages. In agriculture, we need better data to make losses visible and comparable in the first place. And on a societal level, it’s about embedding simple routines into everyday life: shopping mindfully, keeping an eye on the fridge and food stocks, using up leftovers, and interpreting best-before dates correctly. The greatest lever for change is not a single measure, but the interplay of all these factors.
Are there any countries that are significantly further ahead than Switzerland when it comes to food waste, and what could we learn from them?
In certain areas, yes. Denmark excels at raising public awareness and at communicating the issue of food waste in a positive and relatable way. The UK began measuring household waste very early on and systematically, and has developed campaigns such as ‘Love Food Hate Waste’. France has attracted international attention with binding rules against the disposal of edible food in the retail sector. The EU, too, is now moving more strongly towards binding reduction targets.
At the same time, Switzerland is ahead in other respects: in highly sophisticated monitoring – including by-products from the processing industry – and in collaboration along the value chain. So we shouldn’t simply copy others, but look very closely at which measures work where.
What concrete steps can households take? And putting the climate argument aside for a moment: how much money can actually be saved as a result?
For Swiss households, the sums involved are significant: it could amount to around 600 francs per person per year.
The key steps are simple.
- Shop smart – that means planning ahead, checking your stock and not jumping at every special offer.
- Store food properly so that it stays edible for longer.
- Understand best-before dates correctly. A best-before date is not a ‘throw-away’ date.
- Cook creatively and make the most of leftovers, for example by toasting yesterday’s bread or turning it into new dishes.
- Share the joy of food and ask for leftovers to be packed up when eating out, or discuss good solutions with those around you.
We can also help the system by buying misshapen vegetables, accepting yesterday’s bread, trying products from by-products, and letting retailers know that we don’t expect shelves to be fully stocked right up until closing time.
What will you be focusing on over the coming months, and what motivates you most personally in this work?
One key focus remains the national monitoring of food waste in Switzerland. We need to know where we stand; otherwise, we cannot assess which measures are effective. I’m also involved in the European Horizon project GreenGrocer, where we’re pooling knowledge on sustainability in food systems, environmental impacts, processing and wastage so that decisions in politics, business and society can be better informed. And alongside my work at the ZHAW, I continue to be involved on a project-by-project basis with foodwaste.ch.
What drives me personally is collaboration: with companies, industries, the federal government, start-ups, the media, students and highly motivated people. Food waste is a problem, but one for which solutions are incredibly within reach. That’s what makes the work worthwhile.
