A team of researchers from Oxford University, UK, assessed the environmental impact of 57,000 food products in the UK and Ireland. The study was published in the journal PNAS and showed that most plant-based products have a lower impact than meat-based foods.
The authors compare the impact of meat and meat alternative food items, such as plant-based burgers and sausages, to find that many meat alternatives have less than a fifth of the environmental impact of meat-based products. This study allows consumers, retailers, and policy-makers to make informed decisions about the food and drinks they consume.
“By estimating the environmental impact of food and drink products in a standardised way, we have taken a significant first step towards providing information that could enable informed decision-making. We still need to find how best to communicate this information effectively in order to shift behaviour towards more sustainable outcomes, but assessing the impact of products is an important step forward,” said lead author Dr. Michael Clark.
Most UK consumers want to make sustainable decisions to protect the environment, and many food corporations are setting net zero goals for the next few years. However, there is a lack of detailed and accurate information about the impact of different foods on the environment. This study, led by researchers at the Oxford Population Health and Livestock, Environment and People (LEAP) programme, used publicly available information to estimate the environmental impact of 57,000 different products sold in supermarkets across the UK and Ireland.
The study included greenhouse emissions, land use, water stress, and the potential to damage bodies of water. The team then combined these results into a single estimate score per 100g of product.
“This work is very exciting. For the first time, we have a transparent and comparable method for assessing the environmental footprint of multi-ingredient processed foods. These types of foods make up most of the supermarket shopping we do, but until now, there was no way of directly comparing their impact on the environment,” said Professor Peter Scarborough, Oxford Professor of Population Health. “This work could support tools that help consumers make more environmentally sustainable food purchasing decisions. More importantly, it could prompt retailers and food manufacturers to reduce the environmental impact of the food supply, thereby making it easier for all of us to have healthier, more sustainable diets.”
The results showed that products made of fruits, vegetables, sugar, and flour, such as soups, salads, bread, and many breakfast cereals, have a low impact; while those made of meat, fish and cheese have a much higher impact. Dried products like jerky and biltong — which are made with more than 100g of fresh meat — have the highest impact.
Despite these results, there were significant variations within the same products, particularly in products such as biscuits and pesto sauces, and in some cases, the differences were considerable. The authors defend this is the type of information the consumers need to know, which may help shift their behaviour towards more sustainable foods without necessarily changing their favourite items.
In addition, in terms of nutritional value, products with a lower impact also tended to be more nutritious. The most notable exception to this rule includes sugary drinks, which have a low impact and nutritional value.
“An important aspect of the study was linking the environmental impacts of composite foods with the nutritional quality, showing some of the synergies and trade-offs between different parameters. Using this new method, manufacturers can reduce the environmental impact while ensuring a high nutritional quality of products,” said Jennie Macdiarmid, Professor of Sustainable Nutrition and Health at the Rowett Institute, University of Aberdeen.
The study relies on data from foodDB, a database at the University of Oxford that collects and processes information for all food and drink products available in 12 online supermarkets in the UK and Ireland. The researchers also analysed 570 studies looking at the environmental impact of different foods covering over 38,000 farms from around the world.
“Our method fills an information gap on the environmental impacts of multi-ingredient foods. The algorithms we developed can estimate the percentage contribution of each individual ingredient within a product and match those ingredients to existing environmental impact databases. Applying this methodology to generate impact scores for large numbers of products, we illustrated how this can be used to derive quantifiable insight on the sustainability of those products and their relationship to their nutritional quality,” concluded Dr. Richie Harrington, head of foodDB.
Clark M, Springmann M, Rayner M, at el. (2022) Estimating the environmental impacts of 57,000 food products. PNAS, 119 (33) e2120584119, https://doi.org/10.1073/pnas.2120584119