Comparing the environmental footprints of apple and orange (or beef) production is relatively straightforward, but these calculations become very difficult when the food contains multiple ingredients. Until now, there has been no good way to determine the impact of such foods, but the Oxford team recently found that all (edible) sustainability indicators you might find in your local grocery store. published some of the first studies to develop
Beyond estimating the sustainability of the approach, the Oxford team cross-referenced their results with the standard nutrition index NutriScore. This turned out to be many “win-wins” for the food to be sustainable and nutritious, although there were some notable exceptions. , this method provides new metrics for consumers, retailers and producers to make more informed choices.
secret recipe
One of the biggest hurdles in calculating the sustainability of multi-ingredient foods is that producers rarely have to list the amount of each ingredient they use in their products. Quite the opposite. These details are often kept strictly confidential as trade secrets.
However, some countries, such as Ireland and the UK, publish at least part of this information, namely the percentages of certain key ingredients. Researchers from the Livestock, Environment and People (LEAP) program and the University of Oxford’s Oxford Population Health have used these details (from the FooDB resource) to identify ingredients in similar products, including over 57,000 foods that represent nearly everything. We estimated the proportion of of UK and Irish supermarket food and beverages.
Once ingredient estimates were obtained, the HESTIA environmental database was used to calculate the overall inventory impact. The team developed a metric that combined four main impacts: greenhouse gas emissions, land use, water stress, and the potential to cause toxic algal blooms in downstream water bodies (i.e., potential for eutrophication). We calculated an environmental score for each food, including
As a final step, they cross-referenced sustainability results using a commonly used nutrition index called NutriScore. It ranks foods based on “good” nutrients, such as protein, fiber, fruit/vegetable content, and healthy oils, and “bad” nutrients, such as calories, fat, salt and sugar.
“We use NutriScore because it is used fairly widely in many countries around the world, and many researchers are familiar with the concepts behind it,” says Michael, lead author at the University of Oxford. says Clark. “The whole premise was developed to be applied at the population level to yield better health outcomes.
win win
When researchers tested their method on products containing known ingredients, they found it worked well. It was almost identical.
“Our findings weren’t all that surprising,” Clark said. “For at least the last decade, certain commodities (generally beef and sheep) have had a higher impact, while certain commodities like plant-based foods (with some exceptions such as chocolate and coffee) have had a lower impact. The evidence is growing.)”
In general, meat, cheese, fish, and anything made with these ingredients had the greatest estimated impact.As expected, anything based on fruits, grains, or vegetables ranked lower. Combined with NutriScore, it creates a clear win-win product, like whole grain foods and produce that is nutritious and environmentally friendly. Potato chips also performed particularly well due to their high “vegetable” content. Other foods, such as nuts, fish and meat, were nutritious but had a relatively high environmental impact.
work in progress
The research team hopes their research will be a starting point for indicators that consumers, producers and retailers can use to make more sustainable choices. Where and how ingredients are produced is another factor that can significantly change the impact and is largely undisclosed. not.
“I hope this is the beginning of a longer journey and an opportunity to work together to develop something mutually beneficial,” Clark said. “The most exciting part is applying it. We now have mechanisms that allow people to compare the range of foods they produce, sell or buy, and make informed decisions about the impact of these choices.” can do. “
PNAS, 2022. DOI: 10.1073/pnas.2120584119
