Eating fruits and vegetables is better for the planet than meat and cheese. But chips and sugary drinks also have a very low environmental impact: Scientists analyzed some 57,000 products sold in supermarkets in the UK and Ireland, in a large study published Monday by the journal PNAS scientist.
The researchers, who hope their research will enable consumers to shop more sustainably without sacrificing health, also compared their results to the nutritional value of these foods.
So syrups, soft drinks or other fruit juices are among the products sold with the lowest environmental impact (because they mostly consist of water), but their nutritional quality is poor, the study said.
However, researchers believe that the most sustainable products are generally the best from a nutritional standpoint.
This work thus confirms what other studies had already shown by analyzing individual ingredients (fruit, red meat, etc.). What’s new is that the analysis here covers multi-ingredient products (sauces, ready meals, etc.).
The task is difficult because the amount of each ingredient is considered a trade secret and therefore not very detailed: only about 3% of the more than 57,000 products sold by eight food retailers had a fully quantified composition.
The scientists therefore developed an algorithm based on the few known pieces of information to assess the proportion of missing ingredients (in the UK and Ireland, in particular, the components are listed in order of quantity used).
To assess the environmental impact, four factors were taken into account: greenhouse gas emissions, use of limited water resources, land use and aquatic eutrophication (water pollution).
Bread, but also certain cereals, certain ready meals or desserts (cakes, biscuits, etc.) have a relatively low or medium environmental impact.
On the other hand, fish, cheese and meat, especially red meat (lamb, beef) have a strong impact.
“Replacing meat, dairy and eggs with plant-based alternatives can have major environmental benefits”note the authors of the study.
But also “smaller” transitions can help.
For example, beef lasagna, with a strong environmental impact, could be replaced by chicken or pork lasagna, or even vegetarian.
In the future, more knowledge about the dosages and origins of various ingredients would help determine their impact on the environment more accurately, the researchers note.