Scientists are calling on the catering industry to provide more “nutritionally optimal sustainable options” after it was revealed sandwiches with the lowest environmental impact contain less iron and vitamin B12.
Researchers from the University of Sheffield’s Grantham Centre for Sustainable Futures and Institute for Sustainable Food found that even though high-impact sandwiches and beverages tended to have more calories, protein, carbohydrates, total fat, saturated fat, iron and sugars, the more sustainable choices were lower in micronutrients because they did not contain animal products.
The study, published in Sustainability, found that beef sandwiches and milk-based drinks had the highest environmental impact – based on their water use and greenhouse gas emissions – and vegan options the lowest.
Most of the vegetarian options contained cheese, which was found to be more damaging for the environment than chicken or eggs – suggesting that vegetarian sandwiches aren’t always more environmentally friendly than meat.
When it comes to drinks, the study showed that those containing milk, cocoa or coffee had the highest environmental impact. Choosing a milk-based drink over a sugar-sweetened one could therefore be better for health but less environmentally friendly, highlighting possible tensions between nutrition and sustainability.
Sandwiches comprise a large proportion of food consumed outside the home in the UK, with four billion pre-packed sandwiches sold in 2018 – while the non-alcoholic drinks market continues to grow, with sales of coffee products alone generating an estimated turnover of £3.2 billion.
Dr Fiona Graham from the Institute for Sustainable Food, a Research Associate at the University of Sheffield’s School of Health and Related Research (ScHARR), was the lead author of the study. She said: “As the climate emergency accelerates, it’s crucial that we shift towards more sustainable diets – but our study found that cafes provided fewer low impact options to choose from and those available contained fewer important micronutrients.
“There is huge potential for more plant-based diets to tackle the climate crisis and improve public health – but the catering industry has a responsibility to offer more nutritious options, so people can more easily make healthy and environmentally sustainable choices.
“I’m pleased to see the University of Sheffield is taking this research into account as it develops its sustainability strategy.”