The British public eat over 11.5bn sandwiches every year, spending around £8bn in the process, according to the British Sandwich Association (yes, there really is such a thing).
But whether your choice is the classic cheese and tomato or the heartier chicken and bacon, your sarnie option could have more riding on it than you think.
Researchers from the University of Manchester carried out the first ever study into the carbon footprint of sandwiches, for both ready-made and home-made products.
More than 40 different sandwich recipes were studied, with researchers taking into consideration the whole life-cycle of the sandwich from farming the raw ingredients to packaging and transportation as well as refrigeration and food waste.
The biggest carbon footprint belonged to the ready-made All Day Breakfast. Stuffed with egg, sausage and bacon, the packed sandwich generates 1,441g of CO2 equivalent. According to our calculations, that's the equivalent of driving an average hatchback for nearly eight miles.
The samples were taken from a range of supermarkets where “the recipes were quite similar," according to the paper’s author, Adisa Azapagic.
Some of the worst culprits, all over 1000g of CO2 equivalent each, were roast chicken and bacon (1,029g), ham and salad (1,119.1g), and cheese and tomato (1,067.3g). Prawn and mayonnaise produced a whopping 1,254.7g of CO2.
The report shows that sandwiches containing meat products have the largest carbon footprint. The study concludes by suggesting we should leave out certain ingredients from our sandwiches such as meat, cheese, and tomato.
Tomatoes?! They're grown in the UK, right? Well, Adisa explains: "The results indicate that the largest contributor to the carbon footprint of a sandwich is the agricultural production and processing of ingredients. Tomatoes in this country are grown in greenhouses which are heated. Burning fossil fuels to generate the heat produces GHG (Greenhouse gasses) emissions, which then contribute to a high carbon footprint of tomatoes.
“For meat products, the carbon footprint is higher because of the greenhouse gas emissions associated with their rearing, which includes the emissions to produce the feed and to process the meat."
Time to cut out sandwiches all together then? Not quite.
Adisa suggests making sandwiches at home instead to reduce a sarnie’s carbon footprint.
“You could consider making a home-made sandwich as our results show that like-for-like, the carbon footprint is half that of the commercial sandwich.”
The study also found the biggest chance of reducing the humble sandwich's carbon footprint further was eliminating post-consumer waste (though the study also notes how difficult this change in "consumer behaviour" would be).
Adisa said: “Given that sandwiches are a staple of the British diet as well as their significant market share in the food sector, it is important to understand the contribution from this sector to the emissions of greenhouse gases.
“For example, consuming 11.5bn sandwiches annually in the UK generates, on average, 9.5m tonnes of CO2, equivalent to the annual use of 8.6m cars.”
Perhaps Clive, though, is overreacting slightly?
However, the sandwich isn’t the only British food staple that is damaging the environment.
In Britain, 2.5bn disposable coffee cups are thrown away each year, many ending up in landfill.
Researchers at Cardiff University found that charging customers an extra 25p for every coffee cup would prevent 300 million cups being used, with MPs urging the government to implement this “latte levy”.
No coffee, no sandwiches - will we even survive the next lunch hour?