If there's two things British people love - it's cars and sandwiches. No surprise, then, that University of Manchester researchers that have equated CO2 emissions of UK sandwich consumption with the pollution caused by cars.

Annual sandwich consumption in the UK has the same economic impact as 8.6m cars, say the boffins at Manchester.

Researchers say the 11.5bn sandwiches eaten each year create the equivalent of 9.5 million tonnes of CO2 - about the amount produced by "the annual use of 8.6 million cars".

That's a lot of cheese and pickle sandwiches.

And All Day Breakfast sarnies, which generate 1,441 grams of CO2 eq each, have the largest carbon footprint.

Chomping down on an All Day Brekkie sandwich is the same as driving a car for 12 miles, although arguably more fun.

Sandwiches with sausage, ham, bacon cheese, tomato or prawns also created a lot of carbon emissions, according to the publishers.

In terms of ready-made sandwiches, egg and cress was the least bad offender, generating 730g CO2.

So what's the solution? Researchers say that making sandwiches at home cuts sarnie CO2 in half.

According to the publication, "The carbon footprint of the most popular homemade sandwich (ham & cheese) varies from 399-843g CO2 eq per sandwich, depending on the recipe."

Or, if you really want that All Day Breakfast supermarket sandwich, you might think about making up for it by leaving the car at home and travelling on foot or by bicycle.