"CRUMBS" was my first thought when I read a tantalising piece in this paper. It said eating sandwiches in the UK for a year produced more CO2 than eight million cars, about a quarter of UK’s total.

It’s really just a reminder that everything we take for granted produces CO2, and the daily 12 million loaves we eat are a very good example of not understanding that just getting through the day has a serious impact on the climate. It’s only by considering what’s involved, from start to finish will we understand why this is so.

The sliced loaf starts with all the heavy mechanical work ploughing and harrowing the fields. Then the manufacture and spreading of ammonium nitrate fertiliser, responsible for half the CO2 emissions, as well as some nitrous oxide, which is 300 times more powerful. Next the harvesting, manufacture and distribution explain why bread produces so much.

Each loaf needs the wheat from almost a square metre of land before being mechanically harvested, and taken for milling to make the flour. Additionally baking. produces about ten percent of the CO2, then packaging (three percent) before delivery to the shops, using CO2 emitting wagons, and then toast.

Everything we use, and eat, produces climate change gases, carbon dioxide, methane and nitrous oxide in some measure. The figure for bread would be even higher if the wheat came from France, Germany, or Canada, though we produce three quarters of what we need ourselves.

Bread is just a straightforward example of the fact that everything we do, harvest or manufacture will have a climate change gas impact, and the same could be said about clothing, or furniture, or road and house building, or power stations, or schools and we can’t do without these.

However we’ll still live without large cars, overseas flights, and out of season foods.

So cut them out.