The quick answer to the question of where your lunch comes from - the sandwich trolley - doesn't cut the mustard nowadays. Food miles are a big concern in these carbon-conscious times, no surprise when 95% of the fruit and half the veg sold in the UK is imported.
Defra reports that food miles rose by 15% between 1992 and 2002 - that includes flying in mange-tout from Kenya to satisfy our year-round taste for 'seasonal' veg, and sending produce round the country to package it before it goes up on the shelves. But food miles is a flawed concept: the food production process pollutes in ways other than transport, and it's hard to equate a bag of spuds travelling a mile packed into an HGV with one on the back seat of a car coming back from the supermarket. Still, when the average person travels an estimated 135 miles by car every year to shop for grub, it's clear we can all do something.
Being more aware is a good start. Walk to the nearest farmer's market in your lunch break and learn from the people who grow it. Fresh food will be better for you anyway, and should taste nicer. Visit www.eattheseasons.co.uk to learn what's in season and buy food along seasonal lines, which will help ease our reliance on energy. If you really get into it, you can always grow your own. Time to pester for that office allotment.
Four out of 10 - this will mean changing some habits. Nine, though, for flexing your own green fingers.
Dave Waller is MT's resident eco-prefect.