Accounts for energy use in agriculture, fertilisers, food transport, processing, storage, retail and catering. Also includes methane and nitrous oxides from animal, animal wastes and agricultural soil, and notional credit for soil carbon take-up in organic farms.
Start with a base annual score of 2000kg (typical British diet, 2400 kcal/day, 38% animal-based); 2250kg (serious meat eaters, 50% animal diet); 1400kg (lacto-vegetarians) or 1000kg (vegans).
If you only eat organically produced food subtract 50% from this score.
About 75% of UK food is imported and/or processed (including frozen & canned). If nearly all of your food is processed and/or imported add 100kg to your figure so far. But if very little of your food is processed and/or imported subtract 400kg.
About 25% of meals in the UK are eaten away from home. If you hardly ever eat in restaurants or canteens subtract 100kg from your figure so far. But if you eat half your meals in restaurants or canteens add 100kg.
To be really honest with yourself, if you exercise for ½ hour a day (which, of course, we all should be doing!), you need to add 8% to your score so far for the extra calories you are eating. Don't be deterred by this: if you are walking or cycling when you would otherwise be driving, the planet is still much better off!
Your food score