Around a dinner table the other evening, food miles were discussed. We know that food miles have given consumers choice and food miles have reduced the cost of food although the environmental cost is still very much up in the air. We only need to look at the UN calculations on shipping emissions to know that. But the real cost of food is moving through the chattering classes and if fuel costs remain high and legislation penalises polutting transporters, and there is good evidence for both, then the real price of food miles will be revised and upwards.

There is little doubt that the best way businesses can help the environment is to be efficient, to think before you consume, use less and reuse, and if you can, what you have use more often. Business might add another dimension and that is to try to source when and where ever it can locally. Call it the 100 mile carbon diet.

What might that mean? It could begin with locally sourced energy and the UK that will probably be off grid. The closer you use energy to its source the more efficient it is.

It might mean purchasing and sourcing goods and services more locally. So don't travel to London for your accountant or big shot lawyer, go and order as many of your supplies locally, asking at the same time how local your supplier sources them. It might mean retninking your office strategy or placing your car fleets more locally.

A 100 mile diet, to reduce, let's say your carbon; fat will make businesses reconfigure. If consumers did the same, we might all find that in sourcing locally, we are not giving up that much but we will, just by default, be using a lot less carbon.

Something to work up and develop? Whose for carbon's equivalent of Weightwatchers?