Should we worry about food miles?

As the world meets in Copenhagen this week for the 15th United Nations Climate Change Conference, it was interesting to read that government economic research agency the Australian Bureau of Agricultural and Resource Economics (ABARE) is refuting the widely-held belief that buying locally produced food is always better for the environment and labelling “food miles” a “misleading indicator” of carbon emissions.

The term food miles refers to the idea that food that travels long distances leaves a bigger carbon footprint than locally-produced food, thanks to the fossil fuels required to transport it.

In fact, researchers have found that the carbon footprint of an imported product may still be less than the local equivalent if it is produced more efficiently overseas. The ABARE report reads:

Empirical evidence indicates that food miles is an unreliable indicator of carbon emissions in the food supply chain. For example, in 2006 a major study on the validity of food miles found that New Zealand is substantially more energy efficient, and less carbon intensive, than UK producers in producing and delivering lamb and dairy products to the UK market.

The problem is the fact that the distance food travels is only one factor contributing to its carbon footprint: energy used in the production process, for example to power machinery or heat greenhouses, and fertiliser and pesticide use all play a role. In the example cited in the report, greener farming practices meant that New Zealand produced four times less carbon dioxide delivering lamb and dairy products to UK markets than their British peers, even when the more than 17,000km journey was factored in.

Here in Australia we are, like New Zealand, comparatively “clean and green” but thanks to the country’s sheer size, food often travels vast distances before it reaches its destination.

One grassroots movement that has been gaining in popularity is the “100-mile diet”, so-called because proponents only eat food that is grown within a 100 mile (160km) radius of their home. Good in theory until you consider that staples like sugar, coffee, tea and even milk would be off the menu for most of the population.

In the end food miles is probably one of those concepts to be aware of without being slavishly obsessive about. There are plenty of other good reasons though to eat locally-grown, seasonal produce whenever possible, not least because it usually tastes better and you’ll be supporting regional producers.