Rethinking food miles
Buying local produce may not always be as good for the environment as shoppers’ think. There are many reasons why buying locally can be better, from avoiding chemicals and sprays to supporting home-grown businesses.
But sustainability and fewer ’food miles’ - how far food has travelled before you buy it - may not always be one of them.
Enviro-mark chief executive Ann Smith said shoppers need to educate themselves about the entire lifecycle of food.
‘‘Using the term food miles is actually very misleading,’’ she said.
‘‘If you only focus on the food miles then you’re basically not taking everything into account. By saying we’ve got to minimise food miles you could be creating a bigger footprint elsewhere.’’
There’s nothing wrong with locally grown and bought food, she said, but it needed to be in season.
Greenhouse gas emissions were much higher when food was grown in hot houses while out of season.
Smith reported on food miles in a 2006 Lincoln University study. She looked at the total energy used in production and transport found that New Zealand lamb sold in Britain was four times as energy efficient as its local product.
New Zealand dairy was twice as efficient, apples were 40 per cent more efficient and onions 30 per cent more efficient.
A 2008 study from Carnegie Mellon University in Pennsylvania found the majority of greenhouse gases from food were released during the production phase, not transport.
To reduce environmental impact, consumers would do better to swap one day per week’s worth of calories from red meat and dairy products to chicken, fish, eggs, or vegetables.
That would achieve ‘‘more greenhouse gas reduction than buying all locally sourced food’’, the report said. Red meat, for example, was 150 per cent more greenhouse gas intensive than chicken or fish.
Smith said views on importing fresh produce needed to change. ‘‘If it’s bad then why is it good for New Zealand goods to go overseas.’’