Blog 

Here is where I share my thoughts, ideas and opinions about the world of nutrition, food and health. I hope you find good sense, helpful guidance and inspiration to eat great healthy food that makes you feel good.

I write regularly for GI News, an online newsletter for 60,000+ Australasian and International subscribers interested in the glycemic index (GI) and associated health topics such as diabetes, weight loss and a healthy heart. It’s a great read. http://www.gisymbol.com/category/gi-news/

 

20 Aug 2013

How will sustainable eating assist in combating climate change?

Posted by Nicole Senior on Tuesday, August 20, 2013

Anthropogenic warming is caused mainly by emissions of greenhouse gases (GHGs), such as carbon dioxide, methane, and nitrous oxide (N2O). Agriculture is a main contributor of methane and N2O: in 2005, 60% of N2O and 50% of methane came from agriculture.

From paddock to plate what we eat influences the production of greenhouse gases. Estimates vary as to the proportion of Greenhouse Gases (GHG) that can be apportioned to food. The Australian government says agriculture is responsible for 16 per cent of Australia’s greenhouse gases1  and transport, manufacturing, packaging, storage, refrigeration and the disposal of waste food and packaging add to the carbon footprint of the food supply. The Australian Conservation Foundation estimates food to constitute 28.3% of the average household’s GHG pollution2

Animal foods are generally more resource intensive or polluting to produce (and fruit & veg flown on planes). In general, larger animals are less efficient at converting feed to food, and produce more waste (eg methane from manure). Ruminants (eg cattle, sheep) emit most CO2 due to enteric fermentation so beef, milk, lamb are high GHG foods. Pork, poultry and kangaroo are more efficient and have lower GHG emissions than beef. Fresh vegetables, cereals and legumes have the lowest emissions. Like many issues within the food and environment sphere, we have to strike a balance between the nutrients we need and the environmental costs of producing them. While some may advocate eliminating meat from the diet, this is not realistic (or enjoyable to many) solution. A more achievable way to reduce GHG emissions and optimize nutrition is to reduce the amount of red meat we eat and focus on improving sustainability of meat production.

The more a food is processed, the higher it’s carbon footprint. Artificial additives and packaging increase the energy input required, but of course these help to improve food safety and reduce food waste so a balance must be struck between eating fresh and processed foods. Eating fresh, local and seasonal requires less transport and storage.

Every kilogram of food waste added to landfill generates the equivalent of a kilogram of greenhouse gases3 so reducing the amount of food we waste is an effective way to reduce our environmental footprint.

Sustainable eating is not simple but we could go a long way by maximising our nutritional bang for our environmental buck by choosing nutrient rich foods, reducing highly processed treats and minimising food waste.

National Greenhouse Accounts. Department of Climate Change. Australian Government, available at http://www.climatechange.gov.au/agriculture/ (Accessed 21/7/2009).

Consuming Australia: Main Findings © 2007, Australian Conservation Foundation, www.acfonline.org.au

Food, garden, packaging and materials. Department of the Environment, Water, Heritage and Arts, Australian Government, available at http://www.environment.gov.au/settlements/gwci/food.html (Accessed 22/7/2009).