Most consumers want to buy food that is smart for their wallet, their health and the environment. And while switching to a vegetarian or vegan diet can reduce the impact on greenhouse gas emissions, it may not be practical or healthy for everyone. Now, researchers at the ACS Environmental Science and Technology Report three ways Americans can reduce the carbon footprint of their food purchases, without requiring drastic dietary changes.
Getting food from farms to people’s plates contributes a large portion of global greenhouse gas emissions. And animals are inefficient at converting the plants they eat into energy, so meat and dairy produce more emissions than fruits, vegetables and grains. Based on that knowledge, previous researchers have offered suggestions for changes that individuals or households can make to reduce emissions generated by food production. However, most of these recommendations are based on the “average American diet.” In reality, not everyone eats the same types or amounts of food, so to account for this variation, Hua Cai and colleagues wanted to assess the actual groceries purchased by US households and identify hotspots of carbon emissions in these purchases.
The researchers analyzed the detailed grocery purchase records of 57,000 US households in 2010 and, for each household, summarized the greenhouse gas emissions for growing and harvesting the food items. Data for packaging and transportation were not included as that information was unavailable Then, they compared the calculations to the emissions that would be created from buying food for a benchmark healthy and sustainable diet.
The team’s analysis found that 71% of homes surveyed could reduce their food carbon footprint, identifying three main ways for consumers. The suggestions are:
- Small families of one or two should buy less food in bulk, which is often more than they eat, and manufacturers should offer cost-effective package sizes.
- Eliminating foods with high caloric content and low nutritional value would reduce total potential emissions by 29%, while also improving health outcomes.
- People should buy less tasty bakery products and ready meals. Although these foods account for relatively low carbon emissions, the large quantities of these items that are purchased add up to significant emissions.
In short, the researchers say these strategies are primary ways people can reduce their food-based carbon footprint in their homes.
The author acknowledges funding from Purdue University Environmental and Ecological Engineering for the award of a Billsland Dissertation Fellowship.