Buying less junk food can lower households’ potential emissions by 29%, study finds

Dive Brief:

• Americans could reduce their carbon footprint by 29% by purchasing less food with high calorie counts and low nutritional value, such as candy, soda, and packaged snacks, according to a new study from Purdue University, published by the American Chemical Society. Lowering those purchase amounts leads to “as much as, if not more” carbon emissions reductions than a change in diet, the study said.
• Researchers examined the grocery purchase records of over 57,000 U.S. homes and totaled the greenhouse gas emissions required to grow and harvest the items. After this, they compared the emissions totals with that which would result from only purchasing foods that make up “a healthy and sustainable diet.” They found that 71% of homes could lower their carbon footprint through their food purchases.
• As sustainable purchasing increases among consumers, studies such as this bring greater focus on emissions caused by packaged foods and give people another reason to cut down on sweets and snacks.

Dive Insight:

Dr. Hua Cai, a Purdue professor and the lead researcher on the study, recommended smaller households of one or two purchase less bulk-quantity food because it often results in more food that goes to waste.

For foods like savory bakery products and ready-made foods, it’s often not growing the food itself that produces a higher carbon footprint, but the amounts purchased that lead to a negative environmental impact. By lowering these quantities, a household can achieve two-thirds of the carbon emission reduction potentials laid out in the United Nations’ Sustainable Development Goals, according to Cai.

“Small households are purchasing more food items than larger households, which means they’re probably buying or consuming more than they need,” Cai said.

Researchers examined the “cradle-to-farm-gate” carbon footprints of 83 different food items through assessing the foods’ life cycles. Then it calculated the total carbon emissions required to grow it.

The number of people who make purchases with sustainability in mind increased during the pandemic. Eleven percent of those surveyed by Kearney in 2020 said that they have shifted their purchases in the last year based on a desire to have less of a negative environmental impact. The better-for-you junk food segment has also been on the rise in recent years, as consumers attempt to integrate healthier versions of their favorite snacks into their diet. 

People have also, in general, moved more toward healthier foods and care more about branding like clean labels ever since the pandemic. A study by the International Food Information Council found 73% of respondents said they are confident they can identify healthy foods from their packaging. 

One caveat to the data pointed out in the study is that researchers could not account for emissions caused by packaging and transporting foods, as that data was not readily available. Cai and her team said that they wanted to base their recommendations on an “average American diet.” They said the strategies recommended in the study are intended to help people identify initial ways to reduce their carbon footprint.