First, the researchers found that shoppers spend 15% more on food during the holiday season (Thanksgiving to New Year’s) and only about 25% of that additional food is healthy. This means that during the holidays we tend to buy more junk food–not a big surprise. “What was surprising, was the second finding of the study” says lead author Lizzy Pope, who led the study as a post-doctoral student at Cornell, and recently joined the University of Vermont’s Dept. of Nutrition and Food Sciences, “After the New Year, shoppers continued to purchase a greater amount of food and while more healthy food did make it into their carts, they continued to buy the less-healthy items too!” After the New Year, shoppers actually took home 9% more calories than they did during the holidays!
For this study, 207 households were recruited to participate in a 7 month study to track grocery store spending behaviors. These households shopped at one of two participating grocery stores in upstate New York. Grocery purchase data were collected from July 2010 to March 2011. To capture the impact of holiday shopping, the data were divided into three time periods. July to Thanksgiving was considered baseline spending (how much the average shopper regularly spends per week on groceries) Thanksgiving to New Years was considered the holiday season, and New Years to March the post-holiday period. The researchers then compared these three time periods to find differences in shopping patterns. “We wanted to see how New Year’s resolutions and the end of the ‘holiday season’ impact grocery shopping habits, both how much food people buy and how many calories the foods contain,” explains co-author David Just, Cornell University. Foods were categorized as healthy or less-healthy based on a nutritional rating system used by the participating grocery stores.
“Despite New Year’s resolutions to eat healthier, people tend to hang on to those unhealthy holiday favorites and keep buying them in the New Year,” says co-author Drew Hanks, Ohio State University. “What we recommend based on these findings is instead of just adding healthy foods to your cart, substitute the less healthy foods for fresh produce and other nutrient rich foods–the calories will add up slower and you’ll be more likely to meet your resolutions and shed those unwanted pounds.”
Pope, Lizzy, Andrew Hanks, David Just and Brian Wansink (2014). New Year’s Res-Illusions: Food Shopping in the New Year Competes with Healthy Intentions. PLOS ONE. DOI: 10.1371/journal.pone.0110561