Despite the popularity of New Year’s resolutions, scientists have found that post-holiday food shopping decisions don’t necessarily reflect intentions to eat healthier or lose weight.

Scientists from Cornell University tracked resolutions and after-holiday food shopping habits of 207 families. They classified about 20,000 food products as either “healthy” or “less-healthy”. Calories and dollars spent were also tracked.

Analysis of 37 weeks of activity that included the extended winter holiday period and into the new year found that additional food expenditures and calories began about a week prior to Thanksgiving and peaked during Christmas celebrations. Compared to the rest of the year, this increased shopping averaged just over $16 more a week, about $4 of which was spent on healthy foods.

Food expenditures then continued to increase after the holidays to about $25 more a week compared to the average—showing a 24 percent increase. However, $13 of this was spent on healthier foods.

Calorie levels also increased. “Total weekly per-serving calories increased by 440 during the holiday period relative to the baseline period, and nearly 91 percent of this increase was due to additional purchases of the more calorie-dense foods,” the researchers reported.

“Even more intriguing is that contrary to well-intentioned New Year’s resolutions, additional weekly per-serving calories purchased increased to 890 in the post-holiday period relative to the baseline, more than doubling the 440 calorie increase evident in the holiday season,” the researchers observed. Of this, 63 percent of the additional calories were from high-calorie  foods.