Your New Year's resolve has taken hold, and your grocery cart has all the kale, cauliflower, and quinoa it can hold. But that doesn't mean you're set up to slim down, a new study suggests.

New research published in the journal PLOS ONE found that people buy about twice as many calories per serving of food in the first three months of the year than they do during the holiday months, despite all well-intentioned efforts to cut back in the New Year.

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To reach their findings, researchers recorded the grocery purchases of more than 200 households in New York over seven months, splitting the data into three time periods. The first spanned from July to Thanksgiving, then Thanksgiving to New Year’s (designated as the holiday period), and finally, New Year’s to March. From there, they divided the groceries into healthy or less healthy groups based on a nutritional rating system.

While people purchased more than eight times the amount of healthy calories in the New Year compared to during the holiday season, they didn’t cut back on the unhealthy foods at all—so caloric spending overall increased by 160 calories per serving.

“People start the New Year with good intentions to eat better,” said Lizzy Pope, PhD, lead author of the study, in a press release. “They do pick out more healthy items, but they also keep buying higher levels of less-healthy holiday favorites. So their grocery baskets contain more calories than any other time of the year we tracked.”

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Compared to the baseline period from July to Thanksgiving, the households packed on a whopping 890 extra calories during the New Year's resolution season, up from the 440 calories they added over the holidays.

The researchers believe that people have trouble letting go of their favorite holiday foods once the season passes, but still try to make up for it by throwing in all the salads and green juices they think they should be eating.

“Despite resolutions to eat more healthfully after New Year’s, consumers may adjust to a new 'status quo' of increased less-healthy food purchasing during the holidays, and dubiously fulfill their New Year’s resolutions by spending more on healthy foods,” researchers wrote in the study.

So while those post-Christmas sales on peppermint bark, chocolate Santas, and red and green M&M’s are incredibly tempting, work on sticking to your shopping list to keep to your New Year’s resolutions. And remember, never shop when you're hungry.

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