ABC News December 25, 2014

Why Your Holiday Weight Gain Sticks Around All Year

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Those New Year’s resolutions to slim down may be the ironic reason most people don’t shed the extra weight they gain during the holidays, according to a new Cornell University investigation.

The average person packs on just under a pound between Thanksgiving and New Year’s. But those few extra ounces tend to stick to the waistline for years, studies show. Over the course of a lifetime, this slight seasonal weight gain contributes to “creeping obesity” and a host of other health problems.

The new research, published into today’s PLOS One journal, confirms that people generally do consume more calories than usual as they celebrate the holidays with parties, buffets and large family feasts. However, while the average food shopper bought three times the amount of healthier foods like fruits and vegetables after the New Year, they didn’t back down on junk food purchases, explained Brain Wansink, head of Cornell’s Food and Brand Lab and the study’s lead author.

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“In an effort to eat healthier they wind up spending $20 more on food per shopping trip and eating 14 percent more calories than before the start of the holidays,” Wansink said.

Among the 207 families the researchers followed throughout the 30-week study, most purchased a weekly average of 389 additional calories per serving than before the holidays, Wansink pointed out. After the holidays, this jumped to an additional 793 calories per serving above baseline, with more than a third of the excess calories coming from healthier foods.

Wansink said that consumers seem to have good intentions but don’t always fully commit to weight-loss goals.

“Our study showed that consumption of healthy foods increased but consumption of non-healthy foods remained constant,” Wansink pointed out. “Even when people recognize that making a change would be best, they may have trouble following through on those changes.”

Wansink said this study only shows what people purchased, not what they ate. And, since the research didn’t look at a full year, it’s only clear that the higher-calorie purchases persisted through Super Bowl weekend.

“Maybe when winter ends and people start gearing up for bikini season, they get a little more serious about losing weight,” he said. “But it also could be that they continue to spend more and eat more all year long and that consumption continues to rise every single year.”