Op-Ed: As if you didn’t know: Here’s proof the holidays make it hard to eat right

“There’s one thing that’s for sure — I’m not dieting this month!” my Zumba instructor said, right before she added, “So I’m going to be working you extra hard!”

Even people who make a living out of being examples of fitness treat the days from Thanksgiving to New Year’s as a write-off. We are all encouraged to eat our favorites, and if you dare mention you’re trying to curb your carb enthusiasm around Hanukkah, Christmas or New Year’s, you’re more likely to be chastised than supported. Even without that kind of persuasion, a variety of subtle psychological, sensory and social influences make it hard to eat right during the holidays.

First, we tend to be around many more people than usual when we eat. Research by John de Castro, an expert on human eating habits, showed that the amount we eat increases with the number of people we’re eating with, especially if they’re friends; from 33% with just one pal, to almost twice as much with seven or more buddies. And it gets worse if you’re surrounded by visiting relatives or co-workers who stress you out. A number of studies have found that comfort food eases anxiety.

Unfortunately, pecan pie and mashed potatoes are even more alluring and satisfying if you generally have good relationships with people. Studies led by Jordan Troisi, a social psychologist at the University of the South, have found that for people who are “securely attached” — who had loving trusting relationships with their primary caregivers as children — treats can act as surrogates for absent loved ones during times of stress.

Another holiday pitfall: taking breaks from socializing by sitting in front of a screen, maybe watching “It’s a Wonderful Life” yet again or bingeing on “Stranger Things.” Screen time has been proven to lead to weight gain. In a study of nearly 3,500 Australians, people who watched 2.5 to 4 hours of TV a day were twice as likely to be overweight compared with people who watched an hour or less, and watching even more quadrupled the chances that the person was obese.

It’s also probably the case that your holiday screen time will be accompanied by a plate of cookies, a bowl of cashew clusters or a tray of crackers and cheese within arm’s reach. The closer food is to you, the more likely it is to disappear. Studies have shown that office workers eat many more candies when the candy tin is on their desks than when it is a mere 6.5 feet away, students eat more ice cream when the cooler lid is left open, and everyone goes in for more servings the closer they are seated to the all-you-can-eat buffet.

On the bright side, research has also shown that people eat more fruits and vegetables and drink more water when it is easily visible and accessible, so try replacing the cashew clusters with carrot sticks.

And if you can’t resist TV, at least think twice about your sports intake: A major study in 2013 reported that when a committed football fan sees a losing game, especially if it’s a close game against a worthy rival, consumption of high-calorie, high-fat, processed foods goes up as much as 28% the next day. (It’s another example of the comfort food mood-soothing strategy.) However, if your team wins, you’re more likely to eat healthier food — the same study found that happy fans ate 16% less comfort food than usual the day after a glorious victory.

Other lures come from the environment. At a sit-down holiday meal or party, the variety of food is exponentially higher than usual: ham, turkey and roast beef; more salads and vegetable sides than there are on an Applebee’s menu; a dizzying array of desserts. When we’re exposed to variety, we eat much more than when the choices are limited. It’s true even if the variety is a minor change in color. Studies show that after snacking on your favorite-colored M&M’s until you’ve had enough, you’ll start eating them again if you’re offered another color.

There are a few ways to combat the holiday food over-indulgences. The easiest fix is to change your dishware. Research led by Brian Wansink at Cornell University has shown that using small plates and bowls results in less food eaten, and you feel as content as you do when you eat from bigger bowls and plates.

Using red plates and bowls can be an especially good tactic. Red can act as a “stop” cue to our brains, and not just in traffic. Several studies have shown that people eat less from red containers than when food is served on something blue or white.

Another good idea for your holiday feast is to have soft and slow music playing while you eat. We tend to eat to the beat, and loud, fast music encourages us to eat more and faster.

Scents — one area of my research — can also be used as antidotes to overly appetizing aromas. If the smell of frying bacon is making you crazy for a giant breakfast, sniff something entirely different. It’s been shown that a scent that elicits a pleasant past memory can distract you from your cravings, andnon-food aromas or aromas that remind you of your better dieting intentions, like the smell of fruits and vegetables, can help pull you away from temptation.

To relish the delights of the season without paying too high a price, mind your stress levels and pay attention to all the seductive food lures the holidays bring. Keep away from TV. Don’t pepper the house with trays of treats. And when you meet your old college friends for some holiday cheer, go for a brisk walk first. It will burn calories and strengthen willpower during a season of excess consumption.

Rachel Herz is a neuroscientist specializing in perception and emotion. Her latest book is “Why You Eat What You Eat: The Science Behind Our Relationship with Food.”

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