Overindulging at a holiday party is a given. But don't feel too guilty about all the cookies and beer you put down. "One night won't make much of a difference, and if it does push your weight up by a pound, we wouldn't know if that could just be fluid retention or related to whether or not we've used the bathroom (sorry to be graphic, but it's true)," says dietitian Rebecca Blake, senior director of clinical nutrition at Mount Sinai Beth Israel.
That's because as with exercise, it takes repetition and consistency to make lasting changes in your body, so occasional indulgence shouldn't derail efforts to maintain your weight. Before you get too excited, note that Blake considers "occasional" binging once or twice a year, not once or twice a week or month.
Still, "there's no standard dietary guideline for how much overeating leads to weight gain because it depends on the individual," says Wesley Delbridge, a dietitian and spokesman for the Academy of Nutrition and Dietetics. How often you can get away with overindulgence depends on your age, genetics, how fast your metabolism is, how frequently you exercise and the medications you might be taking, he says.
Your Body on a Plate of Cookies
The physiological effects of consuming too much food are pretty immediate: The pancreas goes into overtime and works extra hard to process all the sugar, says Delbridge. Because your glucose (simple sugar) levels have skyrocketed, your body doesn't know what to do with it all. So the easiest thing for it to do is to store it as fat.
Depending on the person, it takes 10 to 20 minutes for the leptin hormone to tell your brain it's full. "That's why you feel awful and in pain – because you ate for 20 minutes longer than you should have," Delbridge says.
As gross as that sounds, resist the urge to make up for the binge by severely restricting your food intake the next day, because it won't help.
Problems with the Post-Holiday Fast
"Where a lot of people go wrong after they overeat, because they feel guilty, is to go to the extreme with a fast or cleanse, which is bad," Delbridge says. "The body likes homeostasis and doesn't like extremes, and when you do a detox or cleanse – which haven't been scientifically proved to be beneficial at all — the body goes into starvation mode. Your hormones get even more confused and your metabolism slows down."
Then when you do eat normally again, or indulge, because you've been so "good," your body will cling to those calories even more, making it even more difficult to shed any pounds. And it doesn't take long for this starvation mode to kick in: "Anything longer than 24 hours and your body starts to freak out," he adds.
After a night of guilt-enducing consumption, Blake recommends a light breakfast and a day of normal healthy eating and moderate exercise, just like every other day.
Both dietitians say that although you can't really "erase" overeating, look at it as a nudge to stop obsessing, accept it and move on rather than a cue to feel helpless or defeated.
What You Can Do Before a Party
The best way to deal with holiday calorie temptations is to plan and wait, Delbridge says. Eat a small high-fiber snack, such as an apple, before a party so you don't arrive starving. And you should "save" some calories up in anticipation by eating a lighter lunch than usual, for example, suggests Blake.
Also important: Because fullness signals can take a while to register, wait 20 minutes after a meal and see how you feel before going for seconds.
And because alcohol lowers inhibitions, try to be mindful about how much you're drinking. Don't let hosts "top you off" so you lose track of how much you're drinking, and switch between alcoholic drinks and club soda.
"I think it's important to remember that restaurant or holiday meals and parties are not an excuse to overeat," Blake says. "Our lifestyles include so many of these situations that we do need to learn how to handle them in a healthy way, and we should try to avoid the 'compensatory' mentality and learn to work these events into our everyday calorie budget."
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