Can dieting around the holidays backfire?

Dr. Jennifer Ashton appears live on "GMA" to talk about how intense dieting before or after big holiday meals may actually cause you to over-indulge.
2:25 | 11/27/17

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Transcript for Can dieting around the holidays backfire?
holiday season which means lots of great food that could make dieting difficult. Starting early can actually backfire and Dr. Jen Ashton is here and, Jen, before we start I have a quick question. How many of you by a show of hands are now dieting today after indulging over this past Thanksgiving? I'm already seeing -- yeah. Oh, wow. That's about right. So people say, Jen, can you tie to watch what you eat before a holiday party. It sounds like a good plan but it can actually turn against you? It can and I'll explain why. A very complicated process. Dieting. It's not as simple as calories in, calories out. Take a look. What happens in general when people start to diet. Their weight may drop a little. That produces an increase in the hunger hormones. People are hungrier and metabolism actually slows down so that your body can restore itself to its equilibrium which is its heaviest weight, the set point theory so starting around holiday time not the best time to tart an aggressive diet. Then you have to -- if you put fewer calories in your body regulates then you add more calories because you indulge because you have this at the table. You have a three-bite rule. Listen, I want to be clear. Everyone needs to find -- you want some of this at the end? What works for them and this is by no means scientific rigor but a three-bite rule if you go to a party you will see tempting things like this, take three bites and move on. Talking about three bites of a delicious cheesecake that's almost half the slice. That's a huge slice, by the way or you could share it with someone then you'll hear other tips like eat before you go so you're not ravenous. I think also, you know, I practice something that I find working really well which is if you just keep talking a lot you're not going to be able to eat a lot in sparkling water in your hand I think that helps too. You can't put food in your other hand if you're holding a glass so it's about finding a trick, having a plan in advance that will work for you. There's no right or wrong. How about a plan afterwards. Best way to burn it off. You have to be active. Everyone has a phone with an app. Track your step, walk to and from the party. A great time of year to start something new like a group cardio class can be fun with friends then when you get back to work the next day please use the stairs. Every little bit helps. Great advice. Thank you very much, Jen.

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