There are a lot of psychological reasons we pack it on during the run from Thanksgiving until the first of the year, and we can't just blame it all on the rich food and decadent desserts.
Added stress is one reason and then there's the theory that it's a natural instinct to binge before the diet season begins at the first of the year. "We call that the Last Supper Syndrome," says Dr. Melinda Sothern, LSU Health Sciences Center Professor of Public Health and Director of Behavioral and Community Health Sciences.
Lack of sleep also contributes, as folks are trying to buy gifts, plan parties, decorate and still maintain their regular schedule.
How much do we gain? "At least clinically, what we've observed is between five and eight pounds," says Dr. Sothern and the amount gained usually depends on how much we weighed to start.
And then there's the fact that locals just don't know correct serving sizes any more. For example Dr. Sothern says, "That large spoon you use to serve stuffing, and you put that on your plate and it takes a fifth or a fourth of your plate, that's actually four servings."
But she says the stress can be particularly devastating not just to our waistlines, but to our overall health. "When you're stressed you produce inflammatory agents that are associated with making the fat cells travel to where they're not supposed to such as the liver, and the pancreas and the heart even. Stress causes the worst kind of weight gain. It causes the kind of weight gain that ends up in your abdomen, and then causes all kind of problems with insulin, promoting higher risks of diabetes."
Of course the doctor says, exercise is the first to go when things get really hectic around the holidays, but she says there are ways to add it in. She suggests dancing at holiday parties or "There's actually some pretty good research around some of the interactive video gaming devices as well...Wii Fit, Wii Sport, Dance Dance Revolution, Guitar Hero."