The traditional Thanksgiving dinner, in which the eaters are better stuffed than the eat-ee, resonates with psychic meanings beyond giving thanks, anthropologists say.
When we eat more than we need to eat for Thanksgiving dinner, we're making powerful statements about who we are, who we're not and what we used to be.
Everybody, in all tribes and all nations, celebrates by eating, says Sidney Mintz, an anthropology professor at the Johns Hopkins University.
"Eating is the single most important activity in which we engage," he says. "It's our most powerful drive, more powerful than sex. If you don't want to eat, you're sick. If you stop altogether, you're dead.
"Eating becomes attached to the notion of holidays, which are special days, and what we eat is bound up with two parts of our sense of history."
First, we remember child-hood. "Eating at holidays re-awakens our attachment to the people who used to feed us," he says.
Second, our dinner defines our association with our tribe or nation or people.
"It expresses a sense of identity," Dr. Mintz says. "You are a part of something when you celebrate. It's like saying, 'We are one people because of what we eat; they are not us because they don't eat it.' The foods of the holidays are the foods of distinctivity. They're flags we raise to say, 'This is who we are.' "
So while we could dine just as well on a Dover sole, or boeuf bourguignon, or chicken cacciatore, chances are we won't. On Thanksgiving, we're all descendants of the Pilgrims and Indians; the food we want is distinctively American.
And for some of us, the historic re-enactment echoes from wells deeper than that, Dr. Mintz says. In homes where one of the men carves the turkey while the women pass the vegetables, we're also playing out the tribal roles of male hunters, female gatherers.
Our habitual holiday overindulgence is reminiscent of our origins, too. In tribes in which food normally is scarce, celebratory meals are always eaten in excess, he says. It's another way to mark the difference between this dinner and all other dinners.
Actually, overeating might hark back to something even more basic than tribal behavior.
Like hibernating animals, we're light-sensitive creatures. We don't crawl into caves and sleep through the winter, but some of us suffer from seasonal affective disorder (SAD), a wintertime depression accompanied by lethargy, sluggishness -- and a craving for quick-energy food such as carbohydrates, says Dr. David Neubauer, director of the acute psychiatric unit at Francis Scott Key Medical Center.
Even people who don't have SAD may have similar food cravings in fall and winter, Dr. Neubauer speculates. "It may be that the Thanksgiving and Christmas feasts are synchronized with this process."
Sweet potatoes, stuffing, dinner rolls, pumpkin pie -- the foods we're most likely to have in multiple helpings -- are all high in carbs.
Our other national holiday -- the Fourth of July -- calls for a different kind of dinner, Dr. Neubauer points out. It's a picnic that finishes with summer fruits. We don't generally ask for a lot of extra sandwich rolls and potato salad in the summertime.
Even the dietarily prudent will generally eat more on Thanksgiving, and some of them may well recognize that they're "pigging-out," says Tony Whitehead, Ph.D., chairman of anthropology at the University of Maryland College Park.
But the Thanksgiving symbols -- national, religious, familial, historic -- may just be too strong for everyday control, he says.
Even in this country, where we've really turned people around regarding food and health, when it comes to this holiday, it's sacrilegious to say you're not going to eat this kind of food," Dr. Whitehead says.
Whatever motives lie deep in the unconscious brain, however, the traditional dinner imposes some modern problems. Today's housewife may well be working eight hours a day away from home. Cooking the traditional holiday feast is going to be a strain.
But given a choice, many women will opt not to eat out on Thanksgiving, and many will insist on doing all the food preparation themselves rather than buying it pre-cooked.
"A woman who views [home-cooked meals and desserts] as central to her femininity in the modern world faces a difficult trial," says Dr. Mintz. "We want to continue to infuse our personal lives with the activities that give them a personal quality, and buying prepared food contributes to depersonalization."
The home cook may not even want to take advantage oconvenience foods or diet-type methods. Traditional foods are generally prepared the traditional way, Dr. Whitehead says.
"If you ask people why they cook that way, they'll say 'Because people prefer foods made in the old fashioned way. I fix it that way because people love the way I do it,'" he says. "And then everyone compliments their home cooking, and that's a further incentive."
It's no wonder, then, that a lot of dieters will wake up with a hefty hangover of guilt Friday.
*Blessed be the picky eater
If abstemiousness on Thursday is impossible, there are a few little adjustments, short of self-denial, that can keep the calories out of the Alpine range.
* Take the skin off the turkey, advises Richard Waranch, Ph.D., assistant professor of psychology and medical psychiatry at the Johns Hopkins School of Medicine.
* Eat one helping, not piles and piles of food.
* Eat breakfast and lunch: "The research shows some relationship between not eating all day, and over-eating at dinner," he says. "If you skip lunch, the tendency is to make up for it later."
* And try, generally, to do what thin people do, he advises: "If you look at the thin people at the table, you'll see that they don't really eat a lot more than they usually do. They don't gorge themselves just because it's there."