Anatomy of a Holiday Pig-Out

The good news is that it takes 3,500 excess calories to gain a pound — so you might escape from your holiday feast with little to show for it.

The bad news is that at least 40 percent of the excess calories you've eaten probably come from fat. Fat is the most calorically dense (nine calories a gram versus four for protein and carbohydrates), and it converts most easily into fat on your hips.

Your stomach and intestines burn off about 20 percent of the calories in the process of converting excess carbohydrates and proteins into fat. However, your body doesn't burn a single calorie when it is converting nutritional fat into body fat. Your small intestine simply dumps it straight into your bloodstream.

"If you eat 100 excess fat calories, most of the 100 are stored as fat," explains Franca Alphin, R.D., L.D.N., administrative director of Duke University Diet & Fitness Center. With 100 calories of excess carbs, about 20 go to fat storage.

WHAT'S IN YOUR THANKSGIVING FEAST?

Mixed nuts and crackers, 289 calories, 23 g fat

Sour cream and spinach dip, 108 calories, 9 g fat

Small salad with dressing, 173 calories, 16 g fat

Dark and white turkey meat, 239 calories, 10 g fat

Herb stuffing, 292 calories,10 g fat

Cranberry sauce, 200 calories, 0 g fat

Gravy, 84 calories, 7 g fat

Sweet potato casserole, 309 calories, 9 g fat

Green beans almondine, 124 calories, 8 g fat

Cornbread with butter, 338 calories, 23 g fat

Two glasses white wine, 201 calories, 0 g fat

Pumpkin pie with whipped cream, 321 calories, 24 g fat

Pecan pie with whipped cream, 568 calories, 43 g fat

TOTAL: 3,246 calories, 182 g fat (50 percent of total calories come from fat).

Prepare for the Big Feast

You can minimize the damage with a little forward planning:

• Eat light, low-fat, high-fiber meals beforehand, and don't skip whole meals in advance. "You'll be so famished, you'll eat way too much when it comes to the feast," says Anne Dubner, R.D., of the American Dietetic Association. When you're hungry, your body compensates by lowering your metabolism to guard against starvation. "It acts like a dry sponge — and will just soak up more fat."

• Drink less alcohol beforehand. Alcohol douses your resolve, ignites hunger, and adds to your calorie load.

• A half hour before the meal, fill up on water and calorie-free beverages, such as sugar-free soda, iced tea, or coffee. Eat a small snack high in hunger-satisfying fiber, perhaps an apple, carrot, small salad, or yogurt topped with bran. Or have some soup. A study conducted by Baylor College of Medicine in Houston found that people who consumed a bowl of hot soup before meals ate less, lost more weight (about a pound more yearly), and kept it off longer. "It's hot, so you have to eat it slowly and pay attention," says John Foreyt, Ph.D., director of the Nutrition Research Center at Baylor. "Soup also fills your stomach, so you eat less later."

• Increase your workout days in advance. Take a hike, play Frisbee, or go jogging. You may be too tired to gorge, and you may burn off enough calories to compensate for those you'll be bulking up on later. "Physical activity is the currency with which you pay for food," says Pamela Peeke, M.D., author of Fight Fat After 40 (Penguin USA, May 2001).

Read on for tips on how to survive (and enjoy!) the holidays without gaining a pound.