Your Thanksgiving Dinner By the Numbers Totals 3,690 Calories

If you ever wondered why it felt so good to unbutton your pants after the family's big Thanksgiving dinner, here's your answer.

The average American can consume up to 3,690 calories on Thanksgiving.

About 20% of the calories are consumed before we even sit down to eat, thanks to all of the snacking and picking at foods as they're being prepared.

Macaroni and cheese had one of the biggest calorie counts with 200 per serving and stuffing has 180 calories per serving.

But the biggest diet killers are dessert with pecan pie coming in at 450 calories per slice and cheesecake at 330 calories per slice.

Surprisingly, the dish with the most calories per serving was not mashed potatoes or macaroni and cheese, as some family members guessed, but sweet potatoes. Macaroni and cheese came in a distant second.

Take a look at this item by item chart of your Thanksgiving meal calorie count courtesy of the Cornell University Food and Brand Lab.