Have Americans started Supersizing Thanksgiving, too?

What happens when you combine Thanksgiving -- a holiday dedicated to overindulging -- with America's love of all things Supersized? Not as much as you'd think.

While Americans are notorious for cranking up the calories and portions compared to a generation or so ago, small changes in the nation's diet seem to have buffered Thanksgiving dinner from some -- but not all -- of our bigger-better mentality.

To find out just what has changed about America's official gut-busting dinner, The Associated Press asked Cornell University's Food and Brand Lab to analyze recipes from the 1950s and compare them to contemporary versions.

Previous studies of non-Thanksgiving recipes by lab director Brian Wansink had found that calorie counts for many classic cookbook recipes have ballooned by nearly 40 percent during the past 70 years.

But Thanksgiving staples didn't follow that trend.

Calorie counts for five of the eight recipes tested actually dropped by almost a third when comparing 1956 Better Homes and Gardens recipes to the 2006 edition of the ''Better Homes and Gardens New Cookbook,'' changes Wansink attributed partly to the use of lower-calorie ingredients, such as low-fat milk instead of cream. Surprisingly, some serving sizes went down over the decades, too.

Per-serving calorie counts dropped an average of 102 calories for green beans with almonds, stuffing, mashed potatoes, candied sweet potatoes and pumpkin pie. They went up 26 calories for rolls and were essentially unchanged for corn and candied carrots.

That puts the total calorie count for a contemporary Thanksgiving dinner of those eight fixings, plus a turkey drumstick, at 2,057 calories. The tally for 1956 was 2,539, according to Cornell researcher Laura Smith.

Wansink's research repeatedly has shown that controlling portions is not something Americans today are skilled at.

''There might be a little less butter put in the dressing or there might be fewer marshmallows on the sweet potatoes,'' he said. ''But where you end up messing with them, you end up serving up a lot more than your grandfather served himself.''