Portion Distortion

More than half the adults in the U.S. today are dangerously overweight. Our kids are getting fatter, too. Why are so many over-eating? CBS This Morning Consumer Correspondent Herb Weisbaum has one possible explanation.

Health experts say the food industry is dishing out portions that are so big it's almost impossible not to eat more calories than is wise.

Restaurants are giving customers what they want: more for their money. From a nutritionist's point of view, that's a real problem.

Nutritionist Carrie Latt Wiatt says, "As far as portion size goes, we are out of control."

In her latest book, Portion Savvy, Wiatt blames the food industry for making it way too easy to eat too much. Wiatt explains, "They know we want more, therefore they give us more, but they're helping to make us fat because we've lost sight of what a portion really is."

Are these bigger portions leading to bigger people? Absolutely. Think about it. If a plate is put in front of you, the psychology behind it says you will eat it because you paid for it.

To prove the point, we set up a little experiment at a movie theater in the Chicago area. It was a real-life test, using varying sizes of popcorn.

University of Illinois researcher Brian Wansink and some of his students from the university's Food and Brand Lab ran the study for us. They gave free popcorn to everyone who came to see an afternoon showing of a movie.

For the test, they used two different bucket sizes - big and really big. Both buckets had so much popcorn few people could eat all of it. Our researchers knew just how much was inside each one, because they'd weighed them. The buckets were given out randomly, and none of the moviegoers were told why they were getting free popcorn.

After the show, they gathered up all popcorn containers and re-weighed them. Guess what? The people who got the larger containers ate significantly more than those with the smaller buckets. In fact, they ate 50 percent more. For popcorn, that translates into about 120 extra calories.

Why does bigger portion size equate to more consumption? "Because if you have it, you'll eat it," says Lindner.

To find out just how far out of whack today's serving sizes are, researchers at Tufts University in Boston analyzed a number of common foods, like bagels, muffins and pasta. They compared what they bought to what the government guidelines say is a serving size.

The results were eye opening. "It was everywhere we went, everything was super-sized, says Lawrence Lindner, editor of Tufts University Health & Nutrition Letter.

For example, government guidelines define a muffin as weighing to ounces and having about 200 calories. But the muffins Lindner found for sale generally weighed about 7 ounces and had about 700 calories.

A serving of pasta should be a half cup after cooking, just 100 calories. Most restaurants serve portions containing two and a half cups. The restaurant portion is actually 5 servings of pasta, packing 500 calories. And that's before they pour on the sauce.

The Tufts researchers knew that bagels have gotten bigger. But Lindner says they were surprised to learn just how big. We found that bagels weigh 4 or 5 ounces," he says. "So that when you're having a bagel, you're really having 4 to 5 slices of bread at one sitting."

Here's the bottom line: If you're trying to watch your weight, buy small and eat small. You'll take in fewer calories, and that's the key to dropping those extra pounds.

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