Studies show that as people eat out more often, their calorie consumption goes up. This is probably due not just to what we order, but also how much. New research shows that restaurant portion sizes have grown markedly, with amounts two to five or more times larger than the "standard" serving size.

According to government studies, adult calorie consumption increased about 200 calories a day from the late 1970s to the mid-1990s. Although this increase may be due to many changes in our eating patterns, a study in the Journal of the American Dietetic Association shows that more frequent eating out or ordering take-out is linked with higher daily calorie and fat consumption.

Portion sizes in fast food, take-out and family-type restaurants were studied by researchers at New York University (NYU) and reported in a recent American Journal of Public Health. Many of the restaurant portions were substantially larger than the standard serving sizes used in government nutrition recommendations like the Food Guide Pyramid. The average bagel was double the standard serving, steak was more than double, a muffin was three times larger, pasta was equal to almost five standard servings, and cookies were an astonishing seven times the standard serving size.

Portions larger than a standard serving are not always a problem. For example, one way to reach the health goal of five to ten servings of fruits and vegetables is to include in your meal a portion equal to two (or even three) servings. Unfortunately, portion sizes of fruits and vegetables in restaurants were not noted in the NYU report. But experience tells us these foods are often served in restaurant meals as garnish - or not even included.

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Grain products like bread, rice and pasta would not be at all inappropriate in a one-cup portion (equal to two standard servings). But when a portion of pasta is almost five standard servings, or when meat is twice the recommended serving size and eating one cookie is really like eating seven, the problem with frequent restaurant eating becomes obvious. When calorie consumption increases, the nutritional proportion of healthy foods is probably toppled.

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It wasn't always this way. Researchers in the NYU study also looked at how portions at these restaurants have changed over the years. Today's French fry, burger and soda portions are about two to five times the portions originally served. The number of large-sized portions has increased more than ten-fold in the last 30 years.

This trend is a U.S. phenomenon. A "large" portion in Europe is smaller than a "large" in America. In this country, the food industry promotes larger portions as bargains that give you more for your money. But while larger servings may cost less per ounce, eating more than you really need is not a good deal.

When a range of portions is offered, the "small" size of virtually everything is usually the best choice - except for vegetables. Remember that even a "medium" was once a "large" not too long ago. Observe portion sizes, using comparisons like a deck of cards as a standard meat portion, and an average adult's fist as a maximum grain portion.

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The key is to eat portions based on true hunger cues rather than eating until the plate is empty. Unfortunately, this is hardest to do when eating "on the run," the very time that much of our fast food and take-out eating is done.