Portion sizes larger today than 20 years ago

NEW YORK (Reuters Health) - Portion sizes young adults serve themselves have swelled significantly over the past 20 years, a new study shows.

Portion sizes of ready-to-serve foods and restaurant servings have grown over the past two decades, Jaime Schwartz of Portable Nutrition in New York City and Dr. Caron Byrd-Bredbenner of Rutgers University in New Brunswick, New Jersey note in their report.

Many believe this has helped to contribute to the current obesity epidemic.

To investigate whether there's been a similar increase in the amount of food people will serve themselves, the researchers observed a group of 177 young adults serving themselves breakfast, lunch or dinner. The researchers modeled their study on similar research published in 1984.

The researchers "unobtrusively" estimated portion sizes by weighing serving dishes before and after the study participants had served themselves.

The participants chose significantly larger portions of cornflakes, milk on cereal, orange juice, and fruit salad than their counterparts in 1984, the researchers found. However, chosen portions of sugar and salad dressing declined.

The findings suggest that the growth in portion sizes offered at grocery stores and restaurants has influenced how people view the appropriate amount of food to eat per serving, the researchers write in the Journal of the American Dietetic Association.

For example, people can now buy "single-serving" containers of 2.2 cups of orange juice, a size that wasn't available 20 years ago. A typical portion size of orange juice based on current food labeling standards is eight ounces, or half a cup.

"To 'undistort' typical portion sizes, policymakers should refine Nutrition Facts labels to make the number of servings in a single container more prominent and to fund a consumer awareness campaign to highlight the parallel relationship between increasing portion size and body weight," the researchers conclude.

"Bringing 'portion distortion' under control could help confront and combat the growing diet-related problems in this country," they conclude.

SOURCE: Journal of the American Dietetic Association, September 2006.