Calorie labeling: whom can you trust?

Many products marketed as "health" or "diet" foods provide calorie information on their labels. But the reliability of a packaged food's calorie count tends to vary with how widely that product is distributed, according to a new study by Steven B. Heymsfield and his co-workers at the Obesity Research Center of Saint Luke's-Roosevelt Hospital Center in New York City.

The researchers purchased 40 different prepared foods, quantified their calorie content, and compared those values to information on the product's label. In the Sep. 22-29 JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION, they report that although nationally advertised foods provide accurate calorie counts, regional brands tend to contain an average of 25 percent more calories than labeled. "Buyer beware" was their caution when it comes to local brands: These products averaged 85 percent more calories than stated on their labels.

In the Dec. 31, 1992 NEW ENGLAND JOURNAL OF MEDICINE, Heymsfield's team reported data indicating that some patients fail to lose weight, though claiming to eat low-calorie diets, because of a "substantial misreporting" of calories eaten. The researchers now suspect that some of that failure is due to "people honestly believing that they eat fewer [calories] than they do because they have been misinformed by food labels." Unless the government steps up policing, the team concludes, food labeling laws may not benefit obese consumers.