Supersized appetites

The study was based on an analysis of previous surveys of US eating habits. It found that between 1971 and 2000, American men increased calorie intake from 2,450 to 2,618 a day on average. The increase among women was from 1,542 to 1,877 calories a day.

Carbohydrates in men's diets increased from 42.4 percent in 1980 to 49 percent in 2000. For women the increase was 45.4 percent to 51.6 percent. The percentage of fat went down significantly.

Based on these figures, it would seem that the advice outlined in the US Agriculture Department's Food Guide Pyramid has changed Americans' eating habits, though not in the way it was intended. The Agriculture Department hoped that if people ate more whole grains and other carbohydrates, they would reduce their consumption of fats.

While the percentage of fat has declined, the actual consumption of fats has gone up slightly. The increase in carbohydrates is just much higher. Barry M. Popkin, professor of nutrition at the University of North Carolina, cautioned this week that the studies may not give an accurate portrayal of fat consumption. They are based on surveys that ask how much a person has eaten over the last 24 hours. Popkin said that people often underestimate the amount of fat they consume. The CDC believes reports that as of 2002, 64 percent of US adults were overweight.

The latest survey by the CDC provides powerful ammunition against the contention of some people in the food industry that lack of exercise is to blame for weight problems. The National Soft Drink Association, responding to the epidemic of obesity among young people, financed a study that concluded that calorie consumption among adolescents rose only 1 percent between 1980 and 2000 while physical activity fell 13 percent.

The soft drink study has yet to be published, so it is impossible to reconcile its findings with those of the CDC, and exercise ought to be an important element in any weight control program. Popkin has found that portion sizes among adults and youngsters have soared, along with restaurant usage and increases in package dimensions by food manufacturers. It is hard to believe that teenagers are exempt from this supersizing trend. The Agriculture Department is in the midst of revising the Food Guide Pyramid, a contentious matter as food companies lobby to make sure their products are not criticized. The department needs to include a reminder of a reality the CDC study has confirmed: In order to keep their weight down, many Americans need to eat less.CORRECTION - An editorial yesterday understated the number of homeless adults in Massachusetts in a 1999 estimate. The number is at least 33,000.