000730 Food Trends Play Role in Obesity Epidemic

New York - Increased availability of convenience foods, changes in food preparation, and eating out more often are factors that appear to be contributing to the obesity epidemic among Americans, say researchers.

In an effort to examine “ecological trends” in food intake, Dr. Lisa J. Harnack and colleagues from the University of Minnesota in Minneapolis used agriculture, business, and medical library databases to determine the quantities and types of foods and nutrients available in the United States between 1970 and 1998.

Their data supports a 15.2% increase in per capita per day availability of food energy between 1970 and 1994, according to their report in the June issue of the American Journal of Clinical Nutrition.

The report also describes increasing expenditures on food eaten away from home. In the 1970s, Americans spent 20% of every food dollar on eating out, but by 1992, this figure had grown to 38%, and the trend “shows no sign of weakening,” Harnack's team report. They note that while the restaurant industry is growing at a “modest rate of 3% annually,” fast-food restaurants are growing at a rate of 7% annually. There is now an average of 1 fast-food hamburger restaurant per 10,000 US residents, the team reports.

And even when Americans cook, they are spending less time on food preparation--the proportion of meals that include at least one item made from scratch fell from 43% in 1987 to 38% in 1997.

“Along with offering convenience foods such as frozen dinners, supermarkets are offering precooked meals...to better compete with restaurants,” the study authors note.

On the favorable side of the nutrition ledger, the authors report an increase in the availability of lower-fat meats, poultry, fish, and shellfish and a decrease in the availability of higher-fat meats.

Increases were also seen in the availability of low-fat nonfat milk, most fruits, all vegetables, and all types of flour and cereal products, the investigators note, as well as in both high-energy- containing and low-energy-containing sweeteners.

The researchers write that their review of fat consumption shows “a complicated picture.”

“Americans appear to be selecting lower-fat foods over higher-fat alternatives...however, some of the data suggests that total fat intake has increased,” they write. Overall per capita availability of fats and oils increased by nearly 22%, however, reflecting the increasing trend of fat and oil use in fast-food and other restaurants. But “the ecologic data suggest that intakes of saturated fat have declined while intakes of monosaturated and polyunsaturated fats have increased.”

“The upward shift in energy intake suggested by the ecologic data reviewed is consistent with trends in overweight,” the investigators propose, “which suggest that ecologic data may more closely reflect actual changes in energy intake than do national dietary survey data collected at the individual level.”

RETURN TO HOME PAGE

E-mail: sflanagan@sprintmail.com