Role of food prepared away from home in the American diet, 1977-78 versus 1994-96: changes and consequences

To examine changes, between 1977-78 and 1994-96, in the quantity and quality of food Americans consumed that was prepared at home versus away from home.

Data were obtained from nationwide surveys of food consumption conducted by the US Department of Agriculture (USDA) in 1977-78 and 1994-96. To maximize comparability, we used "day 1" dietary data, which both surveys collected via 24-hour recall.

Individuals 2 years of age and over were selected. USDA sampling weights were used to generate nationally representative estimates.

We categorized foods by preparation at home or at restaurants, fast-food establishments, schools/day care, and other non-home locations. We assessed percent calories from total fat and saturated fat, and the cholesterol, sodium, fiber, calcium, and iron densities of foods prepared at home versus those prepared away from home.

T tests were calculated using accepted procedures to adjust for survey design effects.

Between 1977-78 and 1994-96, consumption of food prepared away from home increased from 18% to 32% of total calories. Meals and snacks based on food prepared away from home contained more calories per eating occasion, and "away" food was higher in total fat and saturated fat on a per-calorie basis than at-home food. "Away" food contained less dietary fiber, calcium, and iron on a per-calorie basis. Among adults but not children, food prepared away from home was more sodium and cholesterol dense.

When developing intervention messages and strategies, nutrition educators need to be aware of the increasing role of "away" food in Americans' diets.