Ecological Trends of Food Availability Yield Clues To Americans

Harnack and colleagues from the University of Minnesota analyzed the quantities and types of foods and nutrients marketed in America over the past three decades, and found that the per capita availability of energy increased 15% between 1970 and 1994. The availability of fish and chicken, fresh and frozen fruits and vegetables, and low fat milk. Higher-fat cheeses showed a 325% increse. Also expanding were common ingredients of processed foods such as corn sweetener, flours and cereals, shortening and cooking oils. These increases could be attributed to the growth of fast food restaurants and other away-from-home eating establishments, where much of the food is prepared by deep fat frying.

Trends in purchasing and preparation of food have markedly changed in ways that likely contribute to overweight. Americans are eating more meals outside the home, relying more on convenience foods, and may be consuming larger food portions. Of every dollar used to buy food, American households spent 20% to eat away from home in the 1970s, but by 1992 this proportion had increased to 38%. Fast food restaurants are currently growing at a rate of 7% annually. Supermarkets increasingly offer convenience foods and pre-made dinners in order to compete with the restaurant industry. Larger portion sizes, according to the authors, might also be contributing to the weight gain problem, though more research is needed. Restaurant menus collected and analyzed by the National Restaurant Association between 1988 and 1993 showed a 12% increase in offerings of more than one portion size, such as a "king size" steak.

SOURCE/REFERENCE: American Journal of Clinical Nutrition, May 30, 2000