American Journal of Clinical Nutrition, Vol 16, 374-379, Copyright © 1965 by The American Society for Clinical Nutrition, Inc.

An Examination of Calorie Availability and Consumption in the United States, 1909-1963

¹ From the Graduate School of Nutrition, Cornell University, Ithaca, New York

In this discussion it has been shown that the food disappearance statistics, often mislabeled food consumption, are not precise scientific measurements. They are rough approximations of the amount of food taken from the retail market. No attempt is made to adjust for kitchen or plate waste and some of the factors used to convert from wholesale to retail weights are outmoded. It was shown that when the age structure of the population changes, the use of per capita measures tends to cover up the impact of these changes; also that a sizable discrepancy exists, on the order of 1,300 to 1,400 calories, between daily calorie disappearance and estimated needs per standard calorie consumption unit. Until more is known about the nutrient make-up of this discrepancy, it is not possible to describe accurately the actual nutrient consumption.

To make the disappearance statistics more accurate and useful, two lines of attack seem necessary. The conversion factors used to determine retail weight equivalents should be re-evaluated and brought up to date. This is particularly necessary for meat and other major items in the diet. The rise of the supermarket and chain-type retail operation have introduced many changes in food marketing practices and these should be reflected in the conversion factors.

In addition, a series of conversion factors that would allow one to convert from retail weight equivalents to some measure of normal consumption would be extremely useful. Some studies are now being made in this area that include the entire household. It might be more feasible to approach this problem on a commodity-by-commodity basis. For example, through laboratory and "in-the-home" observation, determine how much of the fat and other nutrients in a canned ham are normally ingested. If the effort was concentrated first on those individual food items where we are certain there is substantial wastage, we would soon be in a position to make more precise statements on actual food consumption for the population as a whole.

In the meantime, researchers who use the USDA food consumption statistics should realize that these are imprecise measures and should be treated accordingly.