A COMPARISON OF DIETARY TRENDS AMONG RACIAL AND SOCIOECONOMIC GROUPS IN THE UNITED-STATES

Background There may be dietary differences among racial and socioecon omic groups in the United States. Methods Using data from a representa tive sample of adults, we compared dietary trends among blacks and whi tes of varying socioeconomic status. We developed comparable measures of diet and of the consumption of macronutrients and food groups for 6 061 participants in the 1965 Nationwide Food Consumption Surveys, 16,4 25 in the 1977-1978 Nationwide Food Consumption Surveys, and 9920 in t he 1989-1991 Continuing Survey of Food Intake by Individuals (all cond ucted by the U.S. Department of Agriculture). The primary outcome was the score (range, 0 to 16) on the Diet Quality Index, a composite of e ight food-and-nutrient-based recommendations from the National Academy of Sciences. A score of 4 or less was considered to indicate a relati vely more healthful diet, and a value of 10 or more a relatively less healthful diet. Results Overall dietary quality improved in all groups , from a mean Diet Quality Index score of 7.4 in 1965 to 6.4 in 1989-1 991. in 1965, blacks of low socioeconomic status and, to a lesser exte nt, whites of low socioeconomic status had better diets than whites of high socioeconomic status. By the 1989-1991 survey, the differences a mong racial and socioeconomic groups had narrowed. In 1965, 9.3 percen t of whites of low socioeconomic status, 16.4 percent of blacks of low socioeconomic status, and 4.7 percent of whites of high socioeconomic status had mean scores of 4 or less. In the 1989-1991 survey, the res pective percentages were 19.9, 23.5, and 20.0. Fat consumption decreas ed in all groups. The consumption of fruits and vegetables varied litt le over time, except for an increase among blacks of medium and high s ocioeconomic status. The consumption of grains and legumes increased o ver time among whites of medium and high socioeconomic status and decl ined among blacks of low socioeconomic status. Conclusions In 1965, th ere were large differences among groups in dietary quality, with white s of high socioeconomic status eating the least healthful diet, as mea sured by the index, and blacks of low socioeconomic status the most he althful. By the 1989-1991 survey, the diets of all groups had improved and were relatively similar. (C) 1996, Massachusetts Medical Society.