Trends in individual consumption of dietary fat in the United States, 1920-1984.

Coronary heart disease mortality has declined in the United States since 1968. Because diet has been implicated, a search was conducted of published individual assessments of food intake since 1920. One hundred seventy-one studies, ranging from 8 to 20,000 subjects and covering all ages, all ethnic groups, and both sexes, were analyzed by regression, with values weighted by number of subjects in each study. Results show fat intakes rising from approximately 34% energy in the 1930s to 40-42% in the late 1950s to mid 1960s then falling steadily to approximately 36% energy in 1984. This trend was seen for all age and sex groups. Saturated and monounsaturated fatty acid intakes fell from 18-20% energy in the early 1950s to 12-13% energy in 1984 whereas polyunsaturated fatty acid intakes rose from 2-4% energy to 7.5%. These results differ markedly from food supply trends and indicate a fall in US fat intake, which preceded the decline in heart disease mortality.