A standardized test of cardiovascular health knowledge was administered to 1367 students, ages 12-18 years, and 562 adults, ages 20-60 years. Mean scores were: ages 12-14 years, 42.5 +/- 0.7% (SEM); 15-18 years, 49.1 +/- 0.1%; 20-40 years, 68.7 +/- 0.7%; 40-60 years, 68.2 +/- 0.7% correct. Cardiovascular health knowledge increased linearly in the student population, averaging 3.08% per year. Increases continued to occur in adults, but plateaued after age 40 years, despite an increasing incidence of cardiovascular disease in this age group. Health knowledge was highly correlated with the highest educational achievement. At all age levels, knowledge of diagnostic tests was highest and knowledge of pathophysiology lowest. A personal or family history of heart disease or history of an elevated serum cholesterol was not a stimulus for increases in health knowledge.