A follow-up study was conducted by the Illinois Division of the American Cancer Society (ACS) in conjunction with the ongoing National Cancer Prevention Study II (CPSII) to determine whether self-report dietary changes are occurring in accordance with the ACS nutrition guidelines and to identify demographic subgroups that may be targeted for future prevention and education programs. A total of 42,300 CPSII respondents completed a 1986 questionnaire and were matched to 1982 baseline data. Dietary items were recorded as "on the average, how many days per week do you eat the following foods?" Individuals with known chronic conditions, body mass index outside a moderate range, and fewer than four completed food items were excluded. The remaining study population (n = 18,062) included men and women who were apparently healthy and primarily over the age of 50. The distribution of foods reported in 1982 and changes in foods consumed (1982-1986) among selected food groups varied modestly by sex, age, and educational level. Modest changes in the direction of decreasing intake of high-fat foods and increasing intake of high-fiber foods and cruciferous vegetables were reported. Dietary changes consistent with the ACS nutrition guidelines appear to have taken place in this population, particularly for the use of fried foods in males and intake of high-fiber foods and cruciferous vegetables in females.