This study measured dietary compliance and attitudes of 68 hypercholesterolemic men and women who were randomly assigned to one of the following diet regimens: (1) low fat, low cholesterol diet; (2) low fat, low cholesterol diet + 50 g/day oat bran; (3) 50 g/day oat bran supplemented diet; and (4) 42.5 g/day processed oat bran supplemented diet (ready-to-eat cereal with an increased β-glucan content). Attitudinal and compliance scores were the most positive for those on the processed oat bran, followed by those on fat-modified regimens, while subjects on the unprocessed bran scored their diet regimen the most negatively. Dietary compliance decreased significantly over the 12-week study period for the fat-modified groups, compared with the adherence to the bran-supplemented regimens for which compliance did not appreciably decline. The fat-modified lifestyle, however, was reported as much more likely to diffuse throughout the family than the use of oat supplements, despite encouragement and provision of additional bran earmarked for this purpose. These findings support past research that the addition of a food to the diet is met with less resistance than food restriction, if the added food is familiar, convenient and palatable. © 1991, Society for Nutrition Education and Behavior. All rights reserved.