The vegetarian diet has been associated with lower blood pressure (BP) in elderly white Americans. This study was undertaken to determine whether or not long-term adherence (at least 5 years) to a plant-based diet is similarly related to lower BP in older black Americans, a group exhibiting significant risk for hypertension (HT). Anthropometric characteristics, nutrient intake, and resting systolic and diastolic BP were measured in older black vegetarians (n = 27, age = 69.3 +/- 1.7 years), black nonvegetarians (n = 37, age = 65.4 +/- 1.2 years), white vegetarians (n = 85, age = 66.7 +/- 1.0 years), and white nonvegetarians (n = 54, age = 65.2 +/- 0.9 years). Older black vegetarians were significantly leaner and exhibited lower average systolic BP (131.4/76.8 mm Hg) and less hypertension than the black omnivores (141.6/76.2 mm Hg), but had significantly higher average BP than either dietary group of older white adults (vegetarians: 120.9/66.7 mm Hg; nonvegetarians: 122.8/67.6 mm Hg). These data suggest that long-term adherence to a vegetarian diet by older black Americans may afford some protection against hypertension, but in comparison to older white adults, does not completely offset their apparently greater susceptibility to untoward elevation of BP.