African-American (AA) individuals are disproportionately affected by cardiovascular diseases. Plant-based diets (PBD) may be cardioprotective in part through their high antioxidant capacity and low inflammatory load. We tested the hypothesis that AA individuals adhering to a 100% PBD would have better vascular health than AA individuals following a typical American diet (TAD). Eighteen AA individuals participated; 9 (24 ± 4 years; 6 females) were following a PBD for 2.4 ± 0.8 years and 9 (21 ± 2 years; 5 females) were following a TAD. Blood lipids and C-reactive protein (CRP) were assessed. Peripheral and central blood pressure (BP) were measured, and vascular function tests included cerebrovascular reactivity to hypercapnia, brachial artery flow-mediated dilation and reactive hyperemia, and local heating-induced cutaneous hyperemia. Total (TC) and low-density lipoprotein (LDL-C) serum cholesterol was lower (TC: 142 ± 30 vs. 174 ± 36 mg/dL; LDL-C: 76 ± 17 vs. 106 ± 33 mg/dL; p < 0.05 and d > 0.80 for both) and serum CRP tended to be lower (0.38 ± 0.18 mg/L vs. 0.96 ± 0.89 mg/L; p = 0.05, d = 0.91) in the PBD cohort. Brachial (b) and central (c) mean arterial BP (MAP) were lower in the PBD cohort (bMAP: 86 ± 5 vs. 91 ± 7 mm Hg; cMAP: 81 ± 5 vs. 87 ± 7 mm Hg; p < 0.05 and d > 0.80 for both). All indices of vascular function were similar between groups (p > 0.05 for all). A PBD was associated with more optimal blood lipid concentrations and decreased peripheral and central BP in AA individuals, but this association was not present in the various indices of vascular function. Registered at ClinicalTrials.gov: NCT05344287.
Keywords: Black Americans; Noirs américains; disparité de santé; endothelial function; fonction endothéliale; health disparity; hypertension; inflammation; régime végétalien; vegan diet.