Abstract
Background: Epidemiological evidence shows that fruit and vegetable (FV) intake reduces cardiovascular risk. Comparative effects of diets with different FV types on cardiometabolic disease risk markers remain unclear.
Objectives: This study aimed to compare the effects of standardised diets differing in FV types on vascular function, other cardiometabolic disease risk markers, urinary and plasma biomarkers in free-living adults with untreated prehypertension.
Methods: In a 9-wk randomised, controlled, crossover trial at 2 centres, 39 adults consumed standardised, provided diets with either 8 daily portions of common FV (apple, banana, pear, bell pepper, carrot, tomato), 8 daily portions of citrus and cruciferous FV, or 2 daily portions (low FV diet, control) for 2 wk per arm, with a 1-wk washout. Adherence was assessed using 24-h urinary potassium, sodium, and targeted plasma carotenoids and metabolites. The primary outcome was office blood pressure; secondary outcomes included pulse wave velocity (pwv), augmentation index standardised at 75 beats per minute (AIX75), lipids, and C-reactive protein (CRP). Between-group differences were assessed using linear mixed models with diet and period as fixed effects, and participant as random effect.
Results: Thirty-six participants completed the study (67% male, mean age 54±6 y; systolic BP 131.7±9.0 mmHg, total cholesterol: 5.4±1.1 mmol/L). No between-group differences were observed in office BP, PWV, AIX75, or CRP. Both common and citrus fruits and cruciferous FV diets tended to increase 24-h urinary potassium (by 6.94 mmol/24-h, P≤0.1; 8.0 mmol/24-h, P≤0.06, respectively), while 24-h urinary sodium remained comparable across diets (P≥0.87). Common FV diet significantly increased α- and β-carotene, and lycopene (P≤6.3x10-4), whereas citrus fruits and cruciferous FV increased lutein/zeaxanthin, β-cryptoxanthin, proline betaine, N-methylproline, and S-methyl-L-cysteine sulfoxide (P≤6.9x10-8). Common FV diet reduced total (-0.19 mmol/L, 95% confidence interval (CI): -0.32,-0.05), LDL (-0.15 mmol/L, 95% CI: -0.26,-0.03), and HDL (-0.05 mmol/L, 95% CI: -0.09,-0.00) cholesterol, whereas citrus and cruciferous FV reduced urinary creatinine (-1.19 mmol/24-h, 95% CI: -2.27,-0.11). No effects were observed on weight and physical activity.
Conclusions: Objective biomarkers confirmed FV adherence and suggest that FV types differentially modulate lipid and metabolic responses within 2 wk, without measurable vascular effects.