Effects of chronic consumption of specific fruit (berries, citrus and cherries) on CVD risk factors: a systematic review and meta-analysis of randomized controlled trials.
Purpose: This review aims to compare the magnitude of the effects of chronic consumption of fruits; specifically berries, citrus and cherries on cardiovascular disease (CVD) risk factors. Methods: PubMed, Web of Science, Scopus, and psycARTICLES were searched from inception until January 2020. Forty-five chronic ( 1 week) randomised controlled trials assessing CVD risk factors including endothelial (dys)function, blood pressure (BP), blood lipids and inflammatory biomarkers were included. Results: Investigated interventions reported improvements in endothelial function (n = 8), inflammatory biomarkers and lipid status (n = 14), and BP (n = 10). Berries including juice of barberry, cranberry, grape, pomegranate, powder of blueberry, grape, raspberry and freeze-dried strawberry significantly reduced SBP by 3.68 mmHg (95% CI - 6.79 to - 0.58; P= 0.02) and DBP by 1.52 mmHg (95% CI - 2.87 to - 0.18, P = 0.04). In subgroup analysis, these associations were limited to cranberry juice (SBP by 1.52 mmHg [95% CI - 2.97 to - 0.07); P = 0.05], DBP by 1.78 mmHg [95% CI - 3.43 to - 0.12, P = 0.04] and cherry juice (SBP by 3.11 mmHg [95% CI - 4.06 to - 2.15; P = 0.02]). Berries also significantly elevated sVCAM-1 levels by 14.57 ng/mL (85% CI 4.22 to 24.93; P = 0.02). Conclusion: These findings suggest that supplementing cranberry or cherry juice might contribute to an improvement in blood pressure. No other significant improvements were observed for other specified fruits. More research is warranted comparing different classes of fruit and exploring the importance of fruit processing on their cardiovascular-protective effects.