The Effect of Berry-Based Food Interventions on Markers of Cardiovascular and Metabolic Health: A Systematic Review of Randomized Controlled Trials

Scope: Epidemiological evidence, animal, and in vitro studies suggest that berry consumption may ameliorate markers of cardiovascular disease (CVD). The aim of this systematic review is to evaluate findings from berry-based randomized controlled trials (RCTs) to establish the effects of berry consumption on markers of cardiovascular and metabolic health. Methods and results: PubMed and Web of Science are searched for RCTs investigating berry consumption on CVD risk outcomes in adults. A total of 23 studies (which includes 1168 participants) out of 1384 records meet the inclusion criteria. Of these 23 studies, 17 RCTs are of high quality, where 12 RCTs (71%) report beneficial effects of berry consumption on CVD risk markers. Overall, 4/11 RCTs that observe a reduction in systolic and/or diastolic blood pressure (BP); 3/7 RCTs report favorable effects on endothelial function, 2/3 RCTs report improvements in arterial stiffness, 7/17 studies observe benefits in blood lipids, and 3/6 studies report improvements in glycemic profile. Conclusion: Our evaluation of the literature indicates that more than two-thirds of high-quality trials have reported beneficial effects of berry consumption on markers of CVD risk. This systematic review contributes moderate to strong evidence for the inclusion of berries as part of a cardioprotective diet.