The effect of sumac on cardiovascular risk factors in adults: A systematic review and meta-analysis of randomized controlled trials

Clinical evidence suggests the beneficial effects of sumac on cardiovascular risk factors. However, these results are controversial. This systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to determine the effect of sumac supplementation on cardiovascular risk factors in adults. The PubMed, Embase, Web of Science, and Cochrane databases were searched from inception to 30 December 2023 to identify RCTs that were published in English. Data were presented as weighted mean difference (WMD) and associated 95 % confidence interval (CI). The quality of the included trials was measured using the Cochrane Collaboration's modified risk of bias tool. A pooled analysis of 16 trials showed that sumac consumption led to a significant reduction in fasting blood glucose (WMD: -6.03 mg/dl; 95 % CI: -9.67 to -2.39), hemoglobin A1c (WMD: -0.45 %; 95 % CI: -0.59 to -0.31), triglycerides (WMD: -9.07 mg/dL; 95 % CI: -16.19 to -1.94), low-density lipoprotein cholesterol (WMD: -5.58 mg/dL; 95 % CI: -11.27 to -0.12), BMI (WMD: -0.22 kg/m²; 95 % CI: -0.38 to -0.05), weight (WMD: -0.85 kg; 95 % CI: -1.44 to -0.27), waist circumference (WMD: -0.54 cm; 95 % CI: -0.92 to -0.15), and diastolic blood pressure (WMD: -2.72 mmHg; 95 % CI: -4.16 to -1.29). High-density lipoprotein-cholesterol level also increased significantly (WMD: 3.69 mg/dL; 95 % CI: 1.81-5.57). The overall results support possible protective and therapeutic effects of sumac on cardiovascular risk factors in adults. Additional prospective studies are suggested using longer intervention periods and higher supplementation doses to confirm these results.