Role of Chia Seed (Salvia hispanica L.) Supplements in Managing Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis

Abstract

Background: Chia seeds have been used traditionally for treating several diseases, including diabetes mellitus (DM). No meta-analysis has holistically analyzed and summarized the effect of chia seed supplementation on glycemic and metabolic parameters in patients with type 2 DM (T2DM); we conducted this meta-analysis to bridge this knowledge gap. Methods: Electronic databases were searched for clinical trials involving patients with T2DM receiving chia seeds in the intervention arm and control diet in the comparator arm. The primary outcome was the changes in glycated hemoglobin (HbA1c) from the baseline at the end of the trial. Results: From 60 initially screened articles, data from four randomized controlled trials involving 244 subjects were analyzed. Chia seed was not superior to control diets in HbA1c reduction (mean differences [MD] −0.09%, 95% confidence interval [CI] [−0.48, 0.29], P = 0.63, I 2 = 95%). It was inferior to control diets in fasting plasma glucose reduction (MD 0.27 mmol/L, 95% CI [0.17, 0.37], P < 0.00001, I 2 = 0%). Chia seed was superior to the control diets regarding reductions in body weight (MD −1.58 mmol/L, 95% CI [−2.96,−0.20], P = 0.03, I 2 = 0%), systolic blood pressure (MD 13.15 mmHg, 95% CI [−22.18, −4.12], P = 0.004, I 2 = 0%) and diastolic blood pressure (MD −7.38 mmHg, 95% CI [−13.04, −1.72], P = 0.01, I 2 = 0%). Changes in C-reactive protein and lipid parameters were similar in the two groups. Conclusion: Current data do not support chia seeds’ glucose-lowering efficacy in patients with T2DM.