Fig. 13

Meta-regression analysis showing the association of HgA1C concentration (WMD), and mean age, supplementation duration, BMI and baseline FBS. Decrement in HgA1C was associated with younger (β = 0.10 CI 0.01, 0.19: p-value = 0.032) and longer duration (β = − 0.05 CI − 0.08, − 0.02: p-value = 0.003) of treatment, lower BMI (β = 0.27 CI 0.00, 0.54: p-value = 0.049) and lower baseline FBS (β = 0.13 CI 0.005, 0.262: p-value = 0.044)