Among them, five reported the efficacy of berberine on TNF-α, and the results found that berberine reduced the level of TNF-α in patients with T2DM to some extent (SMD = −1.44, 95% CI (−2.72, −0.16), P = 0.03, I2 = 97%, 95% CI (0.95, 0.98)) (Figure 9). Here, TNF is linked to type 2 diabetes mellitus.