The effect of ginger (Zingiber officinale) on glycemic markers in patients with type 2 diabetes.

Background: Ginger (Zingiber officinale) is one of the functional foods which contains biological compounds including gingerol, shogaol, paradol and zingerone. Ginger has been proposed to have anti-cancer, anti-thrombotic, anti-inflammatory, anti-arthritic, hypolipidemic and analgesic properties. Here, we report the effect of ginger supplementation on glycemic indices in Iranian patients with type 2 diabetes.

Methods: A double-blind, placebo-controlled, randomized clinical trial was conducted on 20-60 -year-old patients with type 2 diabetes who did not receive insulin. Participants in the intervention and control groups were received 3 g of powdered ginger or placebo (lactose) (in capsules) daily for 3 months. Glycemic indices, total antioxidant capacity (TAC), malondialdehyde (MDA), C-reactive protein (CRP), serum paraoxonase, dietary intake and physical activity were measured at the beginning and end of the study, and after 12 h fasting.

Results: Comparison of the indices after 3 months showed that the differences between the ginger and placebo groups were statistically significant as follows: serum glucose (-19.41 ± 18.83 vs. 1.63 ± 4.28 mg/dL, p < 0.001), HbA1c percentage (-0.77 ± 0.88 vs. 0.02 ± 0.16%, p < 0.001), insulin (-1.46 ± 1.7 vs. 0.09 ± 0.34 μIU/mL, p < 0.001), insulin resistance (-16.38 ± 19.2 vs. 0.68 ± 2.7, p < 0.001), high-sensitive CRP (-2.78 ± 4.07 vs. 0.2 ± 0.77 mg/L, p < 0.001), paraoxonase-1 (PON-1) (22.04 ± 24.53 vs. 1.71 ± 2.72 U/L, p < 0.006), TAC (0.78 ± 0.71 vs. -0.04 ± 0.29 µIU/mL, p < 0.01) and MDA (-0.85 ± 1.08 vs. 0.06 ± 0.08 µmol/L, p < 0.001) were significantly different.

Conclusions: This report shows that the 3 months supplementation of ginger improved glycemic indices, TAC and PON-1 activity in patients with type 2 diabetes.