The effects of grape seed extract supplementation on cardiovascular risk factors, liver enzymes and hepatic steatosis in patients with non-alcoholic fatty liver disease: a randomised, double-blind, placebo-controlled study

Randomized, double-blind, placebo-controlled parallel study in overweight or obese adults with ultrasound-confirmed moderate to severe non-alcoholic fatty liver disease (NAFLD). The grape seed extract arm included 25 participants, with 25 participants in the placebo arm; the study was conducted in Ahvaz, Iran.

Oral grape seed extract (GSE) 520 mg/day was given as two 260 mg tablets taken with the morning and evening snacks for 2 months. The active GSE arm was compared with placebo.

Grape seed extract showed an overall favorable effect versus placebo after 2 months, improving lipid profile, blood pressure, liver enzymes, and ultrasound-determined hepatic steatosis. Post-intervention LDL-c was 101.89 ± 22.88 mg/dl with GSE versus 125.82 ± 30.15 mg/dl with placebo (P = 0.003), total cholesterol was 182.58 ± 21.59 versus 204.18 ± 33.67 mg/dl (P = 0.01), HDL-c was 48.91 ± 7.32 versus 42.93 ± 7.33 mg/dl (P = 0.006), LDL/HDL ratio was 2.13 ± 0.58 versus 3.02 ± 0.87 (P < 0.001), and AIP was 0.50 ± 0.14 versus 0.61 ± 0.12 (P = 0.008). SBP, DBP, and MAP were also lower with GSE at 118.00 ± 9.12, 84.40 ± 8.20, and 95.60 ± 7.37 mm Hg versus 130.40 ± 14.85, 97.40 ± 10.71, and 108.40 ± 11.06 mm Hg, respectively, all with P < 0.001; ALT and AST were lower at 24.28 ± 8.61 and 18.75 ± 4.08 versus 35.06 ± 8.70 and 22.28 ± 6.84 (P < 0.001 and P = 0.03). TG was not significantly different post-intervention (158.84 ± 34.26 vs 177.12 ± 38.70 mg/dl; P = 0.08).

The trial was small, single-center, and short in duration, with only 25 participants in the active arm and 2 months of follow-up. These features limit precision, long-term inference, and generalizability, and the excerpt does not provide full detail for all metabolic endpoints such as insulin resistance measures.