Across 4 studies, 3 reported beneficial effects of red grape-derived interventions (primarily grape seed extract) on reducing aspartate aminotransferase (AST) levels, with effect sizes ranging from small to moderate. Effects were observed in clinical populations with NAFLD and β-thalassemia at doses of 100 mg/day and 520 mg/day over 4–8 weeks. The evidence is moderate, with 3 statistically significant findings, but the small number of studies and narrow populations limit generalizability.
Caveats: Evidence base is small (only 4 studies) — conclusions should be considered preliminary. Most studies were conducted in specific clinical populations (NAFLD, β-thalassemia), so generalizability to healthy individuals is uncertain. The single neutral study evaluated quercetin and curcumin rather than grape seed extract, suggesting form-specific effects may vary. Doses and durations were inconsistent, with only two studies reporting dose information (100–520 mg/day) and two reporting duration (28–60 days).
The study aimed to investigate the iron-chelating, antioxidant, anti-inflammatory, and hepatoprotective activities of grape seed extract (GSE) supplement as well as its safety in β-thalassemia major (β-TM) pediatric patients receiving deferasirox as a standard iron-chelation therapy.
from: Grape seed extract in combination with deferasirox ameliorates iron overload, oxidative stFlavonoids intervention significantly decreased aspartate aminotransferase (AST)
GSE supplement significantly attenuated the serum levels of ... AST (p = 0.000)
insulin, HOMA-IR, TC, TG, LDL-c, ALT, AST, AST/ALT, SBP, DBP and MAP decreased and QUICKi and HDL-c increased significantly (p-value for all < 0.05)
In contrast, quercetin and curcumin supplementation did not show a statistically significant difference compared to control groups in these outcomes.