Safety Profile
Overall safety rating: Generally Safe
Grape Seed Extract Side Effects & Safety
This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer
Potential Side Effects
- Mild GI discomfort (nausea, stomach upset)
- Headache (usually transient)
- Dizziness at higher doses
- Allergic reaction in grape-sensitive individuals (rare)
Drug & Supplement Interactions
- Anticoagulants/antiplatelets — OPCs may have mild antiplatelet effects; use with caution
- Antihypertensive drugs — additive blood pressure lowering; monitor BP
- Iron supplements — tannins in GSE may reduce iron absorption; take separately
Maximum Dose
Do not exceed: 600mg/day (well-tolerated in clinical trials)
References
- Zhang H, Liu S, Li L, Liu S, Liu S, Mi J, Tian G (2016). The impact of grape seed extract treatment on blood pressure changes: A meta-analysis of 16 randomized controlled trials. Medicine. DOI PubMed
- Feringa HH, Laskey DA, Dickson JE, Coleman CI (2011). The effect of grape seed extract on cardiovascular risk markers: a meta-analysis of randomized controlled trials. Journal of the American Dietetic Association. DOI PubMed