Grape Seed Extract for Capillary Density

Typical dose

Recommended dose

150-300 mg daily standardized to OPCs

Expected timeframe

6-12 weeks for vascular function measures

Protocol

form

Extract standardised to 95% oligomeric proanthocyanidins (OPCs); products vary widely and unstandardised preparations are not comparable

duration

6-12 weeks

co factor

Take with food in divided doses. Evidence is mixed, and the endpoint is the problem. Grape seed proanthocyanidins have demonstrable vascular effects in humans - trials show improved flow-mediated dilation, modest blood pressure reduction and reduced capillary fragility, and there is a long European tradition of using OPCs for capillary permeability in chronic venous insufficiency. But capillary density is a distinct anatomical measure requiring capillaroscopy or biopsy, and it has essentially not been studied after grape seed extract in humans. Improved endothelial function and reduced capillary leak are not the same as growing new capillaries; angiogenesis in humans is driven by exercise training, which reliably increases capillary density in trained muscle.

titration

Increase to 300 mg/day after two weeks if tolerated. Doses up to 300 mg/day are typical in trials; some vascular studies used up to 600 mg/day short-term

starting dose

150 mg/day of standardised extract with food

What the studies say

Less likely to help if