Ginkgolides are a group of diterpene lactones found in the leaves of the Ginkgo biloba tree. They are often referenced as active constituents in standardized Ginkgo biloba extracts. The primary mechanism by which Ginkgolides, particularly Ginkgolide B, are believed to support capillary and microvascular health is through their antagonism of platelet-activating factor (PAF), which can help reduce platelet aggregation and improve microcirculation. This effect can, in theory, support capillary integrity and function.

Scientific studies have investigated Ginkgo biloba extract (which contains Ginkgolides) for its effects on peripheral circulation and vascular health. Some clinical trials have shown that Ginkgo biloba may improve symptoms of peripheral vascular disease (such as intermittent claudication) and may have modest benefits for cerebral blood flow, especially in elderly populations. However, most research uses the whole standardized extract (EGb 761), making it difficult to attribute effects specifically to Ginkgolides as opposed to other components like flavonoids.

Meta-analyses and systematic reviews generally conclude that while there is some evidence for improved microcirculation and reduced capillary fragility, the overall quality of evidence is moderate and not uniformly strong. As a result, the scientific support for Ginkgolides in capillary health is present but not definitive, meriting a moderate evidence rating.