Cerebral blood flow (CBF) is the rate of perfusion of brain tissue, typically 50-60 mL per 100g per minute. Brain consumes 20% of cardiac output despite being 2% of body mass.
Mechanism — Autoregulated tightly via local vasodilation. Endothelial dysfunction, atherosclerosis, and microvascular disease reduce CBF. Lower CBF correlates with cognitive decline and dementia risk.
Use case — Improve via Zone 2 cardio (most leveraged), vascular health (BP, lipids), nitric oxide support, ginkgo or vinpocetine where appropriate, and hyperbaric oxygen in select cases.
Caveats — CBF testing is research-grade (arterial spin labeling MRI, PET). Clinical surrogates: cognitive testing, history of hypertension, vascular risk factors.