We verified that venous blood T1 quantified in vivo in humans using fast and non-invasive MRI can be used to derive hematocrit (Hct) values reliably. This Hct information can be used for a more individual estimation of oxygen extraction fraction (OEF) from venous blood T2 measurements. Furthermore, inverse correlation between Hct and baseline cerebral blood flow (CBF) was observed across subjects. Measurement of Hct, OEF and CBF allowed determination of oxygen delivery (OD~CBF∙Hct) and consumption (cerebral metabolic rate of oxygen, CMRO2~CBF∙Hct∙OEF). When compared to CBF, OD and CMRO2 showed less inter-subject variations among normal volunteers.