Soy and Brain Vascular Function

Cognitive performance is negatively related to an impaired glucose metabolism, possibly due to impairments in brain vascular function. Supported by the statement from the American Heart and American Stroke Association that healthy plant-based diets, which consist of soy foods, protect against cognitive decline, we now hypothesize that soy-induced changes in glucose metabolism cause beneficial effects on brain vascular function thereby improving cognitive performance. The primary objective of this intervention study is thus to evaluate in elderly men and women the effect of a 16-week soy intervention on cerebral blood flow, as quantified by the non-invasive gold standard magnetic resonance imaging (MRI) perfusion method Arterial Spin Labeling (ASL). Cerebral blood flow is a robust and sensitive physiological marker of brain vascular function. Secondary objectives are to examine effects on glucose metabolism using the oral glucose tolerance test and cognitive performance as assessed with a neurophysiological test battery.