The purpose of this clinical trial is to investigate the potential benefits of tart cherry supplementation on vascular health in healthy older adults. There is growing evidence that flavonoid-rich tart cherries may be cardioprotective due to their beneficial effects including antioxidant properties, improvement in endothelial function, and modulation of immune function and inflammation in cellular and animal studies. However, studies that have examined the effect of dietary consumption of tart cherry in human subjects are limited, and none of the studies have investigated their effects on endothelial function and arterial stiffness. Vascular aging predominantly includes increased arterial stiffness and endothelial dysfunction. Oxidative stress and inflammation are also linked to the aging process. Therefore, this study will investigate the effect of tart cherry supplementation on endothelial function measured by flow-mediated dilatation and arterial stiffness measured by cardio-ankle vascular index as well as biomarkers of endothelial dysfunction, inflammation, vascular injury, oxidation, lipids, nitric oxide status, and flavonoid and phenolic acid profiles in healthy older adults. With the aim of understanding individuals genetic variations that produce different responses to tart cherry supplementation, this study will further explore the association between these responses to tart cherry supplementation and single nucleotide polymorphisms in loci related to the risk of cardiovascular diseases, metabolism and inflammatory processes.