The glycocalyx serves as the interface between flowing blood and endothelial cells, the single cell layer that lines blood vessels, and is crucial for normal blood vessel function. Specifically, the glycocalyx protects endothelial cells from oxidative stress and inflammation and enables blood vessel dilation, which is largely dependent on the bioavailability of the vasodilatory molecule nitric oxide. Importantly, glycocalyx thickness decreases with age and is predictive of major adverse cardiovascular events in older adults free of cardiovascular disease. Therefore, interventions aimed at restoring glycocalyx thickness in older adults are desperately needed. Endocalyx Pro is a commercially available glycocalyx precursor supplement, manufactured by Microvascular Health Solutions, designed to 1) repair a damaged glycocalyx, 2) protect against damage to the glycocalyx, and 3) synthesize new glycocalyx components, and has been used to increase glycocalyx thickness in humans. However, no study has tested if glycocalyx thickness restores glycocalyx thickness in older adults and improves blood vessel function. Thus, the purpose of this investigation is to determine if 12-weeks of Endocalyx Pro supplementation alters glycocalyx thickness and blood vessel function in older adults. The investigators will use a camera placed under the tongue to determine glycocalyx thickness. The investigators will measure blood vessel function by measuring brachial artery dilation with ultrasound and arterial stiffness using pressure probes placed on the carotid and femoral artery.