The benefits of diet to the cardiovascular system are widely reported in the literature and evidence is accumulating that individuals who consume high quality diets rich in certain nutrients are protected from cardiovascular disease via a number of mechanisms. With ageing, collagen formation in arteries increases and this in turn results in stiffness of the vasculature with a subsequent decreases in the elastic properties inherently required to provide optimal circulation. The end result is deterioration of the cardiovascular system with its associated symptoms of ill health. Increased collagen may structurally decrease the elasticity of the arteries, however there are other non-structural mechanisms that also increase arterial stiffness. For example vascular tone can be increased by various hormones that affect the contractibility of the endothelium. These mechanisms have the potential to be altered short-term by nutritional intervention and so are of interest to nutritional scientists.
A systematic review of the literature surrounding arterial stiffness and dietary intervention has been carried out by Pase et al (2011). In this review, 75 relevant studies were included based on the criteria of consisting of randomised controlled human clinical trials of common dietary interventions in the treatment of arterial stiffness. The review supported the theory that n-3 fish oils and soy isoflavones were beneficial in the treatment of arterial stiffness. In addition, evidence was present that salt restriction and ingestion of fermented milk products containing bioactive peptides may be beneficial at improving arterial stiffness. Evidence also suggests that caffeine ingestion acutely increases arterial stiffness, which supports other clinical data that suggests vasoactive properties for methylxanthines. These result support the numerous studies that suggest that n-3 fatty acids and soy isoflavones may show beneficial effects on the cardiovascular system, and mechanistically this may partly involve reducing short-term arterial stiffness.