In the short term, the effects of caffeine are well studied both as a vasodilator and vasoconstrictor, but given that chronic use produces specific adaptations, is the long term effect of caffeine use reduced or increased blood flow to connective tissue?
With regard to underlying biological mechanisms, most research has been devoted to BP-raising effects of caffeine. However, there are many other substances in coffee, such as polyphenols, soluble fibre and potassium, which could exert a beneficial effect in the cardiovascular system. Although the precise nature of the relation between coffee and BP is still unclear,
most evidence suggests that regular intake of caffeinated coffee does not increase the risk of hypertension.
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