When eaten in conjunction with other blood pressure-lowering nuts like walnuts, almonds are one of the most powerful cardiovascular superfoods available. 2) Cayenne pepper. Arguably one of the fastest foods to lower blood pressure, cayenne pepper is a powerful vasodilator, which means it helps expand blood vessels and improve blood flow. This effect naturally lowers blood pressure levels by increasing the rate at which blood flows throughout the circulatory system, which in turn takes some of the pressure off arterial walls.