The kidneys are the organs in the body which keep up with the excess sodium in the bloodstream. As sodium accumulates in the body it draws water in to dilute the sodium. In this process both the amount of fluid surrounding cells and the volume of blood in the bloodstream increases. Increased blood volume creates more pressure on blood vessels and heart. Over time, the extra work and pressure can stiffen blood vessels, leading to high blood pressure, heart attack, and stroke. It can also lead to heart failure.
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