Sodium: Sodium is vital to normal body growth. This mineral is important in helping nerves and muscles function properly. It's main purpose it to help "pump" fluids and nutrients in and out of the cells and cell membranes. Too much sodium can contribute to high blood pressure. Your kidneys regulate the amount of sodium kept in your body. When sodium levels are low, your kidneys conserve sodium. When levels are high, they excrete the excess amount in urine.

If your kidneys can't eliminate enough sodium, the sodium starts to accumulate in your blood. Because sodium attracts and holds water, your blood volume increases. Increased blood volume, in turn, makes your heart work harder to move more blood through your blood vessels, increasing pressure in your arteries. Certain diseases such as congestive heart failure, cirrhosis and chronic kidney disease can lead to an inability to regulate sodium.

Some people are more sensitive to the effects of sodium than are others. People who are sodium sensitive retain sodium more easily, leading to excess fluid retention and increased blood pressure. If you're in that group, extra sodium in your diet increases your chance of developing high blood pressure, a condition that can lead to cardiovascular and kidney diseases.