Sodium chloride (salt) is essential to the body. The sodium in salt helps transmit nerve impulses and contract muscle fibers. Working with potassium, it balances fluid levels in in the body. But you only need a tiny amount of salt to do this, less than one-tenth of a teaspoon. The average person gets nearly 20 times that much.
The body can generally rid itself of excess sodium. In some people, though, consuming extra sodium makes the body hold onto water. This increases the amount of fluid flowing through blood vessels, which can increase blood pressure.
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