Which mineral is key to maintaining fluid and acid-base balance in the body?

Sodium plays a crucial role in maintaining fluid balance and acid-base homeostasis in the body. As an essential electrolyte, sodium helps regulate blood pressure and blood volume, which are vital for proper physiological functions. It does this by attracting water, which can influence the overall hydration status of cells and tissues. Sodium is also involved in nerve transmission and muscle function.

While calcium and potassium are important for various bodily functions, including muscle contraction and blood coagulation, they are not primarily responsible for fluid and acid-base balance to the same extent as sodium. Iron, on the other hand, is crucial for oxygen transport and energy metabolism but does not directly influence fluid balance. Thus, sodium is the key mineral involved in maintaining the balance of fluids and the acid-base environment in the body.