Which hormone regulates sodium and potassium levels in the body?

Aldosterone is the hormone that primarily regulates sodium and potassium levels in the body. It is produced by the adrenal glands, specifically in the adrenal cortex. The function of aldosterone involves promoting the reabsorption of sodium ions from the kidney tubules back into the bloodstream while facilitating the excretion of potassium ions into the urine. This regulation is vital for maintaining electrolyte balance, fluid balances, and blood pressure homeostasis.

By increasing sodium reabsorption, aldosterone indirectly assists in water retention, which can increase blood volume and blood pressure. Additionally, the careful balance of sodium and potassium is crucial for proper cardiovascular function and overall cellular activity.

In contrast, the other hormones listed, such as thyroxine, cortisol, and insulin, have different primary roles. Thyroxine is mainly involved in regulating metabolism, cortisol plays a significant role in stress response and metabolism regulation, and insulin primarily manages glucose levels in the blood. Therefore, while all these hormones have critical functions, aldosterone is specifically tasked with managing sodium and potassium levels in the body.