One of the numerous functions of everyday life for your body is maintaining the internal balance or homeostasis of the body. Your body has several mechanisms for controlling its internal environment -- from temperature control to energy production to urine production. You can detect some changes that occur in the body's coping mechanisms through urine production. Your kidneys play a vital role in water and electrolyte concentrations. When you consume salt, you affect how the body functions.
Salt and Fluid Retention
Your body tightly controls the concentration of electrolytes like sodium. Electrolytes are chemicals that carry an electrochemical charge when dissolved in solution. So vital is this system to life that your body uses up to 40 percent of your resting energy expenditure toward maintaining it. When you consume salt, you throw off this balance, forcing the body to compensate for the change in electrolyte concentrations. To keep it at the same percentage of concentration, your body will retain water. This action will, in turn, impact urine production.
The control of salt and water in your body involves a complex series of reactions called the renin-angiotensin system. Several organs participate in this system, with the primary organ being the kidneys. When the fluid concentration in the body changes, this causes the hypothalamus to stimulate the pituitary gland to release a hormone called anti-diuretic hormone (ADH). Your body retains water through reabsorption in the kidneys, resulting in less urine production.
You will notice the effects of excessive salt consumption through a change in the color of your urine. The darker yellow color shows that it has become more concentrated with less water excreted. You will also notice that you may need to urinate less frequently. The hypothalamus will also detect the higher concentration of salt in your body and stimulate thirst. This occurs because maintenance of the proper concentrations of electrolytes and water in the body is vital for healthy body functioning.
These effects on urine production reflect how the body is coping with changes in its internal environment. They also carry health risks. When your body retains water, it initiates a mechanism that will lead to an increase in blood volume. The more blood your cardiovascular system has to move, the harder it must work. This will lead to an increase in blood pressure and risk of blood vessel damage. Changes in urine production are one way to detect if your body is getting too much salt. It is a signal that you may need to curb your salt intake to lessen the workload on your cardiovascular system.
- Linus Pauling Institute; Sodium; Victoria J. Drake; November 2008
- "Principles of Anatomy and Physiology"; G. Tortora et al; 2005
- National Library of Medicine: Renin-Angiotensin System
- Centers for Disease Control and Prevention; Americans Consume Too Much Sodium (Salt); February 24, 2011
- Centers for Disease Control and Prevention: Sodium -- The Facts