Despite the health risks of too much salt, the body cannot function without sodium. Sodium serves numerous life functions from the cellular level to nervous system control. Sodium is a mineral that occurs naturally in the environment. Both humans and animals require it. However, proper balance is essential in order to realize its benefits and avoid the health risks associated with over-consumption.
Sodium is vital for proper body function even at the most basic level. Sodium along with chloride and potassium are responsible for maintaining the electrochemical gradient between the environment within the cells and the fluid around it called the membrane potential. Nervous system impulses and muscle contractions are controlled by the electrochemical activity that sodium makes possible, meaning that nervous impulses are controlled by electrical charges within these chemicals. A deficiency in sodium can lead to a serious health condition called hyponatremia. Symptoms include headache and nausea. Left untreated, hyponatremia can cause seizures and coma.
Sodium plays an essential role in maintaining blood volume. The concentration of dissolved particles in plasma controls blood volume. The body maintains specific concentrations in the blood and the surrounding tissues. When you eat salty foods, your body retains water to dilute the concentration of sodium in your bloodstream. Sodium is one of several chemicals responsible for the maintenance of this system.
The chemistry of the body involves many complicated reactions. The relationship between sodium and calcium is no exception. If your diet is high in sodium, you risk calcium loss from your bones due to the chemistry between sodium and calcium. Like sodium, calcium is essential for life. The body will break down bone to free up calcium. Over time, this action might increase your risk of developing osteoporosis. Too much sodium also puts you at risk of other diseases, such as gastric cancer and heart disease.
While sodium is crucial, excessive intake can lead to serious health consequences. A diet high in sodium will increase blood volume to the point where it can affect blood pressure. Simply, the more fluids your body retains, the higher the blood volume. With more blood, the heart must work harder to pump blood, increasing the pressure within blood vessels. The Centers for Disease Control and Prevention estimate that Americans consume more than twice the recommended 1,500 mg of sodium per day. Processed foods and restaurant food account for over three-quarters of salt intake in the average American diet.
- "Human Physiology: From Cells to Systems"; L. Sherwood; 2008
- Linus Pauling Institute: Sodium (Chloride)
- American Association of Kidney Patients: Why Does Salt Cause High Blood Pressure?
- Journal of the American College of Nutrition: Role of Dietary Sodium in Osteoporosis
- Centers for Disease Control and Prevention: Most Americans Should Consume Less Sodium
- Centers for Disease Control and Prevention: Americans Consume Too Much Sodium (Salt)