Health Effects
The mineral sodium is present in all cells and body fluids and is essential for life. Sodium is required for maintaining various cell and body functions such as the regulation of fluid volume, blood pressure, and acid-base balance. Sodium also plays a role in signal transmission in the nervous system and activates many enzymes.
The World Health Organization (WHO) recommends a daily sodium intake of less than 2,000 mg (approximately 1 teaspoon of salt) for adults. The German Nutrition Society (DGE) recommends a daily intake of about 1,500 mg of sodium, with a maximum intake of 6 g of table salt per day.
An excess of sodium intake may result in an increase in blood sodium, though hypernatremia through diet is hardly possible, as the body constantly self-regulates and maintains a balance. However, a high intake of salt (NaCl) is associated with high blood pressure. Since many foods contain hidden salt, a lot of sodium may be unconsciously consumed. Hypernatremia can develop with insufficient water intake or a high fluid loss. Certain diseases (e.g., heart or liver failure) can also promote the development of hypernatremia. Older individuals, or diabetics with a poorly controlled diet, are at risk. Symptoms of hypernatremia include, among others, thirst, confusion, excitability, seizures, or coma.
Sodium deficiency is very rare. Because an insufficient intake of sodium through food is compensated by hormonal mechanisms, which reduce urinary excretion. However, a deficiency can occur with substantial fluid losses, resulting from severe vomiting, diarrhea, intense sweating, extreme physical exertion, or the intake of certain medications (e.g., diuretics). Signs of sodium deficiency include muscle cramps or low blood pressure. Severe sodium deficiency requires intensive medical treatment.
Diagnosis:
Sodium ions are the most important positively charged electrolytes outside of body cells. The measurement of sodium ions in blood and urine is important for assessing the body's water and electrolyte balance. Measuring sodium in hair or nails does not play a role in assessing the body’s sodium status, according to present knowledge.