Sodium is a soft, light, extremely malleable silver-white metallic element and comes in many forms. It is naturally abundant in combined forms and is known to most people in the form of common table salt (sodium chloride). But natural sodium is also present in unprocessed foods such as meat, fish, poultry, milk etc. Other forms in which sodium is found are sodium hydroxide, commonly known as caustic soda and sodium carbonate, best known under the name soda ash.
 Functions and Uses
Sodium works with potassium in the human body to maintain the water balance. Small amounts are needed to maintain blood pressure and normal function of muscle contraction and conduction of nerve impulses. It is also important for maintaining normal heart rhythm and acid base balance. Sodium helps the body to retain water and prevent dehydration. The body also uses sodium to regulate blood pressure and blood volume by retaining water.
Sodium is popular as a food preservative and an ingredient in snacks. In some ancient societies, sodium was even used as a form of currency.
 Food Sources
Sodium as a dietary source is present in almost all foods as a natural ingredient. It is found naturally in meats, nuts, grains, fruits, vegetables, and dairy products in low amounts. It is also added to many other foods as an additional flavoring. A main dietary source of sodium is sodium chloride, or common table salt. Other common dietary sources of sodium are processed foods to which salt is added during preparation, such as processed meats, cheeses, salted snacks, pickled food, canned and packaged foods. Salt-based seasonings also contribute to sodium in foods.
Although the exact minimum requirements of sodium are not known, the National Research Council of the National Academy of Sciences recommends 1,200 to 1,500 mg of sodium each day for adults. This recommendation is based on the amount needed to replace the sodium loss and can be met by eating a healthy, nutritionally well-balanced diet.
 Ways to Reduce Sodium Intake
Persons with high blood pressure, congestive heart failure, liver cirrhosis, and kidney disease may need to take much lower amounts of sodium. Some of the ways to reduce sodium intake are as follows:
- Cooking using fresh ingredients than processed foods.
- Substituting fresh fruits and vegetables for salty snack foods.
- Avoiding use of table salt.
- Choosing foods that are low in sodium.
- Using spices and herbs like pepper, fresh lemon, sea salt, ginger and garlic to season food.
Sodium deficiency is rare but it does occur and leads to a condition called hyponatremia. Conditions like burns, diarrhea, certain kidney diseases, intense sweating or other conditions that cause rapid loss of water from the body can lead to sodium deficiency. Drinking only water while engaging in challenging athletic events can also easily lead to hyponatremia. Symptoms include digestive disorders, lethargy, confusion, muscle weakness, memory loss, fatigue, and lack of concentration or appetite, cramping of the muscles and dizziness. It can also make a person faint and suffer palpitations of the heart.
Excessive consumption of sodium on a regular basis is often associated with high blood pressure (hypertension) and oedema in persons who are sensitive to sodium. Increased salt intake leads to an increased retention of fluid and therefore increased volume of blood. The heart needs to work harder to pump this increased blood volume to all the tissues in the body, thus resulting in hypertension. High sodium diets can also cause fluid retention and swelling in the feet and hands.
- What is Sodium?
- Medical Encyclopedia