Sodium Chloride (NaCl)

 Sodium Chloride (NaCl) is also known as salt in chemical term, is made up of sodium (Na+) and chloride (Cl– ) ions [1]. It appears as crystalline cubes, soluble in water and give a salty taste. Salt most commonly used in food industry for food seasoning or natural preservative [2]. While in medical industry, NaCl is used as for fluid loss treatment and NaCl balance, helping the patients that are incapable to take nutrients and fluids by mouth [3]. Nutritionally, NaCl are essential to regulate the amount of water in human body [4] and maintain the condition of blood pressure especially to individual who are in their middle-aged to elderly with a family history of hypertension [5]. Even though the intake of NaCl is important, its level in the body should wisely be regulated. It is advised to aware with average daily consumption which not too little or too much because it can be harmful to human health. The World Health Organization (WHO) had standardize the recommendation dietary salt intake is around 5g per day [6] and those have risk of heart disease are better to consume less than 2 grams of sodium per day [7]. Excessive level can cause hypernatremia, but lack of NaCl can cause hyponatremia [8, 9]. Extremes hyponatremia can lead to muscle twitches and seizures. While hypernatremia involves in dehydration due to not drinking enough fluids, diarrhea, diuretics and kidney dysfunction [10].

Drugs, diet and toxicity

Sodium chloride solutions are normally used when the patient is diagnosed with sodium depletion and dehy-dration. Treatment is mostly administered intravenously, but in chronic conditions (mild to moderate sodium loss) sodium chloride or sodium bicarbonate can be given orally. Oral rehydration therapies usually use a mixture of alkali metal-based salts such as NaCl, KCl and their citrates (Figure 2.16) .

The most common dietary source of NaCl is table salt, which is used for seasoning and pickling (the high NaCl content inhibits the bacterial and fungal growth as a result of the osmotic gradient). The daily recommended NaCl intake varies depending on the country and the age group. Within the United Kingdom, the maximum salt intake is recommended to be limited to 6 g of NaCl for an adult, whereas intake for children should be significantly lower . Most people exceed this amount on a daily basis, and the high salt plasma levels (hypernatraemia) can result in cardiovascular disorders such as hypertension. 

Low sodium plasma levels (hyponatraemia), which again can be a result of dysfunction kidneys or sodium loss in the bowels, also cause damage to the human body via osmotic imbalances and if necessary have to be treated. Low blood pressure, dehydration and muscle cramps are signs of a sodium deficiency.

Hyponatremia can be the result of illnesses and medications. Some causes that may be related to kidney disease include:

• Kidney failure - the kidneys cannot get rid of extra fluid from the body
• Congestive heart failure - excess fluid builds up in the body
• Diuretics (water pills) - makes the body get rid of more sodium in the urine
• Antidepressants and pain medication - may cause more sweating or urinating than normal
• Severe vomiting or diarrhea - the body loses a lot of fluid and sodium
• Excessive thirst (primary polydipsia) - causes too much fluid intake