Importance of Mineral Salts and Ions in Human Body

Inorganic substances made of metallic elements such as iron, sodium, potassium, calcium and magnesium, or of non-metallic elements, such as chlorine and phosphorus. The mineral salts are found in two forms viz. solubilized ions (such as sodium and potassium ions in cells) or non-solubilized form such as calcium in our bones.

Cations and Anions

Ions are atoms or molecules that are electrically charged due to losing or gaining electrons {electrons are negatively charged as we all know}.

• The cations are ions with positive charge. A cation is formed when a neutral atom or molecule loses electrons (gains positive charge). Important cations in our body are sodium (Na⁺), potassium (K⁺), calcium (Ca⁺⁺), iron (Fe⁺⁺, Fe⁺⁺⁺), magnesium (Mg⁺⁺), zinc (Zn⁺⁺) and manganese (Mn⁺⁺).
• Anions are ions with negative electrical charge. An anion is formed when a neutral atom or molecule gains electrons (gains negative charge). Important anions in our body are chloride (Cl^–), phosphate (PO₄^—), bicarbonate (HCO₃^–), nitrate NO₃^–) and sulphate (SO₄^–).

Role of mineral salts in osmotic regulation

In our body, mineral salts along with glucose, proteins and urea are key substances for osmotic regulation. These molecules being inside or outside of the cell generate a larger or smaller osmotic gradient between intracellular and extracellular space.

Role of mineral salts in nervous system

The mineral salts play important role in the creation of electric voltage at cellular level. This cellular electric activity depends on the concentration of the cations and anions between inner and outer surfaces of the cell membrane. This is very important function which allows the neurons work.

Role of mineral salts in enzyme activity

pH regulation is very important because some enzymes work only under certain pH range. The mineral salts play important role pH regulation. Further, some minerals work as cofactors of enzymes and without them, enzymes cannot work.

Importance of Sodium

Sodium is a necessary ion in both plants and animals. In plants, it’s a micronutrient that aids in metabolism. It also serves as substitute for Magnesium for several functions in plants such as opening and closing of stomata. Excessive sodium in soil would result in lower water potential, reducing uptake of water from soil by plants.

In animals, Sodium is necessary for maintenance of electrolyte balance; fluid balance; generation of the nerve impulses, heart activity, blood volume, blood pressure, osmotic equilibrium, pH and many metabolic activities. In humans, table salt is the most important source of Sodium. A human needs half gram sodium every day, which can be obtained from 1.2 to 1.5 grams of table salt. However, generally we take more than that required amount. In excessive amount, salt would promote hypertension.

Hypernatremia, Hyponatremia and Thirst

In human body, the brain part hypothalamus and pituitary glands control the balance of sodium and water concentration in extracellular fluids. If a person loses too much body water, the sodium concentration in blood will rise higher than normal. The hypothalamus would sense it and would result in thirst. This condition is also known as Hypernatremia. On the other hand, if we drink lots of water, it would reduce concentration of sodium in blood, which is called Hyponatremia.  This would cause loss of water as urine. We note here that when a severally hydrated person is rescued from desert or ocean, he would have very high blood sodium concentration. This must be slowly and carefully treated because rapid correction of Hypernatremia can result in brain damage from cellular swelling.

Importance of Calcium

Calcium is present in almost all cells and plays important role in physiology and biochemistry in both plants and animals. In plants, Calcium and Potassium ions both work in tandem in the opening and closing of stomata. In some cases, Sodium can work in place of Potassium in case of deficiency of the later. Without Calcium, the mitotic spindle cannot form during cell division and thus needed for healthy plant growth. Further, Calcium ion is an essential component of cell walls and cell membranes. It is needed to stabilize the permeability of cell membranes. This is very important function in fruits where without Calcium; the cell walls would become weak and will not be able to hold the fruit content. Calcium is also stored in plants and provides some mechanical strength.

In animals and humans, Calcium plays important role in muscular contraction, blood coagulation, formation of bone tissue, teeth, motility of the sperm cells and transmission of the nerve impulses. Bones serve as storage site for Calcium and when needed, Calcium is released from Bones into blood. It remains in the blood as dissolved ion or bound to serum albumin. This function is controlled by Parathyroid gland and its parathyroid hormone.

Importance of Iodine

Iodine is needed for proper functioning of the thyroid. Iodine deficiency creates hypothyroidism also known as goitre.

Importance of Chloride

Like Sodium, chloride also actively participates in the osmotic regulation. Both sodium and chloride play important role in acid-base balance of an organism.