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Minerals are key elements of the body. They are needed in the buildup and function
of important biomolecules in the human body. Although, minerals are not a source
of energy in the body but they are necessary for the maintenance of normal biochemical processes in the body (Zhao et al. 2016). Based on the body needs, these
essential minerals can be classified as either a macro or micro (trace) minerals.
9.4.1 Macro-Minerals
Macro-minerals are nutritionally important minerals such as sodium, calcium,
phosphorus, magnesium and potassium. They are classified as macro because the
average adult daily requirement is greater than 100 mg/day (Prashanth et al. 2015).
9.4.1.1 Calcium
It is obtained from hard water, shellfish, fish, dark green leafy vegetables and milk
(Jeurnink and De Kruif 1995). Calcium is a mineral which is essential for an adequate growth and bone development (Matkovic and Ilich 1993). It is a common
mineral found in blood (McCarron and Reusser 1999). Cells require an adequate
amount of calcium to perform various functions (Miller et al. 2001). Teeth and
bones are rich in calcium (Vallet-Regí and González-Calbet 2004). It is also involved
in blood clotting (Hall et al. 1991). Most of the calcium is found in bones (Reid
et al. 2015). The total extracellular fluid space contains about 900 mg of calcium
which is in dynamic equilibrium with the skeleton (Bronner and Stein 1995). About
1% of the skeletal calcium (10 g) is readily exchangeable with the calcium in extracellular fluids and constitutes a large calcium reservoir. The remaining 99% of the
bone calcium is only slowly exchangeable. Nearly 500 mg of calcium are deposited
in and mobilized from the bones daily in a continuous process of remodelling.
Calcium is secreted into the intestine through bile, pancreatic juice, and intestinal
secretion but is completely reabsorbed. As the blood level of calcium decreases,
bones start to release calcium to increase the calcemia. When the calcium level
increases in the blood, it is deposited in bones or excreted in urine. Calcium is
involved in the nerve function, contraction of muscles and clotting of blood. Its level
in blood is maintained by the parathyroid hormone and calcitonin. The dailyrecommended allowance for calcium is 1 g per day. Vitamin D is involved in the
uptake of calcium by the body. Its deficiency results in rickets, osteoporosis, and
osteomalacia. Tetany may occur due to the deficiency of calcium in the blood.
Causes of hypocalcaemia include chronic renal failure (Naveh-Many et al. 1995),
phosphate therapy etc. (Välimäki et al. 1999). The excess amount of calcium in the
blood can result in the development of kidney stones (Pettifor 2008; Sahay and
Sahay 2012).
M. Akram et al.
Minerals are key elements of the body. They are needed in the buildup and function
of important biomolecules in the human body. Although, minerals are not a source
of energy in the body but they are necessary for the maintenance of normal biochemical processes in the body (Zhao et al. 2016). Based on the body needs, these
essential minerals can be classified as either a macro or micro (trace) minerals.
9.4.1 Macro-Minerals
Macro-minerals are nutritionally important minerals such as sodium, calcium,
phosphorus, magnesium and potassium. They are classified as macro because the
average adult daily requirement is greater than 100 mg/day (Prashanth et al. 2015).
9.4.1.1 Calcium
It is obtained from hard water, shellfish, fish, dark green leafy vegetables and milk
(Jeurnink and De Kruif 1995). Calcium is a mineral which is essential for an adequate growth and bone development (Matkovic and Ilich 1993). It is a common
mineral found in blood (McCarron and Reusser 1999). Cells require an adequate
amount of calcium to perform various functions (Miller et al. 2001). Teeth and
bones are rich in calcium (Vallet-Regí and González-Calbet 2004). It is also involved
in blood clotting (Hall et al. 1991). Most of the calcium is found in bones (Reid
et al. 2015). The total extracellular fluid space contains about 900 mg of calcium
which is in dynamic equilibrium with the skeleton (Bronner and Stein 1995). About
1% of the skeletal calcium (10 g) is readily exchangeable with the calcium in extracellular fluids and constitutes a large calcium reservoir. The remaining 99% of the
bone calcium is only slowly exchangeable. Nearly 500 mg of calcium are deposited
in and mobilized from the bones daily in a continuous process of remodelling.
Calcium is secreted into the intestine through bile, pancreatic juice, and intestinal
secretion but is completely reabsorbed. As the blood level of calcium decreases,
bones start to release calcium to increase the calcemia. When the calcium level
increases in the blood, it is deposited in bones or excreted in urine. Calcium is
involved in the nerve function, contraction of muscles and clotting of blood. Its level
in blood is maintained by the parathyroid hormone and calcitonin. The dailyrecommended allowance for calcium is 1 g per day. Vitamin D is involved in the
uptake of calcium by the body. Its deficiency results in rickets, osteoporosis, and
osteomalacia. Tetany may occur due to the deficiency of calcium in the blood.
Causes of hypocalcaemia include chronic renal failure (Naveh-Many et al. 1995),
phosphate therapy etc. (Välimäki et al. 1999). The excess amount of calcium in the
blood can result in the development of kidney stones (Pettifor 2008; Sahay and
Sahay 2012).
M. Akram et al.