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9.4.1.2 Sodium
Sodium (natrium) is present in most foods and its dietary deficiency is rare. Sodium
is involved in the control of blood. Sodium chloride is the most common form of
sodium which is marketed as table salt (Cogswell et al. 2016). Kidneys are the main
regulators of body sodium and normally 98% of the body loss of sodium occurs in
urine. If more sodium is ingested, its excretion in the urine increases. If less sodium
is ingested or if plasma sodium falls due to any reason, sodium may totally disappear from the urine. This is usually through the adrenocortical hormone aldosterone, which increases the tubular reabsorption of sodium in the renal tubules. An
increased level of sodium in the blood defines hypernatremia, and is characterized
by seizures, oedema, neuromuscular excitability, irritability, weakness and lethargy
(Kalogeropoulos et al. 2015; Xi et al. 2015).
9.4.1.3 Magnesium
Magnesium is obtained from hard water, spices, apricots, bananas, soybeans, nuts,
green leafy vegetables, and whole grains. It aids in the maintenance of bone growth
and integrity and is involved in the regulation of the cardiac cycle and the functioning of muscles and nerves. Deficiency diseases are hypomagnesaemia and neuromuscular irritability. Toxicity symptoms are hypotension, respiratory failure, and
cardiac disturbances (Allen and Sharma 2019; Gragossian and Friede 2019).
9.4.1.4 Potassium
It is obtained from whole and skimmed milk, meat, bananas, raisins and prunes. A
proper plasma potassium level is essential for the normal heart functioning.
Potassium ions also take part in the normal functioning of skeletal muscle fibers.
Potassium is needed for many enzyme reactions (Weaver 2013). Glycogenesis
requires the presence of potassium. Insulin administration causes a fall in plasma
potassium level because the deposition of glycogen brought about by insulin is also
accompanied by the deposition of potassium. Moreover, insulin also increases protein synthesis within the cells, which by binding potassium ions can lead to a low
plasma potassium level. Potassium deficiency leads to hypokalemia, paralysis, and
cardiac disturbances. Excessive potassium levels lead to hyperkalemia, paralysis
and cardiac disturbances (He and MacGregor 2008).
9.4.1.5 Phosphorus
It is obtained from legumes, nuts, cereals, fish, meat, cheese and poultry (Takeda
et al. 2012). The bioavailability of minerals such as iron and zinc may be low in a
total vegetarian diet because of the presence of substances such as phytic acid.
Besides, large amounts of dietary fiber may interfere with its proper absorption.
9 Vitamins and Minerals: Types, Sources and their Functions
9.4.1.2 Sodium
Sodium (natrium) is present in most foods and its dietary deficiency is rare. Sodium
is involved in the control of blood. Sodium chloride is the most common form of
sodium which is marketed as table salt (Cogswell et al. 2016). Kidneys are the main
regulators of body sodium and normally 98% of the body loss of sodium occurs in
urine. If more sodium is ingested, its excretion in the urine increases. If less sodium
is ingested or if plasma sodium falls due to any reason, sodium may totally disappear from the urine. This is usually through the adrenocortical hormone aldosterone, which increases the tubular reabsorption of sodium in the renal tubules. An
increased level of sodium in the blood defines hypernatremia, and is characterized
by seizures, oedema, neuromuscular excitability, irritability, weakness and lethargy
(Kalogeropoulos et al. 2015; Xi et al. 2015).
9.4.1.3 Magnesium
Magnesium is obtained from hard water, spices, apricots, bananas, soybeans, nuts,
green leafy vegetables, and whole grains. It aids in the maintenance of bone growth
and integrity and is involved in the regulation of the cardiac cycle and the functioning of muscles and nerves. Deficiency diseases are hypomagnesaemia and neuromuscular irritability. Toxicity symptoms are hypotension, respiratory failure, and
cardiac disturbances (Allen and Sharma 2019; Gragossian and Friede 2019).
9.4.1.4 Potassium
It is obtained from whole and skimmed milk, meat, bananas, raisins and prunes. A
proper plasma potassium level is essential for the normal heart functioning.
Potassium ions also take part in the normal functioning of skeletal muscle fibers.
Potassium is needed for many enzyme reactions (Weaver 2013). Glycogenesis
requires the presence of potassium. Insulin administration causes a fall in plasma
potassium level because the deposition of glycogen brought about by insulin is also
accompanied by the deposition of potassium. Moreover, insulin also increases protein synthesis within the cells, which by binding potassium ions can lead to a low
plasma potassium level. Potassium deficiency leads to hypokalemia, paralysis, and
cardiac disturbances. Excessive potassium levels lead to hyperkalemia, paralysis
and cardiac disturbances (He and MacGregor 2008).
9.4.1.5 Phosphorus
It is obtained from legumes, nuts, cereals, fish, meat, cheese and poultry (Takeda
et al. 2012). The bioavailability of minerals such as iron and zinc may be low in a
total vegetarian diet because of the presence of substances such as phytic acid.
Besides, large amounts of dietary fiber may interfere with its proper absorption.
9 Vitamins and Minerals: Types, Sources and their Functions