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properties (Christakos et al. 2015; Gaman et al. 2019). Ageing decreases the capacity of the skin to produce vitamin D 3 . After the age of 70, vitamin D levels decrease
to about 25% of the normal value in adults (Kennel et al. 2010). In the temperate
zone, the cutaneous production of vitamin D 3 is limited by the reduced ultraviolet
radiations availability. In the absence of solar exposure, about 400–600 IU of vitamin D seems to be required daily to maintain the normal bone metabolism.
Deficiency of vitamin D can affect bone development. In children, vitamin D deficiency causes rickets, a disorder in which bones deteriorate and bend under pressure. In adults, vitamin D deficiency results in osteomalacia (soft bones) which
enhances the risk of bones fractures (Kennel et al. 2010; Nair and Maseeh 2012;
Christakos et al. 2015).
9.3.1.3 Vitamin E
Vitamin E is an anti-sterility factor and a natural antioxidant. Structurally related
names of vitamin E include tocopherols or tocotrienols (Gheorghe et al. 2019). It is
involved in the healing of wounds and in immunity. Sources of vitamin E include
wheat germ oil, nuts, cereals, meat, eggs, milk, green leafy vegetables, and other
vegetables. The deficiency of vitamin E is associated in humans with cystic fibrosis, ataxia and abetalipoproteinemia (disorder that interferes with the normal
absorption of fat and fat-soluble vitamins from food) and with habitual abortions
and testicular degeneration in laboratory animals. Also, vitamin E deficiency can
lead to increased hemolysis of the red blood cells and macrocytic anaemia in premature infants. The effects of excessive vitamin E doses lead to interference with
the utilization of vitamins A and K, prolonged prothrombin time, intestinal irritability, headache, fatigue, and dizziness (Schmölz et al. 2018; Birringer et al. 2019;
Gomez-Pomar et al. 2018; Moisa et al. 2018; Kemnic and Coleman 2019; Reddy
and Jialal 2018).
9.3.1.4 Vitamin K
The major function of vitamin K is the formation of prothrombin in the liver along
with other vitamin K dependent clotting factors namely: VII, IX,, X, protein C and
S which are essential for normal blood coagulation or blood clotting. It is found in
fresh green leafy vegetables, lettuce, cabbage, egg yolk, soybean oil, and liver.
Our body can also produce its own vitamin K courtesy of the normal bacterial
flora of our intestines. Premature babies receive 0.5–1 mg vitamin K intramuscularly or 1–2 mg orally at birth to prevent Vitamin K deficiency. Vitamin K deficiency can result to generalized bleeding, the development of hemorrhagic disease
of the newborn, and prolonged clotting time in adults. Excessive doses of vitamin
K can lead to hyperbilirubinemia in infants and vomiting in adults (Reddy and
Jialal 2018).
M. Akram et al.
properties (Christakos et al. 2015; Gaman et al. 2019). Ageing decreases the capacity of the skin to produce vitamin D 3 . After the age of 70, vitamin D levels decrease
to about 25% of the normal value in adults (Kennel et al. 2010). In the temperate
zone, the cutaneous production of vitamin D 3 is limited by the reduced ultraviolet
radiations availability. In the absence of solar exposure, about 400–600 IU of vitamin D seems to be required daily to maintain the normal bone metabolism.
Deficiency of vitamin D can affect bone development. In children, vitamin D deficiency causes rickets, a disorder in which bones deteriorate and bend under pressure. In adults, vitamin D deficiency results in osteomalacia (soft bones) which
enhances the risk of bones fractures (Kennel et al. 2010; Nair and Maseeh 2012;
Christakos et al. 2015).
9.3.1.3 Vitamin E
Vitamin E is an anti-sterility factor and a natural antioxidant. Structurally related
names of vitamin E include tocopherols or tocotrienols (Gheorghe et al. 2019). It is
involved in the healing of wounds and in immunity. Sources of vitamin E include
wheat germ oil, nuts, cereals, meat, eggs, milk, green leafy vegetables, and other
vegetables. The deficiency of vitamin E is associated in humans with cystic fibrosis, ataxia and abetalipoproteinemia (disorder that interferes with the normal
absorption of fat and fat-soluble vitamins from food) and with habitual abortions
and testicular degeneration in laboratory animals. Also, vitamin E deficiency can
lead to increased hemolysis of the red blood cells and macrocytic anaemia in premature infants. The effects of excessive vitamin E doses lead to interference with
the utilization of vitamins A and K, prolonged prothrombin time, intestinal irritability, headache, fatigue, and dizziness (Schmölz et al. 2018; Birringer et al. 2019;
Gomez-Pomar et al. 2018; Moisa et al. 2018; Kemnic and Coleman 2019; Reddy
and Jialal 2018).
9.3.1.4 Vitamin K
The major function of vitamin K is the formation of prothrombin in the liver along
with other vitamin K dependent clotting factors namely: VII, IX,, X, protein C and
S which are essential for normal blood coagulation or blood clotting. It is found in
fresh green leafy vegetables, lettuce, cabbage, egg yolk, soybean oil, and liver.
Our body can also produce its own vitamin K courtesy of the normal bacterial
flora of our intestines. Premature babies receive 0.5–1 mg vitamin K intramuscularly or 1–2 mg orally at birth to prevent Vitamin K deficiency. Vitamin K deficiency can result to generalized bleeding, the development of hemorrhagic disease
of the newborn, and prolonged clotting time in adults. Excessive doses of vitamin
K can lead to hyperbilirubinemia in infants and vomiting in adults (Reddy and
Jialal 2018).
M. Akram et al.