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Vitamin A Vitamin A is a group of unsaturated compounds that includes retinoids.
β– retinol, retinal, retinoic acid and pro vitamin A like carotenoids (β–carotene)
(Tanumihardjo 2002). It occurs naturally in food stuffs of animal sources like fish,
beef, liver, eggs, and dairy products. Green leafy vegetables and fruits serve as plant
sources for carotenoids that can be converted into retinol. Vitamin A plays a key role
in enhancing eye sight, growth, reproduction, blood cells formation and improves
body’s immune response (Hinds et al. 1997; Akram et al. 2011; Mahan and Raymond
2016; Titchenal et al. 2018). Vitamin A not only supports the vision of eyes but also
maintains the coverings and linings of the eyes and other tissues. As an antioxidant,
vitamin A protects cellular membranes, helps in maintaining glutathione levels, and
influences the amount and activity of enzymes that scavenges free radicals. It is
released into the blood bound to a retinol–binding protein, which transports it to
cells. According to WHO, the vitamin A deficiency affects 127 million preschool
children worldwide which results in increased risks of mortality and morbidity from
measles and diarrheal infections, night blindness, and anemia. Among women
vitamin A deficiency is likely to be associated with high mortality related to pregnancy. So, its consumption in daily diet should be increased according to dietary
reference intake’s (DRI) recommended values (Gibney et al. 2009; Aslam et al.
2017; Titchenal et al. 2018; Akram et al. 2011).
Vitamin B Complex Vitamin B complex consists of several different compounds
that are grouped according to their functional distinctions (Hellmann and Mooney
2010). The members of B complex include thiamine (B 1 ), riboflavin (B 2 ), niacin
(B 3 ), pantothenic acid (B 5 ), pyridoxine (B 6 ), biotin (B 7 ), folic acid (B 9 ) and cobalamins (B 12 ) (Roje 2007). As discussed below, vitamin B complex (combined) and its
individual constituents are used to promote the defensive role for prevention of
diseases by boosting–up the immune system (Aslam et al. 2017).
Vitamin B 1 (Thiamin) Thiamin or thiomene plays an important function in glucose metabolism and acts as a cofactor for enzymes that break down glucose for
energy production. It is used in the synthesis of neurotransmitters and is thus
required for RNA, DNA, and ATP synthesis. The brain and heart are most affected
by thiamin deficiency (beriberi) while other symptoms are fatigue, confusion,
impaired movement, pain in the lower extremities, swelling, and heart failure.
Another common thiamin deficiency known as Wernicke–Korsakoff syndrome
causes beriberi like symptoms such as confusion, loss of coordination, vision
changes, hallucinations, leading to coma and death. Whole grains, meat and fish are
excellent natural sources of thiamin (Gibney et al. 2009; Mahan and Raymond
2016; Titchenal et al. 2018).
Vitamin B 2 (Riboflavin) Riboflavin is an essential component of flavoproteins,
which are involved in various pathways of carbohydrate, lipid, and protein metabolism. Flavoproteins aid in the transfer of electrons in the electron transport chain.
When riboflavin is taken in excess amounts as supplement, the excess is excreted
through kidneys. Riboflavin deficiency, sometimes referred to as ariboflavinosis, is
often accompanied by other dietary deficiencies associated with the majority of the
K. Sharma et al.
Vitamin A Vitamin A is a group of unsaturated compounds that includes retinoids.
β– retinol, retinal, retinoic acid and pro vitamin A like carotenoids (β–carotene)
(Tanumihardjo 2002). It occurs naturally in food stuffs of animal sources like fish,
beef, liver, eggs, and dairy products. Green leafy vegetables and fruits serve as plant
sources for carotenoids that can be converted into retinol. Vitamin A plays a key role
in enhancing eye sight, growth, reproduction, blood cells formation and improves
body’s immune response (Hinds et al. 1997; Akram et al. 2011; Mahan and Raymond
2016; Titchenal et al. 2018). Vitamin A not only supports the vision of eyes but also
maintains the coverings and linings of the eyes and other tissues. As an antioxidant,
vitamin A protects cellular membranes, helps in maintaining glutathione levels, and
influences the amount and activity of enzymes that scavenges free radicals. It is
released into the blood bound to a retinol–binding protein, which transports it to
cells. According to WHO, the vitamin A deficiency affects 127 million preschool
children worldwide which results in increased risks of mortality and morbidity from
measles and diarrheal infections, night blindness, and anemia. Among women
vitamin A deficiency is likely to be associated with high mortality related to pregnancy. So, its consumption in daily diet should be increased according to dietary
reference intake’s (DRI) recommended values (Gibney et al. 2009; Aslam et al.
2017; Titchenal et al. 2018; Akram et al. 2011).
Vitamin B Complex Vitamin B complex consists of several different compounds
that are grouped according to their functional distinctions (Hellmann and Mooney
2010). The members of B complex include thiamine (B 1 ), riboflavin (B 2 ), niacin
(B 3 ), pantothenic acid (B 5 ), pyridoxine (B 6 ), biotin (B 7 ), folic acid (B 9 ) and cobalamins (B 12 ) (Roje 2007). As discussed below, vitamin B complex (combined) and its
individual constituents are used to promote the defensive role for prevention of
diseases by boosting–up the immune system (Aslam et al. 2017).
Vitamin B 1 (Thiamin) Thiamin or thiomene plays an important function in glucose metabolism and acts as a cofactor for enzymes that break down glucose for
energy production. It is used in the synthesis of neurotransmitters and is thus
required for RNA, DNA, and ATP synthesis. The brain and heart are most affected
by thiamin deficiency (beriberi) while other symptoms are fatigue, confusion,
impaired movement, pain in the lower extremities, swelling, and heart failure.
Another common thiamin deficiency known as Wernicke–Korsakoff syndrome
causes beriberi like symptoms such as confusion, loss of coordination, vision
changes, hallucinations, leading to coma and death. Whole grains, meat and fish are
excellent natural sources of thiamin (Gibney et al. 2009; Mahan and Raymond
2016; Titchenal et al. 2018).
Vitamin B 2 (Riboflavin) Riboflavin is an essential component of flavoproteins,
which are involved in various pathways of carbohydrate, lipid, and protein metabolism. Flavoproteins aid in the transfer of electrons in the electron transport chain.
When riboflavin is taken in excess amounts as supplement, the excess is excreted
through kidneys. Riboflavin deficiency, sometimes referred to as ariboflavinosis, is
often accompanied by other dietary deficiencies associated with the majority of the
K. Sharma et al.