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Vitamin E reduces the oxidation of low–density lipoproteins (LDLs), and therefore its supplementation protects against atherosclerosis and reduces the risk of
developing cancer (Gibney et al. 2009; Ravisankar et al. 2015; Titchenal et al. 2018;
WHO/FAO 2004a). When the diet is supplemented with vitamin E, it resulted in the
mitogen stimulated increased T–lymphocyte multiplication, increased cytotoxic
cell activity and maximize the action of macrophages against the intruders thus
providing the strong basis of action against infections (Meydani et al. 2005; Pae
et al. 2012). Increased vitamin E content also inhibits the activation of protein
kinase C (PKC) enzyme which in turn leads to the reduced platelets, nitric oxide and
also reduced superoxide accumulation in macrophage cells and neutrophils (Azzi
et al. 2002). The deficiency of vitamin E in the body leads to the development of a
disease called ataxia (Jiang 2014). The main sources of vitamin E are nuts (almonds,
peanuts, hazelnuts), seeds, vegetable oils, wheat germ, green leafy vegetable and
fortified cereals.
Vitamin K These are a group of fat–soluble vitamins having a common
2–methyl–1,4–naphthoquinone nucleus but differ in the structures of a side chain at
the 3–position. They are synthesized by plants and bacteria. In plants the only
important molecular form is phylloquinone (vitamin K 1 ) with phytyl side chain.
Bacteria synthesize a group of compounds called menaquinones (vitamin K 2 ), which
have side chains based on repeating unsaturated 5–carbon (prenyl) units and menadione (K 3 ) which is analog of 1,4–naphthoquinone with a methyl group in the 2–
position. Vitamin K is critical for blood function, acting as coenzymes which play a
crucial role in the production of many proteins that are involved in blood coagulation and calcium homeostasis. The original term vitamin ‘K’ comes from German
word Koagulation (coagulation) meaning the ability to clot blood or prevent hemorrhage (Gibney et al. 2009; Ravisankar et al. 2015). Deficiency in vitamin K causes
bleeding disorders. The role of vitamin K 2 in osteoporosis, vascular calcification,
osteoarthritis, cancer, and cognition is studied by Schwalfenberg (2017) and its deficiency has been linked with vascular calcification and osteoporosis (Flore et al.
2013). However, vitamin K deficiencies are uncommon, but many drugs such as
antacids, blood thinners, antibiotics, aspirin, and drugs for cancer, seizures, high
cholesterol, and other conditions, can interfere with the effects of vitamin K (Chatron
et al. 2019). It has also been observed that people with liver or pancreatic disease,
celiac disease, or malabsorption conditions are at higher risk for vitamin K deficiency (Reddi et al. 1995; Kawashima et al. 1997). Signs and symptoms include
nose bleeding, easy bruising, broken blood vessels, bleeding gums, and heavy
menstrual bleeding in women. Vitamin K is found in highest concentrations in
green vegetables such as broccoli, cabbage, kale, parsley, spinach, and lettuce and it
can be synthesized via bacteria in the large intestine (Titchenal et al. 2018).
Vitamin K 2 supplementation is quite safe and does not induce hypercoagulation
(Asakura et al. 2001).
25 Bioavailability of Nutrients and Safety Measurements
Vitamin E reduces the oxidation of low–density lipoproteins (LDLs), and therefore its supplementation protects against atherosclerosis and reduces the risk of
developing cancer (Gibney et al. 2009; Ravisankar et al. 2015; Titchenal et al. 2018;
WHO/FAO 2004a). When the diet is supplemented with vitamin E, it resulted in the
mitogen stimulated increased T–lymphocyte multiplication, increased cytotoxic
cell activity and maximize the action of macrophages against the intruders thus
providing the strong basis of action against infections (Meydani et al. 2005; Pae
et al. 2012). Increased vitamin E content also inhibits the activation of protein
kinase C (PKC) enzyme which in turn leads to the reduced platelets, nitric oxide and
also reduced superoxide accumulation in macrophage cells and neutrophils (Azzi
et al. 2002). The deficiency of vitamin E in the body leads to the development of a
disease called ataxia (Jiang 2014). The main sources of vitamin E are nuts (almonds,
peanuts, hazelnuts), seeds, vegetable oils, wheat germ, green leafy vegetable and
fortified cereals.
Vitamin K These are a group of fat–soluble vitamins having a common
2–methyl–1,4–naphthoquinone nucleus but differ in the structures of a side chain at
the 3–position. They are synthesized by plants and bacteria. In plants the only
important molecular form is phylloquinone (vitamin K 1 ) with phytyl side chain.
Bacteria synthesize a group of compounds called menaquinones (vitamin K 2 ), which
have side chains based on repeating unsaturated 5–carbon (prenyl) units and menadione (K 3 ) which is analog of 1,4–naphthoquinone with a methyl group in the 2–
position. Vitamin K is critical for blood function, acting as coenzymes which play a
crucial role in the production of many proteins that are involved in blood coagulation and calcium homeostasis. The original term vitamin ‘K’ comes from German
word Koagulation (coagulation) meaning the ability to clot blood or prevent hemorrhage (Gibney et al. 2009; Ravisankar et al. 2015). Deficiency in vitamin K causes
bleeding disorders. The role of vitamin K 2 in osteoporosis, vascular calcification,
osteoarthritis, cancer, and cognition is studied by Schwalfenberg (2017) and its deficiency has been linked with vascular calcification and osteoporosis (Flore et al.
2013). However, vitamin K deficiencies are uncommon, but many drugs such as
antacids, blood thinners, antibiotics, aspirin, and drugs for cancer, seizures, high
cholesterol, and other conditions, can interfere with the effects of vitamin K (Chatron
et al. 2019). It has also been observed that people with liver or pancreatic disease,
celiac disease, or malabsorption conditions are at higher risk for vitamin K deficiency (Reddi et al. 1995; Kawashima et al. 1997). Signs and symptoms include
nose bleeding, easy bruising, broken blood vessels, bleeding gums, and heavy
menstrual bleeding in women. Vitamin K is found in highest concentrations in
green vegetables such as broccoli, cabbage, kale, parsley, spinach, and lettuce and it
can be synthesized via bacteria in the large intestine (Titchenal et al. 2018).
Vitamin K 2 supplementation is quite safe and does not induce hypercoagulation
(Asakura et al. 2001).
25 Bioavailability of Nutrients and Safety Measurements