Vitamins
Vitamins are vital for human life because they play integral roles in hundreds
of life-sustaining biochemical reactions. Vitamins are the catalysts for all
reactions using proteins, fats and carbohydrates for energy, growth and cell
maintenance. Certain nutrients are required in excess of the typical amounts
supplied in the diet depending on specific nutritional needs. Consuming dietary
vitamin and mineral supplements may help play an important role in maintaining
good health. For the most part, vitamins cannot be produced in the body and must
be supplied through the diet or vitamin and mineral supplements.
Vitamin A has many important functions and
is:
-
Related
to helping to maintain normal vision in dim light and helping to prevent
night blindness.
-
Essential
for body growth, since it aids in the growth and formation of body cells. It
is especially needed for bone growth. If vitamin A intake is not sufficient,
bones will stop growing before the soft tissue is fully mature.
-
Necessary
to help normal tooth development. Enamel-forming cells are affected by the
absence of vitamin A.
-
Important
for helping to maintain healthy skin and mucous membranes. Without vitamin
A, the skin cells become dry and flat and gradually harden to form scales
that shed.
-
Necessary
to help support the health of the sex glands and uterus, as well as the
membranes which line the stomach, intestinal wall, bladder, and urinary
passages.
Vitamin
A is a fat soluble vitamin which is frequently found together in nature with
vitamin D. Cod Liver Oil is an excellent source of the combination of vitamins A
and D.
Vitamin D is necessary to help support the
growth, development and maintenance of bones and teeth in both adults and
children. It is also required for calcium and phosphorus absorption and
utilization. In its active form, vitamin D works with calcium to help control
bone formation. Vitamin D is unique in that it is obtained not only by eating
foods that contain vitamin D, it is also formed spontaneously in the skin, the
result of a photochemical reaction - caused by the sun - in the epidermis.
Foods
that contain vitamin D include oily fish, egg yolk, live yoghurt. Cod Liver Oil
is a good source of both Vitamin D and A.
Vitamin B
There are a large number of B vitamins - all involved in the process of the
metabolism of living cells. Working with proteins, they serve as coenzymes in
the various enzyme systems of the body. B vitamins must be replaced regularly
because they are water-soluble and are not stored in the body to any extent.
Also, because B vitamins work together synergistically, insufficient intake of
one or more B vitamins can hamper the utilization of others, causing an
imbalance to occur.
Vitamin B1 (thiamin) is a coenzyme involved
in the metabolic pathway which converts carbohydrates such as glucose into
energy. It is essential to help maintain the proper functioning of nerves,
muscles, the heart and the brain.
Vitamin B2 (riboflavin) is a coenzyme that
activates the breakdown and utilization of carbohydrates, fats and proteins. It
is essential to help produce cellular energy. Riboflavin is closely related to
the metabolism of protein and all functions requiring increases in protein such
as growth. Riboflavin is also essential to help maintain healthy eyes.
Vitamin B6 (pyridoxine) serves several
essential roles in the body. It is a coenzyme in protein metabolism. It is
needed to help in the conversion of tryptophan to niacin. It is also needed to
help in the formation of red blood cells. It facilitates the release of glycogen
for energy from the liver and muscles. It also participates in the utilization
of energy in brain and nervous tissue, thus being essential in helping to
regulate the central nervous system.
Vitamin B12 (cobalamin) is the only vitamin
that contains cobalt, a trace mineral. It is essential to help maintain the
normal functioning of all body cells, especially those of the bone marrow,
gastrointestinal tract, and nervous system. B12 is also necessary for forming
red blood cells. The metabolism of vitamin B12 is closely correlated with folate
(folic acid) metabolism.
Biotin (vitamin H) is an essential coenzyme
that assists in the synthesis and oxidation of fatty acids. It also aids in the
utilization of amino acids, folic acid, pantothenic acid (Vitamin B5) and
vitamin B12. It is also involved in the growth of healthy cells.
Choline is usually considered part of the
vitamin B complex. It is a component of lecithin, which helps facilitate the
movement of fat from the liver into cells. It must be present before vitamin A
can be stored. Choline is manufactured from the dietary phosphatides found in
lecithin.
Folic Acid functions as a coenzyme for
approximately 20 enzymes. It works with vitamins B12 and C in the utilization of
proteins. It is essential to the development of heme, the protein-containing
iron in haemoglobin needed to form red blood cells. Folic acid may also help
prevent neural tube defects in developing foetuses and is essential during
pregnancy. Some folic acid is produced by intestinal bacteria.
Inositol is usually considered part of the
vitamin B complex. Scientists believe that inositol, along with choline and
several B vitamins, may help in the metabolism of fat in the body.
Niacin (vitamin B3) and niacinamide are both
used by the body. Niacin is needed as a coenzyme in the production of energy.
Niacin is essential to help maintain the health of skin, nerves and the
digestive system.
Pantothenic acid plays a pivotal role in
energy production from fat, carbohydrate and protein. It is involved in the
formation of certain hormones and nerve regulating substances, and is
particularly supportive of the adrenal glands.
Vitamin C / Bioflavonoids
Vitamin C is also known as ascorbic acid and is a water-soluble, antioxidant
vitamin that plays a role in more than 300 bodily functions. It is essential to
help support health and wellness and requires daily replenishment.
Unfortunately, human beings - unlike most other animals - cannot manufacture
vitamin C. Nor can they store vitamin C to any appreciable amount. Instead, the
kidneys, acting as regulators, excrete vitamin C causing the need for regular
replenishment. In addition, vitamin C is destroyed during food preparation.
Vitamin C's primary function is to help maintain collagen, a protein necessary
for forming skin, ligaments, bones and teeth and for helping to maintain the
strength of blood vessel walls. High levels of vitamin C are also essential for
the metabolism of white blood cells, which are critical components of the immune
system. In addition, vitamin C plays an important role in the absorption of
iron, which is necessary for the formation of red blood cells and in the
utilization of folic acid, one of the B-complex vitamins.
Bioflavonoids work together with vitamin C to build strong capillaries and serve
as antioxidants and as anti-inflammatory agents.
Vitamin E (alpha tocopherol) was first
isolated from plant oils. Tocopherols are the primary fat-soluble antioxidants
that help minimize the effects of free-radicals.
Of the four compounds - designated as alpha, beta, delta and gamma tocopherols -
alpha tocopherol has the greatest nutritional and biological value. Vitamin E
(alpha tocopherol) may help:
-
Prevent
polyunsaturated fatty acids from breaking down and combining with substances
that may harm the body. As a result, fats and oils containing vitamin E are
less likely to turn rancid than those without vitamin E.
-
Prevent
oxygen from converting to toxic peroxide free radicals.
-
To
maintain muscle and nerve function.
-
Bring
nourishment to cells.
-
Strengthen
capillary walls.
-
Protect
red blood cells from being destroyed by poisons, such as hydrogen peroxide,
in the blood.
-
Promote
healthy immune function.
-
Decrease
platelet aggregation (thins blood).
Vitamin
K
Vitamin K is important to help support proper coagulation (blood clotting). The
liver uses vitamin K to synthesize blood-clotting proteins. Without vitamin K,
the level of the blood-clotting proteins drops, and clotting time is prolonged.
Vitamin K has also been recognized for its role in helping to maintain the
health of bones. There are three types of vitamin K:
Phylloquinone, which was discovered in
Denmark and termed vitamin K for the Danish word koagulation, is the natural
vitamin K found in alfalfa and other foods. It is known as K1.
Menaquinone, produced by intestinal
bacteria, is K2. Menadione, a synthetic compound with the basic structure of the
quinones, is K3.
Vitamin K is found in dark leafy greens, most green plants, alfalfa and kelp.
Blackstrap molasses and the polyunsaturated oils, such as safflower, also
contain some vitamin K. Animal sources of vitamin K include liver, milk, yoghurt,
egg yolks and fish liver oils.
Absorption of vitamin K takes place primarily in the upper part of the small
intestine with the help of bile or bile salts and pancreatic juices. It is then
carried to the liver for the synthesis of prothrombin, a key blood-clotting
factor.
Since natural vitamin K (K1) is fat soluble, it requires bile and pancreatic
juice in the intestine for optimal absorption. In contrast, some of the
synthetic vitamin K compounds (K3) are water soluble and more easily absorbed.
So people who do not tolerate natural vitamin K, such as those with decreased
bile acid secretion, may find K3 helpful.
Menaquinone (K2), which is produced by intestinal bacteria, may be the most
beneficial source of vitamin K. This is why vitamin K supplementation may be
particularly important for those whose normal balance of intestinal bacteria has
been disrupted.
The vitamin K available on this site is a highly tolerable, water-dispersible
version of vitamin K.
Minerals
Minerals are the inorganic elements which comprise part of the body. They
contribute from 60% to 80% of all the inorganic material in the human body. The
trace elements make up the remainder. Minerals and trace elements serve as vital
catalysts for the biological reactions that take place within the body. They are
found, for example, in bones, teeth and soft tissues. They are needed for the
production of blood, hormones and enzymes, thus serving a life sustaining
function.
The absorption of
minerals and trace elements (excluding electrolytes) is generally less efficient
than that of other nutrients. The term “bioavailability” refers to the
degree to which a particular nutrient is available for use in the body. There
are many factors which influence bioavailability including the compound form of
the mineral or trace element.
Boron
helps influence the metabolism of nutrients that help maintain bone health and
may play a role in hormone regulation.
Calcium is the most
abundant mineral in the body. Its primary function – in cooperation with
phosphorus – is to help build and maintain bones and teeth. Calcium aids the
blood-clotting process and helps control the passage of fluids through cells.
Calcium is also is related to proper functioning of the heart and neuromuscular
system.
Chromium,
when complexed as the Glucose Tolerance Factor, plays a role in the
effectiveness of insulin, the hormone responsible for blood sugar metabolism.
Copper
aids iron absorption, helping to form haemoglobin of red blood cells.
Copper also helps
convert amino acids into pigment, thereby adding colour to hair and skin.
Iodine
is an essential component of the thyroid hormone, thyroxine, which is the master
regulator of metabolism.
Iron
acts with protein and copper to make haemoglobin, the oxygen-carrying component
of red blood cells.
Magnesium
is involved in muscle contraction and nerve function. At least half of the
magnesium in the body is combined with calcium and phosphorus in bones. The
remainder is in soft tissues including red blood cells and muscles.
Manganese is an important activator of enzyme systems. It is involved in protein
synthesis and fatty acid metabolism. Manganese is also necessary for normal
skeletal development and pituitary gland activity.
Molybdenum
is a trace element that serves as a cofactor in many enzyme systems. It is also
involved in the physiological roles of sulfur-containing amino acids.
Phosphorus
is the second most abundant mineral in the body and is found in every living
cell. It is involved in helping the proper function of muscles and nerves and
often works in conjunction with calcium.
Selenium
is an essential trace mineral that works synergistically with vitamin E. As a
constituent of glutathione peroxidase, an antioxidant enzyme, selenium helps
neutralize the effects of free radicals within body tissue.
Sodium
and potassium are involved in the process
of balancing fluid within the body. Sodium is found predominantly in fluids
outside the cells, while potassium is found inside the cells. The balance of
these two electrolytes – along with calcium and magnesium – plays a vital
role in helping to maintain cardiovascular function.
Zinc
is an essential trace mineral, important to help support the immune system. It
is also a component of insulin, body fluids, and many enzyme systems.
Important
Notice Regarding Supplementation
For
many people, nutritional supplementation can be an important and useful adjunct
to a healthy diet. However, by no means should supplementation be a substitute
for food and it should also be recognised that certain nutrients should be used
within the recommended guidelines so as to reduce the possibility of toxicity or
side effects.
This
list is only offered as a general guide and is not to be viewed as a definitive
statement on the subject of drug-nutrient interactions or toxicity.
Caution
should always be used with individuals who are taking any form of drug therapy.
Ongoing
research will no doubt turn up additional information on the relationship
between optimum nutrient intake and overdose. If in doubt consult either an
authoritative text such as Martindale, Merck Index or the Royal Pharmaceutical
Society.
The
following may serve as a useful guide to some of the more common
contra-indications.
Vitamin A
Supplements containing above 2000i.u. (600mcg) should be avoided in pregnancy
and also by women planning pregnancy unless clinically indicated and supervised
by a healthcare professional.
Vitamin A may be contra-indicated in patients with kidney stones or a history of
kidney stones.
Vitamin A should be avoided by individuals sensitive to vitamin A.
Vitamin B
Prolonged use of isolated B vitamins at high levels may induce a deficiency in
some of the other B vitamins.
Individuals taking the drug L-Dopa should seek medical advice before taking B
Complex.
High intakes of vitamin B Complex can cause stomach cramps, nausea and diarrhoea.
Vitamin B1 above 75mg daily must be supervised by a doctor in patients with
diabetes and larger intakes (700-800mg) may cause drowsiness.
Vitamin B2 commonly causes a bright yellowing of the urine with larger intakes
possibly affecting laboratory blood tests.
Vitamin B3 (niacinamide) intake above 100mg may aggravate stomach ulcers,
glaucoma and diabetes with doses of one gram and above causing impairment of
liver function in some individuals.
Niacin intake above 100mg daily may cause a temporary flushing sensation.
Vitamin B6 in large levels over 100mg daily for a long period may cause numbness
in hands and feet together with headaches (peripheral neuritis)
Vitamin B6 above 20-30mg daily should be used only under supervision in
pregnancy.
High intakes of folic acid may mask vitamin B12 deficiency and vice versa.
Individuals taking Methotrexate should avoid folic acid in doses of 1mg and
above unless under supervision.
PABA (Para Amino Benzoic Acid) may interfere with the drug sulphonamide.
Vitamin B12 in high levels (mg doses) should be avoided in pregnancy and in
children under the age of twelve unless clinically indicated.
Vitamin C
High intake can cause diarrhoea, stomach cramps and flatulence.
Avoid supplementing over 1 gram of vitamin C daily if using the contraceptive
pill.
Vitamin C as ascorbic acid may aggravate stomach ulcers if used in high levels.
Long-term use of ascorbic acid at high intake levels may deplete calcium,
magnesium and potassium.
Potassium ascorbate is contra-indicated in kidney disease and hyperkalemia.
High intakes of vitamin C may interfere with some cytotoxic drugs used in cancer
therapy.
Medical advice should be taken if individuals are on drug therapy before taking
large doses of vitamin C and before blood tests.
Vitamin E
Intakes above 100i.u. in individuals with high blood pressure should initially
be used with caution.
Individuals taking anticoagulant drugs such as Warfarin, Heparin and Coumarin
should avoid vitamin E above 100mg daily unless supervised by a medical
practitioner.
Individuals with a recent history of heart disease should avoid excessive
intakes of vitamin E unless supervised by a medical practitioner.
Women with active breast, ovarian or hormonally dependent tumours should avoid
high intakes of vitamin E presented in a base of wheatgerm, soy, corn oil or
other polyunsaturated oils.
Boron
Calcium
Chromium
Iron
-
Iron
can accumulate in the system and long-term use should be monitored.
Contra-indicated in cases of Addisons Disease.
-
Inorganic
iron supplements can cause diarrhoea alternating with constipation and
stomach cramps.
-
Inorganic
iron supplements can cause dark brown to black bowel motions.
Magnesium
-
Contra-indicated
in kidney disease.
-
Can
cause diarrhoea, nausea and sometimes headaches when taken in large doses.
Manganese
Molybdenum
Potassium
Selenium
Zinc
