USN Advice:
Supplements - All about Vitamins
Vitamins form the basic nuts and bolts that keep your system together.
It is no quick fix though, and should be taken regularly and constantly,
as is the case with many other nutrients. Lets have a closer look
at some vitamins and what they do.
1. Vitamin A (Retinol)
Named after the retina of the eye, retinol is an oil soluble
vitamin that is essential for vision (especially night vision),
the skin and mucous membranes, cell growth, reproduction, and
normal immunity. Sources of this vitamin are liver and fish liver
oils. Beta-carotene, the precursor of Vitamin A, can be found
in carrots and dark green leafy vegetables. One large carrot
for example contains 18 000 IU of beta-carotene, which is more
than three times the RDA of 1000mcg RE (retinol equivalents).
It takes 6 mcg of beta-carotene to yield 1 mcg RE of vitamin
A.
2. Vitamin B1 (Thiamin)
Thiamin is water-soluble and should be consumed daily. Thiamin
is involved in the supply of energy to the body from carbohydrates.
Sources of Thiamin are whole grains that are mostly processed
to such an extent that most or all of the Thiamin is lost. A
survey done by the United States Department of Agriculture showed
that 45% of all Americans are Thiamin deficient. This may be
good enough for the average couch potato, but not for someone
leading an active lifestyle trying to improve his energy production.
The RDA for Thiamin is only 1.5mg per day, but even at 500mg
per day, no toxicity was found in studies. A healthy guideline
to be used by active individuals to maintain the Thiamin status
in your body, will be 50 - 200mg / day.
3. Vitamin B2 (Riboflavin)
Riboflavin is another water soluble B-vitamin. Its main function
is to help the mitochondria of muscle cell to produce energy.
This means that it works in close relationship with Thiamin in
the energy supply chain.Sources of Riboflavin include meats,
poultry, fish, and dairy products in amounts that vary substantially.
Again, the processing of food can destroy up to 80% of Vitamin
B2.The RDA for Riboflavin is 1.7mg per day, but athletes can
use 25-200mg per day.
4. Vitamin B3 (Niacin)
In the body, the amino acid "Tryptophan" is
converted to Niacin. Niacin increases the use of glycogen in
the production of energy to working muscles, and therefore
is in higher demand by individuals that take part in physical
recreational activity. However, mega-doses of Niacin do cause
glycogen to be used quicker, but it blocks the use of fatty
acids for fuel. When glycogen depletion then occurs faster
than normal, fats are also unwilling sources of fuel. The RDA
for Niacin is 19mg per day but athletes can take 30-100mg per
day. Should you experience a flushing, burning or itchy sensation,
you may have OD'd, but within reasonable amounts (100mg) should
not be toxic. It is highly resistant to food processing, and
at RDA level, rarely deficient.
5. Vitamin B6 (Pyridoxine)
Pyridoxine functions at the level of
protein-, amino acid-, and hemoglobin synthesis. It is also
important for the enzyme "glycogen
phosphorylase", which adds a phosphor molecule to glycogen
to use it for fuel. It is thus important for energy supply, as
well as muscle and blood formation. You get Pyridoxine from wheat
germ, chicken, fish, and eggs. Although it is available in these
common food sources, 33% of households in the USA were found
to be Pyridoxine-deficient. Both the demand for energy and protein
synthesis increase the need for Pyridoxine. The RDA is 2.0mg
per day, but if you need to put on muscle mass, and you train
3 hours or more per day, you can double that figure. Over dosage
of 100mg or more for years may cause nerve damage.
6. Vitamin B5 (Pantothenic Acid)
Yet another water soluble vitamin that is needed in the making
of fatty acids and glucose, which forms the main sources of fuel
for the body. It is also essential for the making of steroid
hormones and neuro-transmitters in the brain.It is widely found
in foods and the RDA is only 6mg per day, but once again it will
not satisfy the needs of an athlete. You may want to consume
20mg to 200mg, which make supplementation the easiest way out.
Should you develop burning hot spots on your feet, and your sleeping
pattern become disturbed, you might be overdosing a bit.Pantothenic
Acid supplementation of 2.0g per day has shown to reduce lactate
build-up by 17% and oxygen consumption by 8%.
7. Folate (Folic Acid)
Folate forms part of vital coenzymes that control amino acid
metabolism. Insufficiency of folate will therefore inhibit growth
of new muscle and blood cells.Folate is widely found in dark
leafy vegetables, legumes (beans), and egg yolk. It is still
found to be deficient in many populations because it is very
susceptible to food processing and storage, which can kill up
to 80% of the vitamin.Although the official RDA is set for 200mcg
per day, it used to be 400mcg, which will still does not satisfy
the need for repair and growth in active individuals. Studies
has even shown that 211mcg per day is deficient for sedentary
people, let alone activity driven junkies. It is recommended
that at least 800mcg per day should be taken, although studies
indicated no adverse effects with a dosage of 10,000mcg per day
for four months.
8. Vitamin B12 (Cyanocobalamin)
This vitamin is an essential part of the coenzymes essential
for all cells, especially cells with a rapid turnover, like red
blood cells, the lining of the gastrointestinal tract, and bone
marrow cells. Deficiency is uncommon, which is lucky because
it will wipe out your nerves, and make you raving mad before
it kills you.Unfortunately for vegans, Vitamin B12 is only available
in animal foods. 8 to 10mcg or more per day should be enough,
although athletes taking 10,000 times the RDA showed no sign
of toxicity.
9. Biotin
Firstly, as part of the B-complex vitamins, it forms part of
two important enzymes, pyruvate carboxylase and acetyl-coenzyme
A carboxylase. These two are essential for gluconeogenesis (formation
of new glucose) and fatty acid synthesis, which forms two of
the major fuel sources for the body. Secondly another coenzyme
called 3-methylcrotonyl coenzyme A carboxylase is essential for
the breakdown of branched-chain amino acids, which means without
it the body cannot break down these amino acids to use them again
as building blocks for muscle.Deficiency of Biotin will speed
up the balding process, and leave you skinny and weak. Active
people should take 300 to 5000mcg daily, even though the RDA
specifies only 30-100mcg.The best food sources for Biotin are
liver, sardines, egg yolk, and soy flour. Raw egg whites as used
by some bodybuilders contain Avidin, which binds biotin and make
it useless for the body.
10. Vitamin C (Ascorbate)
This is certainly one of the best-known vitamins that is regularly
found on chemist shelves in different forms. The general application
of Vitamin C is to fight off scurvy by helping to form collagen,
the white fibres of your skin, bone, and connective tissue. You
only need 30mg of Vitamin C per day to prevent scurvy, but for
active individuals the key function of Vitamin C lies in its
antioxidant functions. You may use between 2 and 12 grams of
it per day if you lead a very active lifestyle, which would help
you to stay healthy and fight off the aging process.Citrus contains
Vitamin C in varied dosages, but just to be on the safe side,
supplement it regularly throughout the day to prevent acute shortages.
But don't only use the general Ascorbic Acid1 form of the vitamin;
also use a combination of Calcium Ascorbate2, Magnesium Ascorbate3,
and the fat soluble Ascorbyl Palmitate4. Overdosing with ascorbic
acid alone will certainly cause diarrhea.
11. Vitamin D (Cholecalciferol)
Vitamin D is a fat-soluble vitamin that is synthesized in the
skin when exposed to direct sunlight. It is important for bone
growth and the mineral balance in the body. The RDA is 10mcg
and because it is fat soluble, it can build up to toxic levels
in the body if only four times the RDA is taken.Fortified milk
and dairy products contains plenty Vitamin D, and it is seldom
insufficient in our diets.
12. Vitamin E (D-alpha-tocopherol)
The main function of Vitamin E is as an antioxidant, but food
processing destroys most of the vitamin E in food. Athletes could
take 400 to 2000 mg alpha TE (alpha tocopherol equivalents).
Vitamin E deficiency can lead to anemia even with ample supply
of Iron around, and it is also required for the metabolism of
Vitamin B12 and Zinc. This means that inadequate supply of Tocopherol
will result in weak and damaged red blood cells. As athletes
induce more damage to blood cells and muscle cells, there is
an increased demand to combat free radical damage to muscle during
and after exercise. It thus makes sense to supplement Vitamin
E together with folate, zinc, cobalamin, pyridoxine, and Ascorbate.
13. Vitamin K (Phylloquinone)
This fat-soluble vitamin is essential to make blood clot, which
makes it important for athletes because of their continual hemolysis
(blood loss) caused by exercise.Fresh green leafy vegetables
are the best source providing 50 to 800mcg per 100 grams. The
flora in the human gut also produces some Vitamin K. Physical
trauma like strenuous exercise increases the need for Vitamin
K, although it is uncertain how much is needed. 80 to 100mcg
should be sufficient, and since it is oil-soluble will build
up to toxic levels if over-dosed.
14. Choline
Choline is not a vitamin and your body can make it. Most of
your choline comes from your diet, and it is an essential part
of lecithin (phosphatidyl choline). Lecithin in turn is important
for the health of all the cell membranes. In the brain, choline
forms part of the neuro-transmitter acetylcholine which improves
your anabolic drive and memory. Your diet should include about
300mg, which should be met by the normal diet.
15. Inositol
Myo-inositol, which is its form in the body, forms part of
the lipids in your cell membranes. It is also important for normal
calcium - and insulin metabolism. Although it is uncertain how
much should be supplemented, some athletes are given 50 - 500mg
per day.
16. Coenzyme Q10 (Ubiquinone)
Coenzyme Q10 is essential for virtually
all energy production, by transferring electrons in the energy
cycle in the mitochondria (furnace) of the cell. It also helps
to maintain immunity, helps with normal heart function, and is
a potent antioxidant. CoQ occurs in many foods like polyunsaturated
vegetable oils, which the body converts to CoQ10. Activity junkies
with their high energy turnover, may need extra CoQ10. CoQ10 has
been associated with increased exercise tolerance in heart patients,
and well trained athletes showed an improvement of up to 12%. This
makes CoQ10 an important consideration for athletes seeking performance.
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