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Vitamins – all you need to know


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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