Categories: Vitamins

Functions of Vitamins

RDA versus ODA

The Recommended Daily Allowance (RDA) was instituted over forty years ago by the Food and Nutrition Board to determine what daily amount of vitamins were necessary to prevent disease. Unfortunately, what they came up with only gives us the bare minimum to ward off such diseases as beri beri, rickets, scurvy, and night blindness. What it does not account for is the amount needed to maintain maximum health rather than borderline health.

Current scientific studies indicate that larger dosages of these vitamins help our bodies work better. By providing an Optimum Daily Allowance (ODA) of vitamins, we can enhance our own health. This entails taking a larger percentage of what the RDA recommends. By using each dosage properly, a vitamin program can be designed that is custom-tailored for the individual. The RDAs are too generalized and cannot easily be obtained from today’s foods.

Balance and Synergy

Taking vitamins and minerals in their proper balance is important to the proper functioning of all vitamins. Scientific research has proven that an excess of an isolated vitamin or mineral can produce the same symptoms as a deficiency of that vitamin or mineral. For example, high doses of isolated B vitamins are proven to cause depletion of other B vitamins. Zinc must also be taken in the proper amounts. When taken in excess, this mineral causes symptoms of zinc deficiency. Synergy is the combination of two or more vitamins in order to create a stronger vitamin function.

For example, in order for bioflavanoids to work properly (they prevent bruising and bleeding gums), they must be taken along with vitamin C. In addition, there are certain substances that block the absorption and effects of vitamins. For example because the absorption of vitamin C is greatly reduced while taking antibiotics, more supplementation is necessary at this time. Vitamins and minerals should be taken with meals unless specified otherwise: oil-soluble vitamins should be taken before meals, and water-soluble ones should be taken between or after meals.

Chemical versus Natural

Synthetic vitamins are vitamins produced in a laboratory from isolated chemicals that mirror their counterparts found in nature. Although there are no major chemical differences between a vitamin found in food and one created in a laboratory, natural supplements do not contain other unnatural ingredients. Supplement that are not labeled natural may include coal tars, artificial coloring, preservatives, sugars, starch, as well a other additives. The buyer should beware of such harm fat elements. However, the shopper should also note that a “”natural vitamin”” bottle may contain vitamin that have not been extracted from a natural food source.

Studies have shown that protein bonded supple merits are absorbed, utilized, and retained in the tissue better than supplements that are not protein bonded Vitamins and minerals in food are bonded to proteins, lipids, carbohydrates, and bioflavonoids. Dr. Abram Hoofer explains: Components [of food] do not exist free in nature; nature does not lay down pure protein, pure fat, or pure carbohydrates. Their molecules are interlaced in a very complex three dimensional structure which even now has not been fully described. Intermingled are the essential nutrients such as vitamins and minerals, again not free, but combined in complex molecules. Using a natural form of vitamins and minerals in nutritional supplements is the objective of the protein bonding process. Taking the supplements with meals will supply the missing nutrients needed for better assimilation as well.

Available Products

Over-the-counter vitamins come in various forms, combinations, and amounts. They are available in tablet, capsule, powder, sublingual, lozenge, and liquid form. In most cases, it is a matter of personal preference as to how they are taken; however, due to slight variations in how rapidly the supplements are absorbed and assimilated into the body, some form form may be better than another. Vitamin supplements are usually available as isolated vitamins or in combination with other nutrients. For good health maintenance it is important to take them in natural complexes, rather than as artificial concentrates that can sometimes be used for crisis intervention. The amount you take should be based upon your own requirements.

A program designed for health maintenance would be different from one designed to overcome a specific disorder. If you find one supplement that meets your needs, remember to take it daily. If it does not contain a large enough quantity of what you want, you may consider taking more than one. Just make sure that you are aware of the increased dosage of the other nutrients it may contain. If there is no single supplement that provides you with what you are looking for, consider taking a combination of different supplements. Because the potency of most vitamins may be decreased by sunlight make sure that the container holding your vitamins is dark enough to shield its contents properly. Some people may be sensitive to plastic, and may need to purchase glass containers. Vitamins should be kept in a cool, dark place.

Vitamins From A to Z

Vitamin A (beta-Carotene)

This supplement prevents night blindness and other eye problems as well as some skin disorders such as acne. Enhances immunity, may heal gastrointestinal nice protects against pollution and cancer formation, and needed for epithelial tissue maintenance and repair. It is important in the formation of bones and teeth, aids fat storage, and protects against colds, influenza, and infections. Vitamin A acts as an antioxidant, which helps protect the cells against cancer and other disease This important vitamin also slows the aging process. Protein cannot be utilized by the body without this supplement. When food containing beta-carotene is consumed, it’s converted to vitamin A in the liver. Beta-carotene at in cancer prevention, according to recent reports. No vitamin overdose can occur with beta-carotene, though the skin may turn slightly yellow-orange color.

Sources: Vitamin A can be found in fish liver oils, animal live and green and yellow fruits and vegetables. Foods that contain significant amounts include alfalfa, apricot asparagus, beets, broccoli, cantaloupe, carrots, Swiss chard, dandelion greens, fish liver oil and liver, garlic, kale, mustard, papayas, parsley, peaches, red peppy sweet potatoes, spinach, spirulina, pumpkin and yellow squash, turnip greens, and watercress.

Warnings: Vitamin A should not be taken in large amounts in p form or as cod liver oil by those suffering from liver disease. Pregnant women should avoid amounts of vitamin A over 25,000 IU. Children taking vitamin A For more than one month should avoid amounts eve 18,000 IU. Antibiotics, laxatives, and some cholesterol lowering drugs interfere with vitamin A absorption. Diabetics should avoid beta-carotene as should hypothyroid individuals, because they cannot convert beta-carotene to vitamin A.

Vitamin B Complex

The B vitamins help to maintain healthy nerves, so eyes, hair, liver, and mouth, as well as muscle tone in gastrointestinal tract. B-complex vitamins are co-enzymes involved in energy production and may be useful for depression or anxiety. The B vitamins should always be taken together but up to two to three times more of one B vitamin than another can be taken for a particular disorder. Although the B vitamins are a team, they will be discussed individually. Vitamin Bl (Thiamine) Thiamine enhances circulation and assists in the production of hydrochloric acid, blood formation, and carbohydrate metabolism. Thiamine affects energy, growth disorders, and learning capacity, and is needed for normal muscle tone of the intestines, stomach, and heart.

Sources: Food sources of thiamine include dried beans, brown rice, egg yolks, fish, organ meats (liver), peanuts, peas, pork, poultry, rice bran, soybeans, wheat germ, and whole grains. Other sources are asparagus, beans, broccoli, Brussels sprouts, most nuts, oatmeal, plums, dried prunes, and raisins.

Warnings: Antibiotics, sulfa drugs, and oral contraceptives may decrease thiamine levels in the body. A high-carbohydrate diet increases the need for thiamine. Beriberi, a nervous system disease, is caused by a thiamine deficiency.

Vitamin B2 (Riboflavin)

Riboflavin is necessary for red blood cell formation, antibody production, cell respiration, and growth. It alleviates eye fatigue and is important in the prevention and treatment of cataracts. It aids in the metabolism of carbohydrates, fats, and proteins. When used with vitamin A, it maintains and improves the mucous membranes in the digestive tract. Riboflavin also facilitates oxygen use by the body tissues (skin, nails, hair), eliminates dandruff, and helps the uptake of iron and vitamin B6.

Vitamin B2 is important during pregnancy because a lack of this vitamin may damage the fetus even though the mother may be unaware of a deficiency. B2 is needed for the metabolism of tryptophan, which is converted to niacin in the body. Carpet tunnel syndrome may benefit from a treatment program that includes riboflavin and B6. Deficiency symptoms include cracks and sores at the corner of the mouth. Deficiency symptoms include cracks and sores at the corner of the mouth.

Sources: Vitamin B2 is found in the following food products: beans, cheese, eggs, fish, meat, milk, poultry, spinach, and yogurt. Other sources include asparagus, avocados, broccoli, Brussels sprouts, currants, and nuts.

Warnings: Factors that increase the need for riboflavin include use of oral contraceptives and strenuous exercise. This B vitamin is easily destroyed by light, cooking, antibiotics, and alcohol.

Vitamin B3 (Niacin, Niacinamide, Nicotinic Acid)

Vitamin B3 is needed for proper circulation and healthy skin. B3 aids in the functioning of the nervous system, in the metabolism of carbohydrates, fats, and proteins, and in the production of hydrochloric acid for the digestive system. Niacin lowers cholesterol and improves circulation. B3 is also effective in the treatment of schizophrenia and other mental illnesses.

Sources: Niacin and niacinamide are found in beef, broccoli, carrots, cheese, corn flour, eggs, fish, milk, pork, potatoes, tomatoes, and whole wheat.

Warnings: A flush, usually harmless, may occur after ingestion of niacin; a red rash will appear on the skin and a tingling sensation may be experienced as well. High amounts should be used with caution by those who are pregnant and those suffering from gout, peptic ulcers, glaucoma, liver disease, and diabetes.

Pantothenic Acid (B5)

Known as the “”antistress”” vitamin, pantothenic acid plays a role in the production of the adrenal hormones and formation of antibodies, aids in vitamin utilization, and helps to convert fats, carbohydrates, and proteins into energy. This vitamin is needed to produce vital steroids and cortisone in the adrenal gland, and is an essential element of coenzyme A. It is required by all cells in the body and is concentrated in the organs. It is also needed for normal functioning of the gastrointestinal tract and may be helpful in treating depression and anxiety.

Sources: The following foods contain pantothenic acid beans, beef, eggs, saltwater fish, mother’s milk, pork, fresh vegetables, and whole wheat.

Warnings: No side effects have been documented to date.

Vitamin B6 (Pyridoxine)

Pyridoxine is involved in more bodily functions than any other single nutrient. It affects both physical and mental health. It is beneficial if you suffer from water retention. It is necessary in the production of hydrochloric acid and the absorption of fats and protein. Pyridoxine also aids in maintaining sodium and potassium balance, and promotes red blood cell formation. It is required by the nervous system, and is needed for normal brain function and for the synthesis of RNA and DNA (nucleic acids), which contain the genetic instructions for the reproduction of all cells and for normal cellular growth.

It activates many enzymes and aids in B12 absorption, immune system function, and antibody production. Vitamin B6 has a role in cancer immunity and arteriosclerosis. It inhibits the formation of a toxic chemical called homocysteine, which attacks the heart muscle and allows the deposition of cholesterol around the heart muscle. Be may also be useful in preventing oxalate kidney stones and acts as a mild diuretic. It reduces the symptoms of premenstrual syndrome and is helpful in the treatment of allergies, arthritis, and asthma. Carpal tunnel syndrome is linked to a B6 deficiency.

Sources: All foods contain small amounts of vitamin B6; however, the following foods have the highest amounts: brewer’s yeast, carrots, chicken, eggs, fish, meat, peas, spinach, sunflower seeds, walnuts, and wheat germ. Other sources not quite as rich in B6 include avocado, bananas, beans, blackstrap molasses, brown rice and other whole grains, cabbage, and cantaloupe.

Warnings: Antidepressants, estrogen, and oral contraceptives may increase the need for vitamin B6 in the body.

Vitamin B12 (Cyanocobalamin)

Vitamin B12 is needed to prevent anemia. It aids in cell formation and cellular longevity. This vitamin is also required for proper digestion, absorption of foods, protein synthesis, and metabolism of carbohydrates and fats. In addition, vitamin B12 prevents nerve damage, maintains fertility, and promotes normal growth and development. A vitamin B12 deficiency can be caused by malabsorption, which is most common in the elderly and in those with digestive disorders. Vegetarians are else more likely to have a B12 deficiency. Deficiency symptoms include abnormal gait, memory loss, hallucinations, eye disorders, anemia, and digestive disorders.

Sources: The largest amounts of vitamin B12 are found in blue cheese, cheese, clams, eggs, herring, kidney, liver, mackerel, milk, seafood, and tofu. B12 is not found in vegetables; it is available only from animal sources.

Warnings: Anti-gout medications, anticoagulant drugs, and potassium supplements may block absorption of B12 in the digestive tract. Vegetarians need this supplement because it is found mostly in animal sources.


Biotin aids in cell growth, in fatty acid production, in the metabolism of carbohydrates, fats, and proteins, and in the utilization of the B-complex vitamins. Sufficient quantities are needed for healthy hair and skin. Biotin may prevent hair loss in some men. Biotin also promotes healthy sweat glands, nerve tissue, and bone marrow. A deficiency of this B vitamin is rare because it can be produced in the intestines from foods.

Sources: Biotin is found in cooked egg yolk, saltwater fish, meat, milk, poultry, soybeans, whole grains, and yeast.

Warnings: Raw egg whites contain a protein called ovidin, which combines with biotin in the intestinal tract and depletes the body of this needed nutrient. A dry, scaly scalp and/or face in infants, called seborrheic dermatitis, may indicate a deficiency. Consuming rancid fats or saccharin inhibits biotin absorption. The use of sulfa drugs and antibiotics threatens the availability of biotin.


Choline is needed for nerve transmission, gallbladder regulation and liver function, and lecithin formation. It minimizes excess fat in the liver, aids in hormone production, and is necessary in fat and cholesterol metabolism. Without choline, brain function and memory are impaired. Choline is beneficial for disorders of the nervous system such as Parkinson’s disease and tardive dyskinesia. A deficiency may result in fatty buildup in the liver.

Sources: The following foods contain a significant amount of choline: egg yolks, legumes, meat, milk, and whole grain cereals.

Warnings: No side effects have been documented to date.

Folic Acid

Considered a brain food, folic acid is needed for energy production and the formation of red blood cells. Functioning as a coenzyme in DNA synthesis, it is important for healthy cell division and replication. It is involved in protein metabolism and has been used in the prevention and treatment of folic acid anemia. This nutrient may also help depression and anxiety and may be effective in the treatment of uterine cervical dysplasia. Folic acid helps regulate embryonic and fetal development of nerve cells, vital for normal growth and development. Folic acid works best when combined with vitamin B12. A sore, red tongue is one sign of a deficiency.

Sources: The following foods contain significant quantities of folic acid: barley, beans, beef, bran, brewer’s yeast, brown rice, cheese, chicken, dates, green leafy vegetables, lamb, lentils, liver, milk, oranges, organ meats, split peas, pork, root vegetables, salmon, tuna, wheat germ, whole grains, whole wheat, and yeast.

Warnings: Oral contraceptives may increase the need for folic acid. High doses for extended periods should be avoided by anyone with a hormone-related cancer or convulsive disorder.


Inositol is vital for hair growth. It helps prevent hardening of the arteries and is important in lecithin formation and fat and cholesterol metabolism. It also helps remove fats from the liver.

Sources: Inositol is found in fruits, vegetables, whole grains, meats, and milk.

Warnings: Drinking heavy amounts of caffeine may cause a shortage of inositol in the body.

PABA (Para-Aminobenzoic Acid)

PABA is one of the basic constituents of folic acid and also helps in the utilization of pantothenic acid. This antioxidant helps protect against sunburn and skin cancer, acts as a coenzyme in the breakdown and utilization of protein, and assists in the formation of red blood cells. Supplementing the diet with PABA may restore gray hair to its original color if the graying was caused by stress or a nutritional deficiency.

Sources: Foods that contain PABA are kidney, liver, molasses, and whole grains.

Warnings: Sulfa drugs may cause a deficiency of PABA.

Vitamin C (Ascorbic Acid)

Vitamin C is an antioxidant that is required for tissue growth and repair, adrenal gland function, and healthy gums. It protects against the harmful effects of pollution, prevents cancer, protects against infection, and enhances immunity. It also may reduce cholesterol levels and high blood pressure, and prevent atherosclerosis. Essential in the formation of collagen, vitamin C protects against blood clotting and bruising, and promotes the healing of wounds and the production of anti-stress hormones. It also aids in interferon production, and is needed for the metabolism of folic acid, tyrosine, and phenylalanine. New evidence indicates that vitamin C and vitamin E work synergistically, that is, when they work together, they have a greater effect than when they work separately.

Vitamin E scavenges for dangerous oxygen radicals in the cell membrane, while vitamin C breaks the free radical chain in biologic fluids. Both these vitamins greatly extend antioxidant activity. Ester C polyascorbate is a breakthrough in vitamin C, especially for those suffering from chronic illnesses such as cancer and AIDS This form of vitamin C (esterified) was first researched by Jonathan Wright, M.D. Dr. Wright proved that white blood cell ascorbate levels are increased four times more with ester C than with the average vitamin C or ascorbic acid, and only one-third of the amount is excreted through the urine. Because the body cannot manufacture vitamin C, it must be obtained through the diet or in the form of supplements.

Most vitamin C intake is lost in the urine. Then larger amounts of vitamin C are required due to illness, it is more effective to take vitamin C intravenously than to take high doses orally. Do so only under the advisement and supervision of your doctor. Ester C enters the bloodstream and tissues four times quicker and into the blood cells more efficiently. This is a big step for the immune system. Ester C has naturally chelated (bonded) minerals that allow faster absorption. It comes in calcium, magnesium, potassium, zinc, and sodium forms. These polyascorbate pH balanced forms are manufactured according to exact specifications.

Sources: Vitamin C is found in green vegetables, berries, and citrus fruits. It is found in asparagus, avocados, beet greens, broccoli, Brussels sprouts, cantaloupe, collards, currants, grapefruit, kale, lemons, mangos, mustard greens, onions, oranges, papayas, parsley, green peas, sweet peppers, persimmons, pineapple, radishes, rose hips, spinach, strawberries, Swiss chard, tomatoes, turnip greens, and watercress.

Warnings: Aspirin, alcohol, analgesics, antidepressants, anticoagulants, oral contraceptives, and steroids may reduce levels of vitamin C in the body. Diabetic (diabinase) and sulfa drugs may not be as effective when taken with vitamin C. Large amounts may cause a false negative reading when testing for blood in the stool. Pregnant women should use amounts no larger than 5,000 milligrams daily. Infants may become dependent on this supplement and develop scurvy.

Vitamin D

Vitamin D is required for calcium and phosphorus Absorption and utilization. It is necessary for growth, and is especially important for normal growth and development of bones and teeth in children. It is important in the prevention and treatment of osteoporosis, rickets and hypocalcemia, and it enhances immunity. The vitamin D that we get from food or supplements is not fully activated It requires conversion by the liver, and then by the kidney before it becomes fully active. People with liver or kidney disorders are at a higher risk for osteoporosis. Because the sun’s ultraviolet rays can be converted to vitamin D, exposing the face and arms to the sun three times a week is effective.

Sources :Fish liver oils, fatty saltwater fish, dairy products fortified with vitamin D, and eggs all contain vitamin D. It is found in alfalfa, butter, cod liver oil, egg yolk, halibut, liver, milk, oatmeal, salmon, sardines, sweet potatoes, tuna, and vegetable oils. Vitamin D can be converted from the action of sunlight on the skin.

Warnings: Toxicity may occur from amounts over 65,000 IU over a period of years. Vitamin D should not be taken without calcium. Intestinal disorders and liver and gallbladder malfunctions interfere with absorption of vitamin D. The use of some cholesterol-lowering drugs, antacids, mineral oil, or steroid hormones (cortisone) also interferes with absorption. Thiazide diuretics disturb the calcium vitamin D ratio.

Vitamin E

Vitamin E is an antioxidant that prevents cancer and cardiovascular disease. This supplement improves circulation, repairs tissue, and is useful in treating fibrocystic breasts and premenstrual syndrome. It also promotes normal clotting and healing, reduces scarring from some wounds, reduces blood pressure, aids in preventing cataracts, improves athletic performance, and aids leg cramps. Vitamin E also prevents cell damage by inhibiting lipid per oxidation and the formation of free radicals. It retards aging and may prevent age spots as well. The body needs zinc in order to maintain the proper levels of vitamin E in the blood.

Sources: Vitamin E is found in the following food sources: cold- pressed vegetable oils, whole grains, dark green leafy vegetables, nuts and seeds, and legumes. Significant quantities of this vitamin are also found in dry beans brown rice, cornmeal, eggs, desiccated liver, milk, oat meal, organ meats, sweet potatoes, and wheat germ. Vitamin E is found in the following food sources; cold pressed vegetable oils, whole grains dark green leafy vegetables, nuts and seeds, and legumes. Quantities of this vitamin are also found in dry beans, brown rice, cornmeal, eggs, desiccated liver, milk, oat meal, organ meats, sweet potatoes, and wheat germ.

Warnings: Do not take iron at the same time that you take vitamin E Those suffering from diabetes rheumatic heart disease or an overactive thyroid should not use high doses. Those suffering from high blood pressure should start with a small amount and increase slowly to the desired amount.

Vitamin K

Vitamin K is needed for blood clotting and may play a role in bone formation. It may also prevent osteoporosis. In addition, vitamin K converts glucose into glycogen for storage in the liver.

Sources: Vitamin K is found in alfalfa, broccoli, dark green leafy vegetables, and soybeans. Other foods that contain vitamin K include blackstrap molasses, Brussels sprouts, cabbage, cauliflower, egg yolks, liver, oatmeal, oats, rye, safflower oil, and wheat.

Warnings: When synthetic vitamin K is used in large doses during the last few weeks of pregnancy, it may result in a toxic reaction in the newborn. Megadoses can accumulate and cause flushing and sweating. Antibiotics interfere with the absorption of vitamin K.


Although Bioflavonoids are not true vitamins in the strictest sense, they are sometimes referred to as vitamin P. Bioflavonoids enhance absorption of vitamin C, and they should be taken together. There are many products and mixtures of different bioflavonoids including hesperetin, hesperidin, eriodictyol, quercetin, quercetrin, and rutin. The human body cannot produce bioflavonoids, which must be supplied in the diet. They are used extensively in athletic injuries because they relieve pain, bumps, and bruises. They also reduce pain located in the legs or across the back and lessen symptoms associated with prolonged bleeding and low serum calcium.

Bioflavonoids act synergistically with vitamin C to protect and preserve the structure of capillary blood vessels. In addition, bioflavonoids have an antibacterial effect and promote circulation, stimulate bile production, lower cholesterol levels, and treat and prevent cataracts. When taken with vitamin C, bioflavonoids also reduce the symptoms of oral herpes. Quercetin, found in blue-green algae and available as a supplement, may effectively treat and prevent asthma symptoms. Bromelin and quercetin are synergisms, and should be taken in conjunction to enhance absorption. Take 1,000-2,000 milligrams of quercetin daily in 3-6 divided doses for asthma or allergies

Sources: The white material just beneath the peel of citrus fruits, peppers, buckwheat, and black currants contain bioflavonoids. Sources of vitamin F include apricots, cherries, grapefruit, grapes, lemons, oranges, prunes, and rose hips.

Warnings: Extremely high doses may cause diarrhea.

Coenzyme Q10

Coenzyme Q,0 is a vitamin-like substance that resembles vitamin E, but which may be an even more powerful antioxidant. It is also called ubiquinone. There are ten common coenzyme Qs, but coenzyme Q10 is the only one found in human tissue. Coenzyme Q10 declines with age and should be supplemented in the diet. It plays a crucial role in the effectiveness of the immune system and in the aging process. The New England Institute reports that coenzyme Q alone is effective in reducing mortality in experimental animals afflicted with tumors and leukemia. Clinical tests are being used along with chemotherapy to reduce the side effects of the drugs.

In Japan, it is used in the treatment of heart disease and high blood pressure, and is also used to enhance the immune system. Research has revealed that use of coenzyme Q,10 benefits allergies, asthma, and respiratory disease, and it is used to treat the brain for anomalies of mental function such as those associated with schizophrenia and Alzheimer’s disease. It is also beneficial in aging, obesity, candidiasis, multiple sclerosis, periodontal disease, and diabetes. AIDS is a primary target for research on coenzyme Q10 because of its immense benefits to the immune system.

Early research in Japan has shown coenzyme Q10 to protect the stomach lining and duodenum. It may help heal duodenal ulcers. Coenzyme Q,10 has the ability to counter histamine and is valuable to allergy and asthma sufferers. The use of coenzyme Q,10 is a major step forward in the prevention and control of cancer. Be cautious when purchasing coenzyme Q,10. Not all products will offer it in its purest form. Its natural color is bright yellow and has very little taste in the powdered form. It should be kept away from heat and light. Pure coenzyme Q,10 will deteriorate in temperatures above 115F.

Sources: Mackerel, salmon, and sardines contain the largest amounts of coenzyme Q10.

Warnings: No side effects have been documented to date.

Author: Life Enthusiast Staff