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Sunday, January 22, 2012

What is a vitamin? A healthy vitamin review of the 13 universally recognized vitamins

What is a vitamin? A healthy vitamin review of the 13 universally recognized vitamins

Vitamins are essential for the normal growth and development of a multicellular organism. They are organic compounds that for the most part, are obtained with food, and are required for LIFE. Vitamins are essential nutrients because they are needed for the healthy maintenance of the cells, tissues, and organs that make up the body and enable it to efficiently use chemical energy provided by food it eats. Vitamins help process the proteins, carbohydrates, and fats required for cellular activity. When vitamins are deficient, they are associated with acute and chronic illness and even death. Sadly, vitamins cannot be formed in sufficient quantities by the body and need to be obtained from the diet, so in today’s fast paced world and industrialization it behooves us to pay attention to the nutrients that may be washed away with over- processing and over farming of food.

Vitamins have diverse biochemical functions such as:

1. Hormone-like function: as regulators of mineral metabolism - vitamin D
2. Regulators of cell and tissue growth and differentiation - vitamin A
3. Antioxidants - vitamin E and vitamin C
4. Precursors for enzyme cofactors, that help enzymes do their work as facilitators for a healthy metabolism

The term vitamin does not include other essential nutrients such as dietary minerals, essential fatty acids, or essential amino acids. These are also needed yet in even larger amounts. There is even another group of large number of nutrients that promote health yet are otherwise required less often. I will discuss these in a later blog.

Vitamins are classified as either water-soluble or fat-soluble. In humans there are 13 vitamins: 4 fat-soluble (A, D, E, and K) and 9 water-soluble (8 B vitamins and vitamin C). Water-soluble vitamins dissolve easily in water and, in general, are readily excreted from the body. Because they are not readily stored, consistent daily intake is important.

Fat-soluble vitamins are absorbed through the intestinal tract with the help of fats. Because they are fat soluble, the body has a harder time eliminating them, and are more likely to accumulate in the body and even pose toxicity risk.

Vitamins are classified by their biological and chemical activity, not their structure. Therefore, each "vitamin" refers to a number of different sub- compounds that show the biological activity associated with that particular vitamin. These sub-compounds are called ‘vitamers’. By definition, vitamers can be converted to the active form in the body, and are sometimes inter-convertible within one another, as well.

Sources of vitamins are plenty and our own body can help in synthetize some as well. For example, vitamin D can be produced in the skin with the help of the natural ultraviolet wavelength of sunlight. Another example is vitamin A where the body can produce it from substrates such as beta carotene; and vitamin B3, niacin, can be made from the amino acid tryptophan. One very important source of vitamins are the microorganisms that live in the intestine known as "gut flora" — they produce vitamin K and biotin among other very important nutrients.

Vitamin storages in the body are also important. For example, vitamins A, D, and B12 are stored in significant amounts in the liver. The fat is another storage place for some vitamins. A person’s diet may be deficient in vitamins A and D for many months and B12 in some cases for years, before developing an overt deficiency condition. Vitamin C deficiency, also called scurvy, presents within a month to 6 months after being deprived. This depends on the individual person’s storage ability. Another example is vitamin B3, niacin and its metabolite niacinamide. It is not stored in the human body in significant amounts, so stores may last only a couple of weeks and symptoms of deficiency may start relatively soon after depravation.

When talking about vitamin deficiencies, they are classified as either primary or secondary. A primary deficiency occurs when the body does not get enough of the vitamin in the food. A secondary deficiency is possible when a person has an underlying disorder that prevents or limits the absorption of the vitamin due to a “lifestyle intervention”, such as smoking, excessive alcohol consumption, or the use of medications that interfere with the absorption or use of the vitamin. People who eat a varied diet are unlikely to develop a severe primary vitamin deficiency. In contrast, prolonged restrictive diets and surgeries such as gastric bypass surgery have the potential to cause sustained vitamin deficits, which may result in often painful and potentially deadly diseases. Overt deficiencies are rare in the developed world as there is ample supply of food, and government mandated ‘fortification’ or the addition and supplementation of foods are a norm.


Here is the list of the 13 universally recognized vitamins at present. They are named in alphabetical order, and describe the main actions, adequate daily intake, common sources, what is expected when there is a deficiency, and presents the typical features when there is toxicity. I have also added the usual reason to use for treatment and prevention of several medical issues. Please remember that in this blog I do not intend to diagnose or treat any medical condition, and I only suggest that you visit with your doctor if you have further questions.

VITAMIN A: Retinol, Retinal and Carotenoids

a. Fat Soluble

b. Main actions: Vision: and aids in the adaptation of the retina to changes in light –making vision better at night. Vitamin A is key to gene expression, maintenance of healthy mucosae, and strengthens the immune system. It supports growth and development, and red blood cell production. Aids in growth hormone production, promotes healthy thyroid function and may offer some protection against cancer- topical vitamin A can help prevent basal cell carcinoma.

c. When deficient: Night blindness, Hyperkeratosis and Ketomalacia

d. Adequate intake: 600- 3000 mcg/day – or 2,000-10,000 IU/d

e. Sources: Vitamin A is only found in animal tissues. Its precursor beta-carotene can be found in Oranges, orange vegetables, carrots, pumpkin, squash, spinach, fish liver oils, milk, eggs and fortified foods.

f. Use in treatment and prevention: Vitamin A is used to treat retinitis pigmentosa, acute promyelocytic leukemia, and skin diseases such as psoriasis, acne and eczema.

g. Toxicity: Signs of toxicity are associated with long-term consumption of vitamin A in excess of ten times the RDA (8,000 to 10,000 mcg/day or 25,000 to 33,000 IU/day). The condition caused by vitamin A toxicity is called hypervitaminosis A. Preformed vitamin A is rapidly absorbed as it is fat soluble and slowly cleared from the body. Acute vitamin A toxicity is relatively rare, and symptoms include nausea, headache, and fatigue, loss of appetite, dizziness, dry skin, desquamation, and cerebral edema.

h. Use in treatment and prevention. Vitamin A is used at pharmacologic doses to treat several conditions, including retinitis pigmentosa, acute promyelocytic leukemia, and various skin diseases.

VITAMIN B1: Thiamine

a. Water soluble

b. Main actions: Thiamine is a required coenzyme for a small number of very important enzymes, it is also important in the cellular metabolism and proper functioning of the mitochondria. It is also required for the synthesis of the nucleic acids, DNA and RNA, and the niacin-containing coenzyme NADPH, which is essential for a number of biosynthetic reactions

c. When deficient: Thiamin deficiency affects the cardiovascular, nervous, muscular, and gastrointestinal systems. The disease Beriberi (dry or wet) is caused by thiamine deficiency: a person presents with decreased sensation and weakness in the legs and arms and severe neuropathy, burning feet and exaggerated reflexes when severe it may cause seizures., Wet beriberi involves the heart and presents with rapid heart rate, enlargement of the heart, severe swelling, difficulty breathing, and ultimately congestive heart failure. Wernicke-Korsakoff Syndrome is also due to thiamine deficiency. Deficiency is most seen in alcoholics.

d. Adequate intake: 1.2 mg/dayu to 100 mg/day

e. Sources: Found in yellow fruit and leafy vegetables, carrots, yams, cantaloupe, organ meats (liver), lean pork, poultry, beans, peas, soybeans, and other legumes, wheat germ, brown rice, oatmeal, rice, kale, cauliflower, potatoes, nuts, , and yeast are rich sources of thiamin

f. Use in treatment and prevention: Thiamine has been used to prevent cataracts, Alzheimer’s dementia, and congestive heart failure. The use of thiamin in cancer is controversial.

g. Toxicity: there are no well-established toxic effects from the consumption of excess thiamine in food or through long-term oral supplementation (up to 200 mg/day).

VITAMIN B2: Riboflavin

a. Water soluble

b. Main actions: In the body, riboflavin is primarily found as an integral component of the coenzymes for oxidation and reduction reactions needed for the metabolism of carbohydrates, fats, and proteins. Riboflavin also participates in the metabolism of drugs and toxins via cP450 in the liver, and is key for the absorption and metabolism of iron in the body

c. When deficient: Riboflavin deficiency may present with sore throat, redness and swelling of the lining of the mouth and throat, cracks or sores on the outsides of the lips (cheliosis) and at the corners of the mouth (angular stomatitis), inflammation and redness of the tongue (magenta tongue), and a moist, scaly skin inflammation (seborrheic dermatitis). Women of child bearing age that are deficient in riboflavin are 4.7 times more likely to develop preeclampsia than those who had adequate riboflavin

d. Adequate intake: 1.3 mg/day up to 100mg/day

e. Sources: Dairy products, bananas, popcorn, green beans, asparagus, yet most plant and animal derived foods contain at least small quantities of riboflavin. B2 will break down when exposed to light.

f. Use in treatment and prevention: Riboflavin has been used to treat migraines and prevent cataracts.

g. Toxicity: No toxic or adverse effects of high riboflavin intake in humans are known.

VITAMIN B3: Niacin / Niacinamide also known as nicotinic acid

a. Water soluble

b. Main actions: Niacin is an integral component of the coenzymes for oxidation and reduction reactions needed for the metabolism of carbohydrates, fats, and proteins. Niacin is important for G-proteins that act as intermediaries in multiple cell functions. It is vital for energy release from the cells, and the maintenance of the nervous and digestive system. It is essential for growth and cholesterol balance.

c. When deficient: The most common symptoms of niacin deficiency involve the skin, digestive system, and the nervous system. These symptoms are commonly referred to as the four D's: dermatitis, diarrhea, dementia, and death. In the skin, a thick, scaly, darkly pigmented rash develops symmetrically in areas exposed to sunlight. Symptoms related to the digestive system include a bright red tongue, vomiting, and diarrhea. Neurologic symptoms include headache, apathy, fatigue, depression, disorientation, and memory loss. The late stage of severe niacin deficiency is called Pellagra and it can be lethal.

d. Adequate intake: 16 mg/day up to 100 mg/day

e. Sources: Good sources of niacin include yeast, meat, poultry, red fishes (e.g., tuna, salmon), eggs, many green leafy vegetables, mushrooms, tree nuts, cereals (especially fortified cereals), legumes, seeds, milk, coffee, and tea. The body can also produce it from the amino acid tryptophan.

f. Use in treatment and prevention: Niacin is commonly used in the prevention and treatment of cholesterol issues, and in cancer prevention, particularly leukemia. A recent study found that higher levels of niacin intake were associated with decreased progression rate to AIDS and improved survival.

g. Toxicity: Niacin from foods is not known to cause adverse effects. Common side effects of nicotinic acid include flushing, itching, and gastrointestinal disturbances such as nausea and vomiting. Liver damage is also a possible side effect after prolonged high dose use.

VITAMIN B5: Pantothenic acid

a. Water Soluble

b. Main actions: Pantothenic acid is found throughout living cells in the form of coenzyme A (CoA), a vital coenzyme in numerous chemical reactions required to generate energy from food (fat, carbohydrates, and proteins). CoA is required for the production of the neurotransmitter, acetylcholine, and the hormone, melatonin. CoA is also important in the metabolism of a number of drugs and toxins by the liver. It aids in weight management, would healing, and cholesterol balance.

c. When deficient: A deficiency can present with headache, fatigue, insomnia, intestinal disturbances, numbness and painful burning and tingling in the feet, yet, naturally occurring pantothenic acid deficiency in humans is very rare and has been observed only in cases of severe malnutrition.

d. Adequate intake: 5 mg/day up to 50mg/day

e. Sources: Rich sources of pantothenic acid include meat, liver, kidney, chicken, broccoli, avocados, yeast, egg yolk, fish, shellfish, milk, yogurt, legumes, mushrooms, and sweet potatoes and brewers yeast

f. Use in treatment and prevention: Administration of oral pantothenic acid and application of pantothenol ointment to the skin have been shown to accelerate the closure of skin wounds and increase the strength of scar tissue in animals. It also has a cholesterol lowering effect.

g. Toxicity: Pantothenic acid is not known to be toxic in humans.

VITAMIN B6: Pyridoxine, Pyridoxamine, Pyridoxal

a. Water Soluble

b. Main actions: Vitamin B6 plays a vital role in the function of approximately 100 enzymes that catalyze essential chemical reactions in the human body, particularly in the handling of glucose in the liver: from getting it from glycogen stores to generating it via gluconeogenesis. B6 is essential in the brain to synthesize neurotransmitters such as serotonin, dopamine, norepinephrine and gamma-aminobutyric acid (GABA) all required for adequate brain function and the production of red blood cells. It is key in hormonal regulation of estrogen and progesterone as it binds at the receptor site and it has a function in maintaining normal skin.

c. When deficient: Large observational studies have associated low vitamin B6 intake or status with increased blood homocysteine levels and increased risk of cardiovascular diseases yet overt B6 deficiency is rare. A person may present with scaly dermatitis, irritability, depression, and confusion, inflammation of the tongue, sores or ulcers of the mouth, and ulcers at the corners of the mouth have been reported. Anemia, Peripheral neuropathy can also happen in severe cases.

d. Adequate intake: 1.3 to 1.7 mg/day up to 50 mg/day

e. Sources: Meat, salmon, turkey, spinach, green vegetables, tree nuts, bananas, and hazelnuts

f. Use in treatment and prevention: Vitamin B6 in treatment doses has been used to help eczema, dermatitis, anxiety, depression, and premenstrual syndrome, morning sickness and carpal tunnel syndrome. For prevention, vitamin B6 can be used to increase homocysteine and improve and prevent heart disease, improve the immune system, and maximize cognitive function. It has been reported that B6 may help reduce risk for kidney stones.

g. Toxicity: B6 is a water-soluble vitamin and is excreted in the urine therefore toxicity is rare. Long-term supplementation with very high doses of pyridoxine may result in pain and numbness in the extremities, and sensory neuropathy

VITAMIN B7: Biotin

a. Water Soluble

b. Main actions: Biotin is attached at the active site of five mammalian enzymes known as carboxylases and each carboxylase catalyzes an essential metabolic reaction, such as with Acetyl-coA for the formation of essential fatty acids, with pyruvate carboxylase for gluconeogenesis, among others.

c. When deficient: Signs of overt biotin deficiency include hair loss and a scaly red rash around the eyes, nose, mouth, and genital area –Dermatitis. , Neurologic symptoms in adults have included depression, lethargy, hallucination, and numbness and tingling of the extremities.

d. Adequate intake: 30 mcg/day

e. Sources: Egg yolk, liver, peanuts and yeast are rich sources of biotin

f. Use in treatment and prevention: It has well been recognized in helping reduce birth defects, improve glucose handling in diabetics, improve hair health and reduce hair loss and improve the appearance and strength of the nails

g. Toxicity: Biotin is not known to be toxic.

VITAMIN B9: Folic Acid and Folinic

a. Water Soluble

b. Main actions: Folate coenzymes play a vital role in DNA metabolism through two different pathways. 1) The synthesis of DNA from its precursors (thymidine and purines) is dependent on folate coenzymes. 2) A folate coenzyme is required for the synthesis of methionine, and methionine is required for the synthesis of S-adenosylmethionine (SAM). SAM is a methyl group (one-carbon unit) donor used in many biological methylation reactions, including the methylation of a number of sites within DNA and RNA. Folate coenzymes are required for the metabolism of several important amino acids.

c. When deficient: Rapidly dividing cells are most vulnerable to the effects of folate deficiency; thus, when the folate supply is inadequate, blood cell division becomes abnormal resulting in fewer but larger red blood cells. This type of anemia is called megaloblastic or macrocytic anemia, referring to the enlarged, immature red blood cells. Progression of such an anemia leads to a decreased oxygen carrying capacity of the blood and may ultimately result in symptoms of fatigue, weakness, and shortness of breath. Other complaints can be an inflamed tongue, nerve tingling, diarrhea, depression and irritability, graying hair, impaired wound healing.

d. Adequate intake: 400 mcg/day

e. When deficient: Deficiency during pregnancy can cause neural tube defects, Megalocytic anemia

f. Sources: Green leafy vegetables (foliage) are rich sources of folate and provide the basis for its name. Citrus fruit juices, legumes, tree nuts, bananas, meat and fortified cereals are also excellent sources of folate

g. Use in treatment and prevention: It is widely known that the use of folic acid reduces materno-fetal complications, birth defects and neural tube defects. In cancer research, folic acid supplements may help people with cancers of the cervix, colon and rectum, lung, esophagus, brain, pancreas, and breast.

h. Toxicity: No adverse effects have been associated with the consumption of excess folate from foods.

VITAMIN B12: Cyanocobalamin, hydroxycobalamin, methylcobalamin

a. Water Soluble

b. Main actions: Vitamin B12 has the largest and most complex chemical structure of all the vitamins. B12 in addition to folate are crucial in the synthesis of aminoacids that are needed for proper DNA and RNA function. It is vital for normal nerve activity, the production of healthy white and red blood cells as well as platelets. Aids in metabolism, of proteins, fats and carbohydrates.

c. Unique property: Absorption of vitamin B12 from food requires normal function of the stomach, pancreas, and small intestine. Stomach acid and enzymes free vitamin B12 from food, allowing it to bind to other proteins called R proteins. In the alkaline environment of the small intestine, R proteins are degraded by pancreatic enzymes, freeing vitamin B12 to bind to intrinsic factor (IF), a protein secreted by specialized cells in the stomach. Receptors on the surface of the small intestine take up the IF-B12 complex only in the presence of calcium, which is supplied by the pancreas. Vitamin B12 can also be absorbed by passive diffusion, but this process is very inefficient—only about 1% absorption of the vitamin B12 dose is absorbed passively. This complexity is a basis for a high risk of deficiency states. Atrophic gastritis is thought to affect 10%-30% of people over 60 years of age, and the condition is frequently associated with infection by the bacteria, Helicobacter pylori. H. pylori infection induces chronic inflammation of the stomach, which may progress to peptic ulcer disease, atrophic gastritis, and/or gastric cancer in some individuals. This too may interfere with the absorption of vitamin B12. Lastly, gastric bypass surgery can cause significant B12 deficiency.

d. Adequate intake: 2.4 mcg/day

e. When deficient: Vitamin B12 deficiency is estimated to affect 10%-15% of individuals over the age of 60. The most common causes of vitamin B12 deficiency are: 1) an autoimmune condition known as pernicious anemia and 2) food-bound vitamin B12 malabsorption. Yet, Individuals with mild vitamin B12 deficiency may not experience symptoms. The initial complaints are lack of centration, and fatigue. In more severe cases tongue soreness, appetite loss, and constipation as well as numbness and tingling of the arms and legs, difficulty walking, memory loss, disorientation, and dementia with or without mood changes. The disease state caused by vitamin B12 deficiency is Megaloblastic anemia

f. Sources: Animal products such as meat, poultry, fish, shellfish, raw egg yolk, liver, and in small amounts in peanuts, Leafy vegetables, pasta, bread, and fortified cereal

g. Use in treatment and prevention: Vitamin B12 is commonly used to prevent neural tube defects in pregnant women, treat chronic fatigue syndrome, help with depression, chronic fatigue, decreased concentration, and prevent cardiovascular disease, prevent breast cancer, Alzheimer’s disease and dementia.

h. Toxicity: No toxic or adverse effects have been associated with large intakes of vitamin B12 from food or supplements in healthy people.

VITAMIN C: Ascorbic acid

a. Water Soluble

b. Main Actions: Vitamin C is required for the synthesis of collagen, an important structural component of blood vessels, tendons, ligaments, and bone. Vitamin C also plays an important role in the synthesis of the neurotransmitter critical to brain function and mood, norepinephrine. It also assists in the transport of fat and mitochondrial health, and in the metabolism of cholesterol to bile acids. It is also known for its potent antioxidant abilities and the prevention of damage induced by free radicals.

c. Adequate intake: 90-125 mg/day. Smokers need almost three times the normal dose.

d. When deficient: Scurvy

e. Sources: Many citrus fruits and vegetables, rose hips, strawberries, blueberries, liver, five servings (2½ cups) of fruits and vegetables should average out to about 200 mg of vitamin C. Vitamin C is easily destroyed with cooking.

f. Use in prevention: Use of vitamin C may aid the immune system, aid in the prevention of cataracts, reduce blood pressure, and help prevent coronary artery disease and stroke. Its use is associated with a decreased incidence of cancers of the mouth, throat and vocal chords, esophagus, stomach, colon-rectum, and lung. Use can also decrease levels of uric acid and gout as well as decrease lead levels in the body.

g. Toxicity: Very large doses of vitamin C can cause erosion of dental enamel, kidney stones, excess iron absorption, vitamin B12 deficiency and increased oxidative stress.

VITAMIN D: Vitamin D3 is cholecalciferol (synthesized in the body) and Vitamin D2 is ergocalciferol (plant origin).

Vitamin D itself is biologically inactive, and it must be metabolized to its biologically active forms. After it is consumed in the diet or synthesized in the skin, vitamin D enters the blood and is transported to the liver. There it is converted into calcidiol – 25 vitamin D. Calcidiol then is transported to the kidney where it becomes the most potent and activated form of vitamin D: 1 alpha,25-dihydroxyvitamin D: calcitriol.

a. Fat soluble

b. Main actions: Vitamin D is essential for the balance of calcium in the blood stream, bone health, muscle health, cell maturity, immune health, insulin release, and blood pressure regulation.

c. Adequate intake: 600-5000 IU/day

d. When deficient: People usually feel muscle weakness, fatigue, chronic pain, depression, Severe deficiency in children is called ‘rickets’ and in adults it is called ‘osteomalacia’

e. Sources: Vitamin D3 can be synthesized by humans in the skin upon exposure to ultraviolet-B (UVB) radiation from sunlight, or it can be obtained from the diet. Fish, eggs, liver, mushrooms. Plants synthesize ergosterol, which is converted to vitamin D2 (ergocalciferol) by ultraviolet light. Dietary sources include fatty fish (mackerel, salmon, and sardines), fish liver oils, and eggs from hens that have been fed vitamin D.

f. Use in treatment and prevention: It has been suggested that the use of vitamin D prevents osteoporosis, and in the prevention of malignant tumors that are known to have vitamin D receptors (VDR), including breast, lung, skin (melanoma), colon, and bone as it promotes cell differentiation. It is important to note that epidemiological studies cannot prove such associations.

g. Toxicity: Vitamin D toxicity is very unlikely in healthy people at intake levels lower than 10,000 IU/day. Toxicity is associated with abnormally high calcium levels in the blood which could result in kidney stones, and calcification of organs like the heart and kidneys if untreated over a long period of time

VITAMIN E: Tocopherols, tocotrienols

a. Fat soluble

b. Main actions: The main function of vitamin E is to be an antioxidant. Vitamin E’s main role is to intercept free radicals and thus prevent a chain reaction of lipid destruction, maintain cell membranes and aid in the disposal of oxidized LDL cholesterol. Vitamin E helps the immune system and also is known to be a blood thinner as it prevents platelets from sticking together. It also helps prevent cataracts.

c. Adequate intake: 15 mg or 22.5 IU/day

d. When deficient: Severe vitamin E deficiency may result in neurological symptoms, including impaired balance and coordination (ataxia), injury to the sensory nerves (peripheral neuropathy), muscle weakness (myopathy), and damage to the retina of the eye (pigmented retinopathy).

e. Sources: Major sources of vitamin E include vegetable oils (olive, sunflower, and safflower oils), nuts, whole grains, and green leafy vegetables.

f. Use in treatment and prevention: Vitamin E has been studied for the prevention of heart disease, reduce the harmful effects of diabetes and hyperglycemia, reduce the risk of dementia, and cancer as vitamin E can inhibit proliferation and induce apoptosis in a number of cancer cell lines.

g. Toxicity: Although there are no known clear toxic effects, the most worrisome possibility is that of impaired blood clotting, which may increase the likelihood of bleeding in some individuals.

VITAMIN K: phylloquinone, menaquinones

a. Fat soluble

b. Main actions: Clotting, bone mineralization and cell growth

c. Adequate intake: 90 – 120 mcg/day

d. When deficient a person may feel symptoms that include easy bruising and bleeding that may be manifested as nosebleeds, bleeding gums, blood in the urine, blood in the stool, tarry black stools, or extremely heavy menstrual bleeding.

e. Sources: Bacteria that normally colonize the large intestine synthesize menaquinones (vitamin K2), which are an active form of vitamin K. Phylloquinone (vitamin K1) is the major dietary form of vitamin K. Green leafy vegetables and some vegetable oils (soybean, cottonseed, canola, and olive) are major contributors of dietary vitamin K.

f. Use in treatment and prevention: Vitamin K aids in the prevention of osteoporosis and osteoporotic fractures

g. Toxicity: Although allergic reaction is possible, there is no known toxicity associated with high doses of the phylloquinone (vitamin K1) or menaquinone (vitamin K2) forms of vitamin K

With this I conclude my blog, and hope that I have provided you with a nice summary of the different vitamins out there. I would like to bring it to your attention given the increased use of vitamins in health care today. Being an informed consumer will allow you to have a closer conversation with your doctor and your body with the hopes that you will live a healthy, happy and prosperous life….

Margarita Ochoa-Maya, MD


  1. This is very great thing you have shared with us. Now I found enough resources by your tips about this issue, Thank you.

  2. Thank you. Very helpful for my Biochemistry assignment