However, some people may need supplements to correct vitamin or mineral deficiencies and this includes:. Women who are pregnant or planning a pregnancy are recommended folic acid also known as folate supplements to reduce their risk of having a child with a neural tube defect, such as spina bifida.
Folic acid is a B-group vitamin which can also be found in some fortified foods such as breads and breakfast cereals. Foods fortified with folic acid have the nutrient added to them during production to boost their nutritional value. Also, people who follow vegan diets, especially if pregnant, may benefit from vitamin B12 supplements.
It is commonly believed that taking mega-doses of certain vitamins will act like medicine to cure or prevent certain ailments. For instance, vitamin C is suggested as a cure for the common cold, and vitamin E is widely promoted as a beneficial antioxidant to help prevent heart disease. After extensive research, however, neither of these claims has been shown to be true. Large-scale studies have consistently shown little benefit in taking mega-doses of supplements.
In fact, there is some evidence that taking high-dose supplements to prevent or cure major chronic diseases such as heart disease and cancer , may be harmful to your health. Vitamin supplements are commonly considered to be an antidote to stress. Popping a pill will not likely cure persistent tiredness either. If you are feeling run down, it is more likely to be due to stress, depression, insufficient sleep or other factors, rather than a vitamin deficiency.
If you feel like this regularly, seek medical advice. Vitamin E is often singled out as the potential fountain of youth. However, there is no evidence that taking large doses of any vitamin can stall or reverse the effects of ageing. Neither can one vitamin restore a flagging sex drive or cure infertility. Some claims have been made that certain vitamins can treat different cancers.
However, research shows this is not the case. For example:. Proper balance and adequate levels of essential nutrients is important for a range of complex processes in our body.
When vitamins are taken as supplements, they are introduced into the body at levels that could never be achieved by eating even the healthiest of diets. For instance, provitamin A beta-carotene in food is accompanied by hundreds of its carotenoid relatives. Simply taking a vitamin pill is not an instant fix for feeling run down or lacking in energy.
When you artificially remove one of them and provide it completely out of context, it may not be as effective and, in the case of some vitamins, can have negative effects. Vitamins and mineral supplements can also interfere with prescription medicines and medical treatments. In extreme cases, for example, where people take times the recommended dietary intake RDI , this can stop the work of anticonvulsant drugs, such as those used in epilepsy.
Many people mistakenly believe that since small amounts of vitamins are good for you, then large amounts must be better.
For a healthy adult, if supplements are used, they should generally be taken at levels close to the RDI. Taking vitamin and mineral supplements is a short-term measure. The long-term use of some high-dose supplements can lead to symptoms of toxicity. If you feel that you could be lacking in certain vitamins and minerals, it may be better to look at changing your diet and lifestyle rather than reaching for supplements.
If you need help, see your doctor or a dietitian. Some complementary medicines , such as vitamin and mineral supplements can interact with prescription medicines and medical treatments. If you are advised to take vitamin supplements, it is a good idea to see a dietitian , who can work with your doctor or other health professionals to provide dietary advice related to your situation. And if you do need to take a supplement, it is best to take multivitamins at the recommended dietary level, rather than single nutrient supplements or high-dose multivitamins.
Remember, to report any complementary medicines including vitamin and mineral supplements you are taking when you visit any healthcare professional. This page has been produced in consultation with and approved by:. The size of a standard drink can vary according to the type of alcohol. The Alexander technique stresses that movement should be economical and needs only the minimum amount of energy and effort. A common misconception is that anorexia nervosa only affects young women, but it affects males and females of all ages.
At high enough dosages, some vitamins cause side-effects such as nausea, diarrhea, and vomiting. The doses of vitamins differ because individual tolerances can vary widely and appear to be related to age and state of health. Vitamins are classified as either water-soluble or fat-soluble. Water-soluble vitamins dissolve easily in water and, in general, are readily excreted from the body, to the degree that urinary output is a strong predictor of vitamin consumption.
Because they are more likely to accumulate in the body, they are more likely to lead to hypervitaminosis than are water-soluble vitamins.
Fat-soluble vitamin regulation is of particular significance in cystic fibrosis. The value of eating a certain food to maintain health was recognized long before vitamins were identified. The ancient Egyptians knew that feeding liver to a person would help cure night blindness, an illness now known to be caused by a vitamin A deficiency.
In , the Scottish surgeon James Lind discovered that citrus foods helped prevent scurvy, a particularly deadly disease in which collagen is not properly formed, causing poor wound healing, bleeding of the gums, severe pain, and death.
This led to the nickname limey for British sailors. Lind's discovery, however, was not widely accepted by individuals in the Royal Navy's Arctic expeditions in the 19th century, where it was widely believed that scurvy could be prevented by practicing good hygiene, regular exercise, and maintaining the morale of the crew while on board, rather than by a diet of fresh food. In the early 20th century, when Robert Falcon Scott made his two expeditions to the Antarctic, the prevailing medical theory at the time was that scurvy was caused by "tainted" canned food.
During the late 18th and early 19th centuries, the use of deprivation studies allowed scientists to isolate and identify a number of vitamins. Lipid from fish oil was used to cure rickets in rats, and the fat-soluble nutrient was called "antirachitic A".
Thus, the first "vitamin" bioactivity ever isolated, which cured rickets, was initially called "vitamin A"; however, the bioactivity of this compound is now called vitamin D. The mice that received only the individual constituents died, while the mice fed by milk itself developed normally. He made a conclusion that "a natural food such as milk must therefore contain, besides these known principal ingredients, small quantities of unknown substances essential to life.
In East Asia, where polished white rice was the common staple food of the middle class, beriberi resulting from lack of vitamin B1 was endemic. In , Takaki Kanehiro, a British trained medical doctor of the Imperial Japanese Navy, observed that beriberi was endemic among low-ranking crew who often ate nothing but rice, but not among officers who consumed a Western-style diet. With the support of the Japanese navy, he experimented using crews of two battleships; one crew was fed only white rice, while the other was fed a diet of meat, fish, barley, rice, and beans.
The group that ate only white rice documented crew members with beriberi and 25 deaths, while the latter group had only 14 cases of beriberi and no deaths. This convinced Takaki and the Japanese Navy that diet was the cause of beriberi, but they mistakenly believed that sufficient amounts of protein prevented it. In , the first vitamin complex was isolated by Japanese scientist Umetaro Suzuki, who succeeded in extracting a water-soluble complex of micronutrients from rice bran and named it aberic acid later Orizanin.
He published this discovery in a Japanese scientific journal. In Polish-born biochemist Casimir Funk, working in London, isolated the same complex of micronutrients and proposed the complex be named "vitamine".
It was later to be known as vitamin B3 niacin , though he described it as "anti-beri-beri-factor" which would today be called thiamine or vitamin B1. Funk proposed the hypothesis that other diseases, such as rickets, pellagra, coeliac disease, and scurvy could also be cured by vitamins. Max Nierenstein a friend and reader of Biochemistry at Bristol University reportedly suggested the "vitamine" name from "vital amine". In , Jack Cecil Drummond proposed that the final "e" be dropped to deemphasize the "amine" reference, after researchers began to suspect that not all "vitamines" in particular, vitamin A have an amine component.
In , Paul Karrer elucidated the correct structure for beta-carotene, the main precursor of vitamin A, and identified other carotenoids.
For their investigations on carotenoids, flavins and vitamins A and B2, they both received the Nobel Prize in Chemistry in In , George Wald was awarded the Nobel Prize along with Ragnar Granit and Haldan Keffer Hartline for his discovery that vitamin A could participate directly in a physiological process. The term vitamin was derived from "vitamine", a compound word coined in by the Polish biochemist Kazimierz Funk[53] when working at the Lister Institute of Preventive Medicine.
The name is from vital and amine, meaning amine of life, because it was suggested in that the organic micronutrient food factors that prevent beriberi and perhaps other similar dietary-deficiency diseases might be chemical amines. This was true of thiamine, but after it was found that other such micronutrients were not amines the word was shortened to vitamin in English. Once discovered, vitamins were actively promoted in articles and advertisements in McCall's, Good Housekeeping, and other media.
They promoted foods such as yeast cakes, a source of B vitamins, on the basis of scientifically-determined nutritional value, rather than taste or appearance. Yoder is credited with first using the term vitamania, in , to describe the appeal of relying on nutritional supplements rather than on obtaining vitamins from a varied diet of foods. Most countries place dietary supplements in a special category under the general umbrella of foods, not drugs. As a result, the manufacturer, and not the government, has the responsibility of ensuring that its dietary supplement products are safe before they are marketed.
Regulation of supplements varies widely by country. Even though product registration is not required, these regulations mandate production and quality control standards including testing for identity, purity and adulterations for dietary supplements.
Likewise, monographs of the European Pharmacopoeia Ph. The reason that the set of vitamins skips directly from E to K is that the vitamins corresponding to letters F—J were either reclassified over time, discarded as false leads, or renamed because of their relationship to vitamin B, which became a complex of vitamins. The German-speaking scientists who isolated and described vitamin K in addition to naming it as such did so because the vitamin is intimately involved in the coagulation of blood following wounding from the German word Koagulation.
At the time, most but not all of the letters from F through to J were already designated, so the use of the letter K was considered quite reasonable. The table nomenclature of reclassified vitamins lists chemicals that had previously been classified as vitamins, as well as the earlier names of vitamins that later became part of the B-complex.
There are other missing B vitamins which were reclassified or determined not to be vitamins. For example, B9 is folic acid and five of the folates are in the range B11 through B16, forms of other vitamins already discovered, not required as a nutrient by the entire population like B10, PABA for internal use , biologically inactive, toxic, or with unclassifiable effects in humans, or not generally recognised as vitamins by science,[64] such as the highest-numbered, which some naturopath practitioners call B21 and B There are also nine lettered B complex vitamins e.
There are other D vitamins now recognised as other substances,[63] which some sources of the same type number up to D7. The controversial cancer treatment laetrile was at one point lettered as vitamin B There appears to be no consensus on any vitamins Q, R, T, V, W, X, Y or Z, nor are there substances officially designated as Vitamins N or I, although the latter may have been another form of one of the other vitamins or a known and named nutrient of another type.
Anti-vitamins are chemical compounds that inhibit the absorption or actions of vitamins. For example, avidin is a protein in egg whites that inhibits the absorption of biotin. Skills to Develop Define vitamin Know the difference between fat soluble and water soluble vitamins Recognize the names of each of the 13 vitamins For each vitamin, know what the vitamin does and what happens to the human body if: the vitamin is too low in the diet for too long deficiency ; the vitamin is too high in the diet for too long toxicity and be able to list some food sources that are rich in each of the vitamins.
Exercise Please click on the vitamin name below and you will be linked to a Wikipedia article to learn about that vitamin. Health effects Vitamins are essential for the normal growth and development of a multicellular organism. Supplements In those who are otherwise healthy, there is little evidence that supplements have any benefits with respect to cancer or heart disease. Effect of cooking Shown below is percentage loss of vitamins after cooking averaged for common foods such as vegetables, meat or fish.
Children and pregnant women are especially vulnerable to the consequences of iron deficiency 3. Iron deficiency is a leading cause of anemia which is defined as low hemoglobin concentration. Anemia during pregnancy increases the risk of death for the mother and low birth weight for the infant. Worldwide, maternal and neonatal deaths total between 2. Preventing iron deficiency helps improve children's learning ability and cognitive development. Vitamin A Vitamin A supports healthy eyesight and immune system functions.
Children with vitamin A deficiency face an increased risk of blindness and death from infections such as measles and diarrhea 6. Globally, vitamin A deficiency affects an estimated million preschool-age children 6. Providing vitamin A supplements to children ages months is highly effective in reducing deaths from all causes where vitamin A deficiency is a public health concern 6.
Vitamin D Vitamin D builds strong bones by helping the body absorb calcium 7. This helps protect older adults from osteoporosis.
Vitamin D deficiency causes bone diseases, including rickets in children and osteomalacia in adults 7. Vitamin D helps the immune system resist bacteria and virsues 7.
Vitamin D is required for muscle and nerve functions 7. Available data suggest that vitamin D deficiency may be widespread globally 8. Bodies make vitamin D from sunlight, but this varies based on geography, skin color, air pollution, and other factors. Also, sunlight exposure needs to be limited to avoid risk of skin cancer. Globally an estimated 1.
Iodine content in most foods and beverages is low. The amount of iodine added to salt can be adjusted so that people maintain adequate iodine intake even if they consume less salt The American Thyroid Association and the American Academy of Pediatrics recommend that pregnant or breastfeeding women take a supplement every day containing micrograms of iodine. The American Thyroid Association recommends women who are planning a pregnancy consume a daily iodine supplement starting at least 3 months in advance of pregnancy.
Fortifying salt with iodine successfully increases intake of iodine. Folate Folate vitamin B9 is essential in the earliest days of fetal growth for healthy development of the brain and spine Folic acid is another form of vitamin B9. Women of reproductive age need micrograms of folic acid every day Ensuring sufficient levels of folate in women prior to conception can reduce neural tube defects such as spina bifida and anencephaly Providing folic acid supplements to women years and fortifying foods such as wheat flour with folic acid reduces the incidence of neural tube defects and neonatal deaths Folate is especially important before and during pregnancy.
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