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VITAMIN
The discovery of the vitamins was a major scientific achievement in our understanding of health and disease. In 1912, Casimir Funk originally coined the term "vitamine" A vitamin is an organic molecule (or related set of molecules) that is an essential micronutrient which an organism needs in small quantities for the proper functioning of its metabolism. Essential nutrients cannot be synthesized in the organism, either at all or not in sufficient quantities, and therefore must be obtained through the diet. Vitamin C can be synthesized by some species but not by others; it is not a vitamin in the first instance but is in the second. The term vitamin does not include the three other groups of essential nutrients: minerals, essential fatty acids, and essential amino acids. Most vitamins are not single molecules, but groups of related molecules called vitamers. For example, vitamin E consists of four tocopherols and four tocotrienols. The thirteen vitamins required by human metabolism are vitamin A (as all- trans - retinol, all- trans -retinyl-esters, as well as all- trans - beta-carotene and other provitamin A carotenoids), vitamin B 1 (thiamine), vitamin B 2 (riboflavin), vitamin B 3 (niacin), vitamin B 5 (pantothenic acid), vitamin B 6 (pyridoxine), vitamin B 7 (biotin), vitamin B 9 (folic acid or folate), vitamin B 12 (cobalamins), vitamin C (ascorbic acid), vitamin D (calciferols), vitamin E (tocopherols and tocotrienols), and vitamin K (quinones). Vitamins have diverse biochemical functions. Vitamin A acts as a regulator of cell and tissue growth and differentiation. Vitamin D provides a hormone-like function, regulating mineral metabolism for bones and other organs. The B complex vitamins function as enzyme cofactors (coenzymes) or the precursors for them. Vitamins C and E function as antioxidants. Both deficient and excess intake of a vitamin can potentially cause clinically significant illness, although excess intake of water-soluble vitamins is less likely to do so.
Before 1935, the only source of vitamins was from food. If intake of vitamins was lacking, the result was vitamin deficiency and consequent deficiency diseases. Then, commercially produced tablets of yeast-extract vitamin B complex and semi-synthetic vitamin C became available. This was followed in the 1950s by the mass production and marketing of vitamin supplements, including multivitamins, to prevent vitamin deficiencies in the general population. Governments mandated addition of vitamins to staple foods such as flour or milk, referred to as food fortification, to prevent deficiencies. Recommendations for folic acid supplementation during pregnancy reduced risk of infant neural tube defects. The term vitamin is derived from the word vitamine , which was coined in 1912 by Polish biochemist Casimir Funk, who isolated a complex of micronutrients essential to life, all of which he presumed to be amines. When this presumption was later determined not to be true, the "e" was dropped from the name. All vitamins were discovered (identified) between 1913 and 1948. 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, to the degree that urinary output is a strong predictor of vitamin consumption. Because they are not as readily stored, more consistent intake is important. Fat-soluble vitamins are absorbed through the intestinal tract with the help of lipids (fats). Vitamins A and D can accumulate in the body, which can result in dangerous hypervitaminosis. Fat-soluble vitamin deficiency due to malabsorption is of particular significance in cystic fibrosis. Anti-vitamins Anti-vitamins are chemical compounds that inhibit the absorption or actions of vitamins. For example, avidin is a protein in raw egg whites that inhibits the absorption of biotin; it is deactivated by cooking. Pyrithiamine, a synthetic compound, has a molecular structure similar to thiamine, vitamin B 1 , and inhibits the enzymes that use thiamine. Biochemical functions Each vitamin is typically used in multiple reactions, and therefore most have multiple functions.[24]
Deficient intake Vitamin deficiency The body's stores for different vitamins vary widely; vitamins A, D, and B 12 are stored in significant amounts, mainly in the liver, and an adult's diet may be deficient in vitamins A and D for many months and B 12 in some cases for years, before developing a deficiency condition. However, vitamin B 3 (niacin and niacinamide) is not stored in significant amounts, so stores may last only a couple of weeks. For vitamin C, the first symptoms of scurvy in experimental studies of complete vitamin C deprivation in humans have varied widely, from a month to more than six months, depending on previous dietary history that determined body stores. Deficiencies of vitamins are classified as either primary or secondary. A primary deficiency occurs when an organism does not get enough of the vitamin in its food. A secondary deficiency may be due to an underlying disorder that prevents or limits the absorption or use of the vitamin, due to a "lifestyle factor", 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, but may be consuming less than the recommended amounts; a national food and supplement survey conducted in the US over 2003-2006 reported that over 90% of individuals who did not consume vitamin supplements were found to have inadequate levels of some of the essential vitamins, notably vitamins D and E. Well-researched human vitamin deficiencies involve thiamine (beriberi), niacin (pellagra), vitamin C (scurvy), folate (neural tube defects) and vitamin D (rickets). In much of the developed world these deficiencies are rare due to an adequate supply of food and the addition of vitamins to common foods. In addition to these classical vitamin deficiency diseases, some evidence has also suggested links between vitamin deficiency and a number of different disorders. Excess intake Some vitamins have documented acute or chronic toxicity at larger intakes, which is referred to as hypertoxicity. The European Union and the governments of several countries have established Tolerable upper intake levels (ULs) for those vitamins which have
documented toxicity (see table). The likelihood of consuming too much of any vitamin from food is remote, but excessive intake (vitamin poisoning) from dietary supplements does occur. In 2016, overdose exposure to all formulations of vitamins and multi- vitamin/mineral formulations was reported by 63,931 individuals to the American Association of Poison Control Centers with 72% of these exposures in children under the age of five. In the US, analysis of a national diet and supplement survey reported that about 7% of adult supplement users exceeded the UL for folate and 5% of those older than age 50 years exceeded the UL for vitamin A. Name of the vitamin Chemical name solubility US^ Recommende d dietary allowances (male/female, age 19–70) Deficiency disease Overdose syndrome/symptom s Food sources Vitamin A all- trans - Retinol, Retinals, and alternative provitamin A- functioning Carotenoids including all- trans - beta-carotene fat 900 μg/700^ μg^ Night blindness,^ hyperkeratosis, and keratomalacia Hypervitaminosis A from animal origin as Vitamin A / all- trans -Retinol: Fish in general, liver and dairy products; from plant origin as provitamin A / all- trans -beta-carotene: orange, ripe yellow fruits, leafy vegetables, carrots, pumpkin, squash, spinach; Vitamin B 1 Thiamine Water 1.2 mg/1.1 mg Beriberi, Wernicke-Korsakoff syndrome Drowsiness and muscle relaxation[10] Pork, wholemeal grains, brown rice, vegetables, potatoes, liver, eggs Vitamin B 2 Riboflavin Water 1.3 mg/1.1 mg Ariboflavinosis, glossitis, angular stomatitis Dairy products, bananas, green beans, asparagus Vitamin B 3 Niacin, Niacinamide, Nicotinami de riboside Water 16 mg/14 mg Pellagra Liver damage (doses
2g/day)[11]^ and other problems Meat, fish, eggs, many vegetables, mushrooms, tree nuts Vitamin B 5 Pantothenic acid Water 5 mg/5 mg Paresthesia Diarrhea; possibly nausea and heartburn Meat, broccoli, avocados Vitamin B 6 Pyridoxine, Pyridoxamine, Pyrid Water 1.3–1.7 mg/1.2– Anemia,[13]^ Peripheral neuropathy Impairment Meat, vegetables, tree nuts, bananas
infants[15]^ congestive heart failure.[16][17] seeds, and seed oils Vitamin K Phylloquinone, Menaquinones Fat AI: 110 μg/120 μg Bleeding diathesis Decreased anticoagulation effect of warfarin.[18] Leafy green vegetables such as spinach; egg yolks; liver
Vitamin B17 (Laetrile or Amygdalin):
Laetrile is often wrongly called amygdalin or vitamin B17. Rather, it is a drug that contains purified amygdalin — a compound found in the seeds or kernels of many fruits, raw nuts, beans and other plant foods.Laetrile is best known as a controversial treatment for cancer.
What Is Laetrile?
Share on Pinterest Laetrile is the name of a drug created in 1952 by Dr. Ernst T. Krebs, Jr. It contains purified amygdalin, which is a compound found naturally in the following Raw nuts: Such as bitter almonds, raw almonds and macadamia nuts. ● Vegetables: Carrots, celery, bean sprouts, mung beans, lima beans and butter beans.
● Seeds: Millet, flaxseeds and buckwheat. ● Pits of : Apples, plums, apricots, cherries and pears. You can take laetrile as a pill or receive it as an injection into the veins or muscles It is a controversial cancer treatment that was popular in the 1970s. However, it was banned in many US states after research deemed it ineffective and potentially poisonous. When laetrile passes through the body, it is converted into hydrogen cyanide — a compound that can prevent cells from using oxygen and eventually kill them. Some theories suggest that hydrogen cyanide may have anticancer effects. Yet, these theories don’t have much evidence to support their claims. Interestingly, there is some evidence that laetrile may provide health benefits. Studies have found that it may help reduce blood pressure, relieve pain and boost immunity.
