Vitamin prevalence

Vitamin D [1406-12-2] is a material that is formed ia the skin of animals upon kradiation by sunlight and serves as a precursor for metaboUtes that control the animal s calcium homeostasis and act ki other hormonal functions. A deficiency of vitamin D can cause rickets, as weU as other disease states. This tendency can be a problem wherever animals, including humans, especially kifants and children, receive an kiadequate amount of sunshine. The latter phenomenon became prevalent with the advent of the kidustrial revolution, and efforts to cute rickets resulted ki the development of commercial sources of vitamin D for supplementation of the diet of Hvestock, pets, and humans. 

Occurrence. The provitamins, precursors of the vitamin Ds, are distributed widely in nature, whereas the vitamins themselves are less prevalent. The amounts of provitamins D2 and D in various plants and animals are Hsted in Table 2. 

Riboflavin was first isolated from whey in 1879 by Blyth, and the structure was determined by Kuhn and coworkers in 1933. For the structure determination, this group isolated 30 mg of pure riboflavin from the whites of about 10,000 eggs. The discovery of the actions of riboflavin in biological systems arose from the work of Otto Warburg in Germany and Hugo Theorell in Sweden, both of whom identified yellow substances bound to a yeast enzyme involved in the oxidation of pyridine nucleotides. Theorell showed that riboflavin 5 -phosphate was the source of the yellow color in this old yellow enzyme. By 1938, Warburg had identified FAD, the second common form of riboflavin, as the coenzyme in D-amino acid oxidase, another yellow protein. Riboflavin deficiencies are not at all common. Humans require only about 2 mg per day, and the vitamin is prevalent in many foods. This vitamin... 

Thorarinsson, R., M.L. Landholt, D.G. Elliott, R.J. Pascho, and R.W. Hardy. 1994. Effect of dietary Vitamin E and selenium on growth, survival and the prevalence of Renibacterium salmoninarium in chinook salmon (Oncorhynchus tshawytscha). Aquaculture 121 343-358. 

Cu + Co deficit Especially in Swamp ecosystems Low content of Cu and Co in Podsoluvisols, Podzols, Arenosols and Histosols. Declining contents of Cu and Co in forage species (Cu from 3 to 0.7 ppm, Co < 5 ppb) Depressed synthesis of BJ2 vitamin and oxidation ferments. Cobalt-deficiency and B12 vitamin-deficiency complicated by Cu deficiency. The prevalent diseases of sheep and cattle... 

In contrast to the dissolution criteria used for water-soluble vitamins, the hierarchy for index minerals is based on their importance in public health. For example, iron was chosen as the number one index mineral because iron deficiency is the most prevalent condition in the United States and because iron is present in almost all the multivitamin-mineral combination products currently available on the... 

The nutritional experiments with carotene and fish oils led to the conclusion that a second fat-soluble compound was essential for normal rat growth. Rickets, the condition caused by vitamin D deficiency, is a disease afflicting children where, because of impaired calcification, bone formation is disturbed and the bones become bowed and otherwise deformed. In adults, especially multiparous women, vitamin D deficiency produced osteomalacia—demineralization of bone, leading to tenderness over the bones, pain, and muscle weakness. Rickets was particularly prevalent in slum areas. Glasgow, Vienna, and Lahore were notorious for the high incidence of the disease. 

Various factors may be associated with variations in calcium needs differences in vitamin D supply, differences in absorption and excretion, differences in activity of the parathyroid glands, differences in steroid hormone production, differences in thyroid function, differences in phosphate supply and utilization. 10 These we will not discuss, although these considerations may make it possible, in individual cases, to circumvent extra needs for calcium by removing the basis for the augmented need. We are here concerned primarily with the fact that individual people, under prevalent conditions, require amounts of calcium which may vary from individual to individual by a factor of 5. 

Osteoporosis, a condition in which bone becomes porous and weak (potentially leading to fractures), is a far more prevalent disease than osteomalacia. While modest levels of serum 25-hydroxyvitamin D will prevent osteomalacia, these levels may not be sufficient to minimize the risk of osteoporosis. Clinical studies have demonstrated that bone mineral density is directly related to serum 25-hydroxyvitamin D levels up to 40 ng/ml. It has also been demonstrated that in elderly women given unusually high doses of calcium and vitamin D3 the risk of both hip and vertebral fractures is substantially reduced. Optimizing bone health in both young and old may require higher levels of vitamin D activity than are typically achieved at recommended doses. This story will play out over time. 

Vitamin A deficiency is worldwide one of the most prevalent nutrition-dependent deficiency diseases. It leads to changes of the respiratory epithelium, which result in repeated infections of the respiratory tract, the main cause of death in vitamin A-deficient children. The difficulty in supplying the respiratory epithelium with vitamin A is that the affected children frequently suffer as well from infections of the gastrointestinal tract with subsequent reduction of the absorption of fat-soluble vitamins. Nutritargeting can in these cases avoid the problems of malabsorption and ensure the micronutrient supply. 

Vitamin B deficiency is a rare condition, but it is prevalent in persons with chronic alcoholism due to low dietary Intake and impaired conversion ofpyridoxine to the active coenzyme pyridoxal phosphate. 

The answer is D. Several vitamin deficiencies can cause anemia due to reduced DNA synthesis in the erythropoietic cells of the bone marrow, especially folic acid and vitamin Bj2 (cobalamin), which are particularly prevalent among elderly patients due to poor diet and reduced absorption. In addition, deficiencies of either folic acid or vitamin Bj2 could produce the megaloblastic anemia seen in this patient. However, the absence of neurologic symptoms, a hallmark of vitamin Bj2 deficiency, makes that diagnosis less likely than folic acid deficiency. 

Inadequate nutrition and conditions which are complicated by malabsorption may lead to thiamine deficiency. Beriberi, a diet-deficiency disease, is especially prevalent in those parts of the East where the diet consists mainly of polished rice. The disease is characterized by neuritis but may also lead to serious heart failure. Recovery is prompt when adequate amounts of vitamin B1 are restored to the diet. Severe deficiency as can occur in alcoholics may lead to Wernicke s encephalopathy, often accompanied by Korsakoff s syndrome. Care should be taken with intravenous substitution with thiamine in these cases to prevent serious complications like vascular collapse with hypotension, respiratory distress or an-gioedema. 

WHO Task Force on Oral Contraceptives. Oral and injectable hormonal contraceptive and signs and symptoms of vitamin deficiency and goitre prevalence studies in five 186. centres in the developing and developed world. WHO... 

Metformin can cause reduced vitamin Bi2 absorption, reducing serum Bi2 concentrations and causing megaloblastic anemia (87), the prevalence of which was 9% in 600 patients with type 2 diabetes taking biguanides (phen-formin or metformin) for a mean of 12 years (88). In 353 patients with type 2 diabetes, treated with insulin, who took metformin for 16 weeks in a placebo-controlled study, metformin increased serum homocysteine concentrations by 4% and reduced serum folate by 7% and vitamin Bi2 by 14% (89). 

Consumers who prefer to self-treat with herbals and/or vitamins appear to be prevalent. 

CCS Case-control 4750 M-F Use of vitamin E and C supplements in combination reduces the prevalence of Alzheimer s disease (208)... 

The richest sources of vitamin C are citrus fruits (e.g., lemon, oranges), tomatoes, potatoes, green chilies, and human milk. Severe deficiency causes scurvy and is prevalent in malnourished infants, children, adults, alcoholics, and drug addicts. Symptoms such as bleeding gums, deformed teeth, brittle bones, impaired wound healing, anemia, and growth retardation are observed. 

Human milk contains about 2 xg/L of vitamin K. Vitamin K denotes a group of compounds containing the 2-methyl-1,4-naphthoquinone chemical moiety. Phylloquinone is the plant form of the vitamin and is the most prevalent homologue in milk. The vitamin is required for the biosynthesis of prothrombin and many other essential blood-clotting factors (Jensen, 1992). 

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