Nutrients essential vitamins

Antibiotics (qv) have been fed at subtherapeutic levels to promote mminant animal growth. Possible reasons for the observed growth include decreased activity of microbes having a pathogenic effect on the animal, decreased production of microbial toxins, decreased microbial destmction of essential nutrients, increased vitamin synthesis or synthesis of other growth factors, and increased nutrient absorption because of a thinner intestinal wall... 

Polymeric formulas typically have low osmolality of 300 to 500 mOsm/kg. These formulas also usually supply essential vitamins and minerals in amounts similar to the Adequate Intakes or Recommended Dietary Allowances for these nutrients when the formula is delivered in amounts adequate to meet the macronutrient requirements of most patients. Many polymeric formulas are inexpensive relative to oligomeric formulas. Most polymeric formulas are lactose-free and gluten-free, as are most modern tube feeding products. Products designed to be used as oral supplements generally are polymeric and often have sucrose or other simple sugars added to improve taste. 

Hematopoiesis, the production from undifferentiated stem cells of circulating erythrocytes, platelets, and leukocytes, is a remarkable process that produces over 200 billion new blood cells per day in the normal person and even greater numbers of cells in people with conditions that cause loss or destruction of blood cells. The hematopoietic machinery resides primarily in the bone marrow in adults and requires a constant supply of three essential nutrients—iron, vitamin B12,... 

Plants are significant to the diet of humans and animals since they provide most of the essential nutrients and vitamins. Vitamins C (ascorbic acid), E (a-tocopherol) and K (phylloquinone) are biosynthesized by plants, while (3-carotene, the precursor of vitamin A and ergosterol, the precursor of vitamin D, are also secondary plant metabolites. These metabolites are used in folk medicine and for industrial purposes, as raw materials for pharmaceutical and other products [3]. On the other hand, plants may produce substances, which are toxic and/or irritant to man. 

These nutrients help your body absorb and use food. They also influence gland secretion and maintain a proper balance in your body s chemistry. Fruits, vegetables, meats, dairy products, and whole grain or enriched breads and cereals supply you with essential vitamins and minerals. If you eat a balanced diet containing a variety of fresh and unprocessed food, you probably don t need extra vitamins or minerals. However, if you are neglecting a portion of your diet, see your doctor about a supplement. 

Selenium Some people supplement their diet with tablets that contain essential vitamins and minerals. These supplements may include a small amount of sodium selenate. Selenium also can be found in such foods as fish, eggs, and grains. Selenium works with vitamin E to prevent cell damage. It may help to inhibit the growth of cancer cells. However, in the case of nutrients, more is not always better. The locoweed plant shown in Figure 7-18 provides an example of this principle related to selenium. When a locoweed plant absorbs selenium from the soil, the concentration of selenium increases to a toxic level. Grazing animals that feed on locoweed can become quite ill. 

Figs are a convenient single-food source broad in nutrient content, having exceptional amounts of insoluble and prebiotic dietary fiber, essential dietary minerals, and an unsaturated omega-6 fat, linoleic acid. Essential vitamins A (from carotenoids), B, and K are also present in high densities in the fig. These vitamins have an array of uses in the body—from antioxidant and metabolic roles to participation in blood coagulation and vascular function—that together support cardiovascular health. 

Scurvy is now a preventable disease. In the recent past, it became possible to achieve such a practical result best by studying the principles of the problem. The nutritional science of the early twentieth century provided this basis in principle, and the nutritional problem is now essentially solved. An essential nutrient called vitamin C is ascorbic acid. We have amassed a wealth of information about its chemistry, occurrence, the requirements for it, and the deficiency state produced by its lack. 

A few years ago, industry started the age of engineered functional food. Numerous examples such as the generation of golden rice, the production of healthy plant oils, and engineered plants with increased levels of essential vitamins and nutrients [112] have been published (Table 2). Golden rice was engineered with two... 

Most fruits and vegetables contain more than 80% water and are therefore highly perishable. Water loss and decay account for most of their losses, which are estimated to be more than 30%-40% in the developing countries in the tropics and subtropics [1] due to inadequate handling, transportation, and storage facilities. Apart from physical and economic losses, serious losses do occur in the availability of essential nutrients, notably vitamins and minerals. 

There are 13 vitamins known to be Important In human nutrition. Included In this class of essential nutrients are vitamin A, B-complex (actually composed of a group of 8 vitamins), vitamin C, vitamin D, vitamin E, and vitamin K. We can subdivide vitamins Into 1) the lipid (fat)-soluble compounds (vitamins A, D, E, and K), meaning they dissolve readily In fat and 2) the water-soluble compounds, vitamin B-complex (thiamin, riboflavin, niacin, vitamin B, panthothenlc acid, vitamin B] 2> biotin, and folic acid) and vitamin C, which dissolves readily In aqueous solutions. It has been three decades since the last vitamin (B] 2) discovered In 1948 and as stated by Herbert (1980), It Is probable that no new vitamins will be found. There are substances which are growth factors for other forms of life, such as bacteria, but not for humans. Para-amlnobenzolc acid (PABA), bioflavonoids (vitamin P), choline. Inositol, llpolc acid, and ubiquinone are just a few of these examples. 

All higher animals and many microorganisms lack the biochemical ability to synthesize certain essential organic compounds. These essential nutrients include vitamins, certain amino acids, unsaturated carboxylic acids, purines, and pyrimidines. The aromatic amine p-aminobenzoic acid is an essential nutrient for those bacteria that are sensitive to sulfanilamide therapy. Enzymes within these bacteria use p-aminobenzoic acid to synthesize another essential compound called folic acid ... 

Also see DISEASES, section headed "Essential Nutrients" and VITAMIN [S].)... 

Amounts of essential nutrients, along with the requirements, must be listed. Every label must list total grams or milligrams, along with required amounts, of fat, saturated fat, cholesterol, sodium, total carbohydrates (sugar and dietary fiber), protein, and essential vitamins and minerals. 

The multielement analysis of hair samples can help determine whether a person is lacking in essential vitamins and nutrients. ... 

Deficiency of essential nutrients or vitamins can directly cause toxic effects. For example, lack of enough Vitamin A reduces the ability of the MFO enzyme system to metabolize chemicals, which has the effect of making most chemicals more toxic. Lack of available cofactors that are necessary in order for some metabolic reactions to occur could also limit the amount of metabolic detoxification. This could also result from a low protein diet. Also, poor nutrition (for example, starvation) might lead to mobilization of fat, which could release stored amounts of chemicals and lead to toxic effects. 

Because of the simplicity of swiae and poultry feeds, most feed manufacturers add vitamins (qv) and trace minerals to ensure an adequate supply of essential nutrients. Amino acids (qv) such as methionine [7005-18-7] lysiae [56-87-17, threonine [36676-50-3] and tryptophan [6912-86-3], produced by chemical synthesis or by fermentation (qv), are used to fortify swiae and poultry diets. The use of these supplements to provide the essential amino acids permits diets with lower total cmde proteia coateat. 

The American Dietetic Association, the American Heart Association, and the National Heart, Lung and Blood Institute recommend 142—198 g (5—7 02) of lean, trimmed meat daily. It was also pointed out that trimmed meat, especially red meat, provides large amounts of essential nutrients such as iron, 2inc, vitamin balanced protein. The idea that the risk of CHD and cancer can be greatiy reduced by avoiding a meat-centered diet have prompted... 

The elemental and vitamin compositions of some representative yeasts are Hsted in Table 1. The principal carbon and energy sources for yeasts are carbohydrates (usually sugars), alcohols, and organic acids, as weU as a few other specific hydrocarbons. Nitrogen is usually suppHed as ammonia, urea, amino acids or oligopeptides. The main essential mineral elements are phosphoms (suppHed as phosphoric acid), and potassium, with smaller amounts of magnesium and trace amounts of copper, zinc, and iron. These requirements are characteristic of all yeasts. The vitamin requirements, however, differ among species. Eor laboratory and many industrial cultures, a commercial yeast extract contains all the required nutrients (see also Mineral nutrients). 

Cobalt is one of twenty-seven known elements essential to humans (28) (see Mineral NUTRIENTS). It is an integral part of the cyanocobalamin [68-19-9] molecule, ie, vitamin B 2> only documented biochemically active cobalt component in humans (29,30) (see Vitamins, VITAMIN Vitamin B 2 is not synthesized by animals or higher plants, rather the primary source is bacterial flora in the digestive system of sheep and cattle (8). Except for humans, nonmminants do not appear to requite cobalt. Humans have between 2 and 5 mg of vitamin B22, and deficiency results in the development of pernicious anemia. The wasting disease in sheep and cattle is known as bush sickness in New Zealand, salt sickness in Florida, pine sickness in Scotland, and coast disease in AustraUa. These are essentially the same symptomatically, and are caused by cobalt deficiency. Symptoms include initial lack of appetite followed by scaliness of skin, lack of coordination, loss of flesh, pale mucous membranes, and retarded growth. The total laboratory synthesis of vitamin B 2 was completed in 65—70 steps over a period of eleven years (31). The complex stmcture was reported by Dorothy Crowfoot-Hodgkin in 1961 (32) for which she was awarded a Nobel prize in 1964. 

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