Vitamin B6 Deficiency Essay, Research Paper
Vitamin B6 Deficiency
Main Topic Vitamins and Minerals
A vitamin is any of various fat-soluble or water-soluble organic substances essential in minute amounts for normal growth and activity of the body and obtained naturally from plant and animal foods. A mineral is A naturally occurring, homogeneous inorganic solid substance having a definite chemical composition and characteristic crystalline structure, color, and hardness.
Sub-topic Vitamin B6 Deficiency
Vitamin B6 is used by the body as a catalyst in reactions that involve amino acids. Vitamin B6 deficiency is rare, since most foods eaten contain the vitamin. Vitamin B6 is also called pyridoxine. The definition of pyridoxine is A pyridine derivative, C18H11NO3, occurring especially in cereals, yeast, liver, and fish and serving as a coenzyme in amino acid synthesis. Also called pyridoxine, a cofactor for enzymes. Deficiency leads to inflammation of the skin and mouth, nausea, vomiting, dizziness, weakness and anemia. Vitamin B6 can be helpful in certain patients with nerve conditions, such as carpal tunnel syndrome.
Method of Action
Vitamin B6 is required for normal synthesis of DNA, RNA, and amino acids, and is essential for the proper functioning of more than 60 enzymes. Vitamin B6 activates the release of glycogen from the muscles and liver, and is thus essential for the production of biological energy. Pyridoxine is an important coenzyme in the metabolization of carbohydrates, proteins, and fats. Vitamin B6 is required for the production of hydrochloric acid and magnesium and is essential for absorption of vitamin B12. It also assists in optimizing linoleic acid s functions in the body.
Vitamin B6 is essential in cell replication and for the production of red blood cells and the cells of the immune system. It is crucial for healthy pregnancy and proper functioning of the immune system, red blood cells, mucous membranes, and skin. Because these tissues are composed of rapidly replicating cells they require larger amounts of vitamin B6. It also aids in the utilization of the essential amino acid tryptophan. Pyridoxine assists in maintaining the balance of sodium and potassium, which regulate body fluids and control the nervous and musculoskeletal systems.
Excessive amounts of vitamin B6 are excreted in the urine 8 hours after ingestion, and thus a daily intake of the vitamin along with other members of the B complex is needed. Vitamin B6 is not stored in the liver, but is found exclusively in the muscles.
Vitamin B6 is required in the metabolization of carbohydrate, fats, and proteins and has a primary role in the utilization of proteins and amino acids. Pyridoxine is essential in the conversion of amino acids to carbohydrates or fats for storage or energy, the synthesis of new amino acids from carbohydrates, and the conversion of the amino acid tryptophan to niacin. Vitamin B6 provides a role in the development of most protein-related compounds including hormones, neurotransmitters such as serotonin, hemoglobin in red blood cells, and many enzymes.
Pyridoxine is also necessary in the production of prostaglandins, which are lipid-derived substances that are similar to hormones in that they influence and regulate a wide range of biological processes. Prostaglandins are involved in blood pressure regulation, muscle contraction and heart function. The formation and maintenance of the nervous system and the regulation of mental processes and mood also require the presence of sufficient levels of vitamin B6.
Vitamin B6 is a water-soluble vitamin. The recommended dietary allowance (RDA) for vitamin B6 is 2.0 mg/day for the adult man and 1.6 mg/day for the adult woman. Vitamin B6 in the diet generally occurs as a form called pyridoxal phosphate. In this form, the body cannot absorb it. During the process of digestion, the phosphate group is removed, and pyridoxal is produced. However, the body readily absorbs pyridoxal, and converts it back to the active form of the vitamin (pyridoxal phosphate).
Poultry, fish, liver, and eggs are good sources of vitamin B6, comprising about 3-4 mg vitamin/kg food; meat and milk contain lesser amounts of the vitamin. The vitamin also occurs, at about half this level, in a variety of plant foods, including beans, broccoli, cabbage, and peas. Vitamin B6 tends to be destroyed with prolonged cooking, with storage, or with exposure to light.
As mentioned, vitamin B6 takes various forms. One of these forms, called pyridoxine, is relatively stable. For this reason, pyridoxine is the form of vitamin B6 that is used in vitamin supplements, or when foods are fortified. Apples and other fruits are poor sources of the vitamin, containing only 0.2-0.6 mg vitamin/kg food.
As I also mentioned earlier, vitamin B6 is used mainly in the body for the processing of amino acids, performs this task along with certain enzymes. The enzyme that participates in this type of complex is aminotransferase. Several types of aminotransferase exist. With vitamin B 6 deficiency, while aminotransferase continues to occur in the various organs of the body, there is an abnormally low level of the active vitamin B6/aminotransferase complex present. Thus, this vitamin deficiency results in the impairment of a variety of activities in the body. With supplement correction of the vitamin B6 deficiency, the aminotransferase then readily forms the active complex, and normal metabolism is restored.
Vitamin B6 converts certain amino acids (glutamic acid, aspartic acid, and glycine) to energy. This allows the body to process all dietary protein, even when the dietary protein is in excess of the body’s needs. Vitamin B6 also allows the body to synthesize certain amino acids. For example, if the diet is deficient or low in certain amino acids, such as glycine or serine, vitamin B6 enables the body to make them from sugar. Vitamin B6 is used also for the synthesis of certain hormones, such as adrenaline.
Causes & symptoms
Vitamin B6 deficiency occurs rarely. When it does, it is usually associated with poor absorption of nutrients in the gastrointestinal tract (as in alcoholism, or with chronic diarrhea), the taking of certain drugs that inactivate the vitamin, with genetic disorders that inhibit metabolism of the vitamin, or in cases of starvation.
The symptoms of vitamin B6 deficiency in adults are only vaguely defined. These include nervousness, irritability, insomnia, muscle weakness, and difficulty in walking. Vitamin B6 deficiency may produce fissures and cracking at the corners of the mouth. The deficiency occurred in infants fed early versions of commercial canned infant formula, when the vitamin had been inadvertently omitted from the formula. This error resulted in infants failing to grow, in irritability, and in seizures.
Vitamin B6 status is measured by the transaminase stimulation test. This test requires extraction of red blood cells, and placement of the cells in two test tubes. Special chemicals (reagents) are added to both test tubes to allow for measurement of aminotransferase. This enzyme requires pyridoxal phosphate. A known quantity of pure pyridoxal phosphate is added to one of the test tubes. The activity level of the enzyme is measured, and compared, in both test tubes. If the added pyridoxal phosphate did not stimulate activity, the patient is considered not to be deficient in vitamin B6. Neither is the patient considered deficient if only slight stimulation occurred. But if a stimulation of four-fold or more occurred, a vitamin B6 deficiency is present.
Vitamin B6 deficiency is not a major concern for most people. The deficiency can be prevented with consumption of a mixed diet that includes poultry, fish, eggs, meat, vegetables, and grains.
Susan M. Eng, Independent Distributor
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