Term
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Definition
Vitamin A
Vitamin D
Vitamin E
Vitamin K |
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Term
| Fat soluble vitamins - general information |
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Definition
| Fat-soluble vitamins can be stored. Potential for serious toxicity greatly exceeds that of the water-soluble group. Their absorption requires the presence of bile and pancreatic enzymes. They are transported to the liver via the lymph as a part of lipoproteins. |
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Term
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Definition
Vitamin B1 (thiamine)
Vitamin B2 (riboflavin)
Vitamin B3 (niacin)
Vitamin B6
Folate
Vitamin B12
Pantothenic acid
Biotin
Vitamin C |
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Term
| Water soluble vitamins - general information |
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Definition
| Water-soluble vitamins are stored to a limited extent, and readily excreted in urine, so frequent consumption is necessary to maintain saturation of tissues. |
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Term
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Definition
| Vitamins are substances that must be obtained from dietary sources because they cannot be produced endogenously in sufficient amounts to support basic physiological functions essential for life. |
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Term
| Vitamins - key characteristics |
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Definition
1. Organic compounds that differ from protein, carbohydrates, and fat because they cannot be oxidized to energy.
2. Needs are satisfied by intakes in microgram or milligram amounts.
3. Cannot be endogenously produced, or produced in amounts sufficient to meet needs.
4. Differ in availability depending upon the dietary source.
5. Inadequate intake, impaired absorption, and increased metabolic demand are the most common causes of deficiencies. |
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Term
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Definition
Vitamin A - Diverse actions in cellular regulation and differentiation
Essential role in function of retina
Decreased resistance to infection. |
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Term
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Definition
| fish liver oil, liver, eggs, milk, and dairy products |
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Term
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Definition
| Dark orange vegetables and fruits, dark green and green-leafy vegetables |
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Term
| Symptoms of Vitamin A deficiency |
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Definition
Night blindness
Keratomalacia
Dry scaly skin
Blindness
Depressed immunity
Alopecia |
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Term
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Definition
Calciferol
Calcitriol
Vitamin D3=cholecalciferol (This is the most effective compound for supplementation)
D2=ergocalciferol |
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Term
| Vitamin D - general information |
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Definition
Active metabolite required for calcium absorption from intestine
Prevents rickets in growing children, osteomalacia in adults, and osteoporosis |
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Term
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Definition
| Liver, fatty fish, butter, fortified milk, (exposure of skin to sunlight) |
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Term
| Symptoms of vitamin D deficiency |
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Definition
Rickets
Osteomalacia
Renal Osteodystrophy |
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Term
| Vitamin E - general information |
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Definition
Antioxidant for fatty acids in the cell membranes
Prevents LDL- cholesterol oxidation
Normal immune function |
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Term
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Definition
Vegetable oils, margarine, shortening, nuts, whole grains
Alpha-tocopherol is the most bioactive form |
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Term
| Symptoms of Vitamin E deficiency |
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Definition
| Red Cell hemolysis in malnourished infants |
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Term
| Vitamin K - general information |
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Definition
| Essential for blood clotting, needed for collagen formation |
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Term
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Definition
| Green vegetables, soybean oil, canola oil, and olive oil |
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Term
| Symptoms of Vitamin K deficiency |
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Definition
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Term
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Definition
Needed in metabolizing carbohydrates as food energy source
Prevents beriberi (leg edema, heart failure, mental dementia, GI problems, muscle wasting) |
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Term
| Vitamin B1 - Thiamine food sources |
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Definition
| Whole and enriched grain products, pork, wheat germ |
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Term
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Definition
| Aids in converting carbohydrate, fats, proteins into energy. |
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Term
| Vitamin B2 - Riboflavin food sources |
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Definition
| Milk and milk products, organ meats, eggs, green leafy vegetables, whole and enriched grain products |
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Term
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Definition
| Vital role in metabolism of proteins as a coenzyme |
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Term
| Vitamin B3 - Niacin food sources |
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Definition
Liver, meats, whole and enriched grains, nuts and legumes
Tryptophan is a precursor |
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Term
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Definition
| Coenzyme pyridoxal phosphate. involved in metabolism of amino acids. Meat, liver, whole-grains, soybeans, vegetables. Sideroblastic anemia, Cheilosis or stomatitis. Convulsions. isoniazid therapy is a common cause |
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Term
| Vitamin B12 - Cyanocobalamin |
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Definition
Necessary for the metabolism of methionine, homocysteine, and folic acid
Note: strict vegetarians may be B 12 deficient.
Meat, fish, poultry, eggs, milk and cheese.
Pernicious anemia
Megaloblastic (macrocytic) anemia
Peripheral Neuropathy |
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Term
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Definition
Essential in amino acid metabolism.
Fresh green vegetables, fruits, liver, and yeast.
Homocystinemia
Megaloblastic (macrocytic) anemia
Nueral tube defects |
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Term
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Definition
Important in carbohydrate and fat metabolism.
Organ meats, egg, milk, fish and nuts.
Alopecia, bowel inflammation
Rare: excessive consumption of raw eggwhites (avidin) |
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Term
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Definition
Important component of phospholipids
Affects the mobilization of fat from the liver
Essential in the formation of acetylcholine
Egg yolk, liver, wheat germ, wheat bran, soy beans, milk and peanuts |
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Term
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Definition
Important for collagen synthesis
Promotes activity of aminating enzymes of certain peptide hormones
Potent antioxidant .
Citrus fruits, green vegetables, potatoes, tomatoes, green pepper.
Scurvy |
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Term
| Malabsorption of Vitamins Patients with the following conditions may present with vitamin deficiency due to malabsorption: |
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Definition
| 1. chronic pancreatitis, 2. prolonged diarrhea, 3. hepatobiliary diseases, 4. pernicious anemia, 5. tropical sprue, 6. cystic fibrosis, 7. short bowel syndrome, and, 8. intestinal bypass operations. |
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Term
Vitamin A
Symptoms of toxicity include: |
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Definition
1. Nausea
2. Vomiting
3. Headache
4. Increased cerebrospinal pressure
5. Vertigo
6. Blurred vision
7. Muscular weakness
8. Bulging of the fontanelle (in infants) |
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Term
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Definition
Retinoic Acid
High incidences of spontaneous abortion and birth defects have been observed in pregnant women taking excess retinoic acid for treatment of acne. Retinoids are teratogenic during the first trimester. Birth defects include craniofacial abnormalities, congenital heart disease, and central nervous system disorders. Thus, vitamin A supplementation must be absolutely avoided during pregnancy. |
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Term
Vitamin D
Excess vitamin D causes: |
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Definition
1. Excessive calcification of bone and soft tissues such as the kidney (including kidney stones), lungs, and even the tympanic membrane of the ear, which can result in deafness
2. Headache
3. Weakness
4. Nausea and vomiting
5. Constipation
6. Polyuria and polydipsia
Infants given excessive amounts of vitamin D may have gastrointestinal upsets, bone fragility, retarded growth, and mental retardation. Toxicity should always be monitored when large doses of vitamin D (1000 IU or more) are required for an extended period. |
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Term
| Four of the B vitamins (thiamin, riboflavin, niacin, and pantothenic acid) |
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Definition
| essential to oxidation/reduction reactions from which energy is obtained via glycolysis, the tricarboxylic acid and pentose pathways. |
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Term
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Definition
| Thiamin pyrophosphate, the physiologically active form of thiamin, is a coenzyme in the decarboxylation of alpha-keto acids such as pyruvate and alpha-ketoglutarate metabolism. Syndromes of thiamin deficiency range from beriberi through Wernicke's encephalopathy and Korsakoff's syndrome to alcoholic polyneuropathy. Normal carbohydrate metabolism results in the consumption of thiamin, thus the administration of glucose to marginally malnourished patients can precipitate acute symptoms of thiamin deficiency. In any patient in whom thiamin status may be suspect, such as an alcoholic, 50 to 100 mg of thiamin should be given before or along with dextrose containing fluids. |
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Term
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Definition
| Riboflavin functions in the form of one or the other coenzyme: FMN (flavin mononucleotide) or FAD (flavin adenine dinucleotide). These physiological active forms of the vitamin are involved in the metabolism with the oxidation of glucose and fatty acids and the production of energy or ATP. |
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Term
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Definition
| Nicotinic acid functions in the form of NAD (nicotinamide adenine dinucleotide) or NADP (nicotinamide adenine dinucleotide phosphate). Note that nicotinic acid is not converted to nicotinamide except from the metabolism of NAD. NAD and NADP serve a vital role as coenzymes for a variety of proteins that catalyze oxidation-reduction reactions essential for tissue repair. Niacin can also be formed in the body from the amino acid tryptophan, therefore, dietary protein quality can impact the nutritional status of niacin. A dose of 60 mg. of tryptophan is equivalent of 1 mg of nicotinic acid. Nicotinic acid in large doses (2 to 6 gm/day) is sometimes used in the treatment of hyperlipoproteinemia; nicotinamide cannot be substituted. |
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Term
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Definition
Pantothenic Acid is converted to coenzyme A and is especially involved in fatty acid oxidation and oxidation of mitochondria (e.g. the formation of acetyl CoA). Therefore, supplementation with vitamin B-complex should be considered in settings of nutrient deficiency like the following:
1. alcoholism,
2. conditions of stress such as heavy exercise, or,
3. increased energy needs associated with severe burns or trauma. |
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Term
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Definition
| Water is lost from skin for thermal regulation. Sweat contains 50 mEq of sodium per liter. Insensible water loss from the skin is approximately 30ml/100 kcal of energy expenditure. |
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Term
| Respiratory Water Exchange |
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Definition
| The quantity of water lost from the lungs is equal to the amount produced from metabolism (metabolic water). Respiratory water loss is approximately 13 ml/100kcal of energy expenditure. Respiratory water loss increases with fever. |
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Term
| Gastrointestinal Fluid Exchange |
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Definition
| Water and electrolytes are secreted through the GI tract down to the duodenum. Fluids are reabsorbed from the jejunum to the colon. Only about 100ml of water per day is lost in the feces. |
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Term
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Definition
| In this state, salt is lost along with water from ECF. Osmolality is adjusted either by increased oral intake or decreased urinary excretion of water. |
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Term
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Definition
| Hypertonic dehydration (water deficit) is due to either inadequate water intake or excessive loss. |
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Term
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Definition
Hypotonic dehydration occurs when the patient loses sodium solution and volume is replaced with a diluted solution containing fewer cations. This imbalance in ECF occurs in diarrheal states. Extracellular volume is restored by treatment with hypertonic and normal saline.
Acute low sodium levels are dangerous because they can lead to brain edema or intractable seizures. |
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Term
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Definition
| It is a key constituent of bone. In other cells, it is in important life-sustaining compounds such as phospholipids, phosphoproteins, and nucleic acids. It is a component of many other phospho-compounds. |
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Term
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Definition
| It is involved in at least 300 enzymatic steps in intermediary metabolism! These include the glycolytic cycle, beta oxidation of fatty acids, and protein synthesis. |
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Term
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Definition
| The most prominent role for fluoride is to reduce the prevalence and severity of dental caries. Most fluoride retained in the body enters calcified tissues (bone and developing teeth). It either substitutes for the hydroxylation or the bicarbonate ion in hydroxyapatite in the bone or enamel to form fluoroapatite. Although no longer considered an essential nutrient, dietary recommendations are provided primarily for the prevention of dental caries. |
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Term
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Definition
| The most prominent role for fluoride is to reduce the prevalence and severity of dental caries. Most fluoride retained in the body enters calcified tissues (bone and developing teeth). It either substitutes for the hydroxylation or the bicarbonate ion in hydroxyapatite in the bone or enamel to form fluoroapatite. Although no longer considered an essential nutrient, dietary recommendations are provided primarily for the prevention of dental caries. |
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Term
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Definition
| Calcium is actively transported across the small intestine, and this process is linked to the active form of vitamin D, 1,25-dihydroxycholecalciferol. Studies indicate that calcium is absorbed equally well from milk and various calcium salts, i.e. carbonate, citrate, gluconate, and lactate. Calcium is rather poorly absorbed with an average of 32% of intake absorbed across populations. The normal range for serum calcium is tightly regulated. (see related diseases) |
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Term
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Definition
| Soluble phosphate found in dairy products and meat are almost completely absorbed. Insoluble phosphates, in vegetables and seeds, are absorbed provided the phosphate can be digested from its ligand. Increases or decreases in dietary phosphorus intake are promptly reflected in changes in serum concentrations and urinary excretion. Vitamin D influences phosphorus absorption and the parathyroid hormone controls phosphorus excretion. |
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Term
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Definition
| GI absorption of magnesium is dose dependent. Under conditions of usual intake, adults absorb 20-30% of the ingested amount. Unlike calcium and phosphorus, absorption is not vitamin D dependent. Magnesium balance relies heavily on renal function. About 70% of serum magnesium is ultrafiltrable and about 95% of the filtered load is reabsorbed. |
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Term
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Definition
| When ingested, 75-90% of fluoride is rapidly and readily absorbed from the GI tract. From the plasma, it forms a complex with calcified tissues and is distributed to either the extracellular or intracellular spaces of the soft tissues or it is excreted. |
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Term
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Definition
Is a universal solvent.
Participates in biochemical reactions.
Provides form and structure to cells.
Is a means of stabilizing body temperature. |
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Term
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Definition
Dissociate into positively and negatively charged ions in water.
Can be simple inorganic salts of sodium, potassium, magnesium or complex organic molecules. |
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Term
| Homeostasis for Salt and Water |
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Definition
The GI tract, kidney and brain regulate the water content of the body.
Thirst |
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Term
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Definition
* in the ventromedial area of the brain
* by the hypothalamus, and
* by anti-diuretic hormone from the pituitary. |
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Term
| Potassium and its regulation |
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Definition
| Potassium is the major intercellular cation in the body. Potassium serves in membrane transport and regulation of the neuromuscular activity. In the ICF potassium concentration approximates 140 mmol/liter. In the ECF it is maintained at 3.5-5.5 mmol/liter. The potential difference across cell membranes is defined by the relationship between the ICF and the ECF potassium concentration. |
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Term
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Definition
| Iron is one of the best understood nutrients because of the relative ease of sampling blood and red cells which represent the major functional pool of iron in the body. Nutritional iron deficiency is commonly regarded as an insufficient iron supply to meet the need for functional iron after storage iron has been depleted. At the cellular level, iron deficiency can also result from insufficient release of stored iron despite ample iron intake and stores, e.g. anemia of chronic disease. In recent years, concern about iron overload in developed countries has been an area of research interest. Most functional iron is in the form of heme proteins. Hemoglobin is the best known heme-compound and has the unique property of easily loading and unloading oxygen. |
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Term
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Definition
| These functions are best classified as: catalytic, structural, and regulatory. Catalytic roles are found in enzymes from all six classes of enzymes and well over 200 zinc metalloenzymes have been characterized. The zinc finger motif in proteins represents an extremely important structural role. |
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Term
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Definition
| Selenium is considered essential for human health. It is a constituent of the enzyme glutathione peroxidase isolated from human red blood cells. Selenium deficiency is rare and occurs in endemic deficiencies, e.g. Keshan disease and in patients on TPN (total parenteral nutrition) without selenium supplementation. |
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Term
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Definition
| an essential element for plants and animals. The redox chemistry of copper makes it well suited for accepting and releasing electrons and for the transfer of electrons to molecular oxygen. Thus, copper-containing enzymes catalyze many reactions involving electron transfer and oxygen. In addition to oxygen transfer, at least three copper enzymes have a role in antioxidant defense |
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Term
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Definition
| osmotic diarrhea, GI disturbances, kidney stones. |
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Term
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Definition
| scurvy, poor wound healing, bleeding gums, perifollicular petechiae, cork screw body hair, fatigue, pain, death |
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Term
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Definition
| green leafy veggies, orange juice or citrus, legumes, fortified grains |
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Term
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Definition
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Term
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Definition
| anemia, homocysteinemia, impaired neural tube defects. |
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Term
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Definition
| part of thiamin triphosphate, which may work w/ neurons. Part of thiamin pyrophosphate, which is required by alpha keto glutarate dehydrogenase, PDH, transketolase. |
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Term
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Definition
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Term
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Definition
Dry beri beri: neuropathy, confusion, confabulation, dementia.
Wet beri ber: heart failure, edema, muscle weakness. |
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Term
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Definition
| as prosthetic groups of flavoproteins, riboflavin derived FAD and FMN catalyze redox reactions. |
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