Chapter 7 Flashcards
What are vitamins?
Organic molecules needed in very small amounts for cellular metabolism
Vitamins perform what?
Specific metabolic functions
Vitamins are essential nutrients to be provided by what?
Diet
What are water soluble vitamins?
B complex vitamins
Choline
Vitamin C
What are characteristics of water soluble vitamins?
- Minimal storage
- deficiencies develop more -quickly usually low risk of toxicity
What are fat soluble vitamins?
Vitamin A
vitamin D
vitamin E
vitamin K
What are characteristics of fat soluble vitamins?
-Excess stored in body -deficiencies longer to develop -greater risk of toxicity
Vitamins are in almost all foods but it is best to consume vitamins from what?
Food sources
synthetic vitamins (supplements) perform same vitamin function but may lack what?
Other benefits found in foods
What are phytochemicals?
Non-nutritive substances in plant-based foods that appear to have disease fighting properties
What is the function of Thiamine (B1)?
Coenzyme for energy metabolism.
Role in muscle contraction and conduction of nerve cells.
What are types of thiamine deficiency’s?
Beriberi: ataxia and tachycardia
What is the toxicity of thiamine?
Nontoxic
What is the function of riboflavin (B2)?
Coenzyme in energy release
What are riboflavin deficiencies?
Ariboflavinosis: cheilosis, glossitis, seborrheic dermatitis
What is what is the toxicity of riboflavin?
Non-toxic
What is the function of niacin(B3)?
Energy metabolism
What are niacin deficiencies?
Pellagra: the 3 ads: diarrhea, dermatitis, dementia
What is the toxicity of Niacin?
Causes vasodilation and Flushing effect
What is the function of pyridoxine (B6)?
Coenzyme in metabolism of amino acids and proteins
What are pyridoxine deficiencies?
Accompanies low intakes of other B vitamins
What is the toxicity of pyridoxine?
UL 100 mg/day
-Megadose supplementation may cause ataxia and sensory neuropathy
What is the function of folate (B9)?
- Required for synthesis amino acids, DNA and RNA
- forms the heme portion of hemoglobin
- Role in proper formation of fetal neural tube affecting brain and spinal cord
What are folate deficiencies?
-Results in megaloblastic anemia, glossitis, diarrhea, irritability, absentmindedness,
depression, anxiety
-drug nutrient interactions: Anticonvulsants, oral contraceptives, aspirin
What is the toxicity of folate?
UL 1000 mcg folic acid (excessive intake may mask B12 deficiency)
What is the function of cobalamin (B12)?
- Required for metabolism of fatty acids and amino acids
- Develops and maintains Myelin sheaths around nerve fibers
what are colabamin deficiencies?
Results in megaloblastic anemia or pernicious anemia
What is the toxicity of cobalamin?
Unknown
What is the function of biotin (B7)?
Important role in CHO, fat, and protein metabolism
What are Biotin deficiencies?
-Possible with intravenous feeding’s, long-term anabiotic use, and consumption of language
What is the biotin toxicity?
Unknown
What is the function of pantothenic acid (B5)?
Metabolism of carbohydrates fats and proteins
what are pantothenic acid deficiencies?
Unknown
what is the toxicity of pantothenic acid?
10 to 20 g may produce diarrhea or water retention
What is the function of choline?
Synthesis of acetylcholine (neurotransmitter) and lecithin (The phospholipid)
What is the toxicity of choline?
UL of 3500 mg adults Symptoms include sweating fishy body odor vomiting liver damage reduced growth low blood pressure
What is the function of vitamin C
- Antioxidant and coenzyme
- Wound healing: collagen formation
- Enhances absorption of nonheme iron -evidence does not support reduced incidence of common cold:Supplementation may decrease ration and severity of symptoms
What are deficiencies of vitamin C
- Scurvy
- marginal deficiencies are poor wound health
- gingivitis
- in adequate tooth and bone growth and maintenance
- increased risk of infection
What is the toxicity of vitamin C
UL 2000mg adults; 400mg to 1800mg for children and adolescents
-Chronic supplement result in cramps, diarrhea, nausea, kidney stones, gout, may interfere with anti-clotting medication
What is the function of vitamin A
Maintains skin and mucous membranes Vision bone growth immune system function normal reproduction
What are vitamin a deficiency’s
- Xerophthalmia: ranges from night blindness to keratomalacia
- immune system impaired
- respiratory infections diarrhea and other G.I. disturbances
- Growth inhibited; limited bone growth
What is vitamin a toxicity
Hypervitaminosis and
Excess beta carotene
What is the function of vitamin D
Absorption of calcium and phosphorus, affects bone mineralization
What are vitamin D deficiencies
- Children:Ricketts
- adults:osteomalacia
- osteoporosis
What is the toxicity of vitamin D
UL of vitamin D 100 mcg (4000 IU)
What is the function of vitamin E
Antioxidant
What are vitamin D deficiencies
Primary deficiency is rare but symptoms include neurologic disorders and anemia due to hemolysis of RBCs
What is the toxicity of vitamin E?
UL of 1000mg a-TE
What is the function of vitamin K
Synthesis of blood clotting factors and contributes to pro team formation in Bone, kidney, and plasma
What are vitamin K deficiency’s
Inhibits blood coagulation,
newborns given intramuscular injection to prevent hemorrhagic disease
What is the toxicity of vitamin K
Excess amounts of supplements decrease effectiveness of anticoagulant medications and may increase stroke risk
What are ways to overcome barriers of proper vitamin intake
Swallowing a pill and rethinking vitamin supplementation
Which of the following or water soluble vitamins and must therefore be consumed on a more regular basis?
A. Vitamins C, E , A
B. Vitamins K, E, D
C. Vitamins C, folate, B
D. Vitamins K, E, folate
C
