Vitamins and Minerals Flashcards
(37 cards)
What are the lipid soluable vitamins? Water soluable?
Lipid soluable: A,D,K,E
Water Soluable: B vitamins, C
Vitamin A (functions, deficiencies, susceptible groups)
Functions:
- visual cycle (rhodopsin and cone opsins)
- synthesis of certain glycoproteins and mucopolysaccharides
- retinoic acid - acts as hormone
- antioxidant
Deficiency:
- night blindness (early); xerophthalmia (advanced)
- follicular hyperkeratosis
- anemia (despite normal iron intake)
- poor growth in children
- increased susceptibility to infection and cancer
Susceptible groups: The poor (malnourishment.) Premature babies.
Vitamin D (functions, deficiencies, susceptible groups)
Functions:
- maintaining bone
- calcium homeostasis
- acts as a hormone (receptors are present in many tissues, but full range of activity is unknown.)
Deficiency:
- rickets in children
- osteomalacia in adults
- increased susceptibility to breast and other cancers, metabolic syndrome/diabetes, and infection.
Susceptible groups:
- poor
- elderly
- alcoholics
- the sun-deprived
What are the effects of vitamin D toxicity?
- Bone loss
- Excessive calcium
Vitamin K (functions, deficiencies, susceptible groups)
Function:
- localization of enzymes required for blood clotting
- Helps catalyze addition of γ-carboxyglutamate to clotting enzymes
Deficiency:
- Results in easy bruising, bleeding
- Hemorrhage
Susceptible groups:
- Newborn infants (lack intestinal bacteria that make vitamin K)
- Patients on long-term antibiotics (kills intestinal bacteria)
- The elderly and others with defects in fat absorption
Vitamin E (functions, deficiencies, susceptible groups)
Function:
-Antioxidant: scavenge free radicals,protect membranes from damage, prevent oxidation of LDL
Deficiency:
- Cardiovascular disease
- Neurological symptoms
Susceptible groups:
-Patients with severe, prolonged defects in absorption (ex. celiac disease) or genetic defects (uncommon)
Vitamin C (functions, deficiencies, susceptible groups)
Function:
- cofactor for prolyl and lysyl hydroxylases involved in collagen formation
- required for synthesis of certain stress hormones (response to trauma)
- aids absorption of iron
- has antioxidant activity
Deficiency:
- Mild: bruising, immunocompromise
- Severe: SCURVY (decreased wound healing, osteoporosis, hemorrhage and anemia, fatigue)
Susceptible groups:
- people with poor diet
- smokers
- patients undergoing long-term treatment with aspirin, oral contraceptives, and corticosteroids
What are the 2 sub-categories of B vitamins? Which B vitamins belong to each group?
Energy releasing:
Thiamine (B1)
Riboflavin (B2)
Niacin (B3)
Biotin (B7)
Pantothenic acid (B5)
Pyridoxine (B6)
Hematopoietic:
Folate (B9)
Cobalamin (B12)
Vitamin B1/Thiamine (functions, deficiencies, susceptible groups)
Function:
- Required cofactor for several enzymes in cellular energy metabolism (TPP)
- Particularly critical in nervous system
Deficiency:
- Mild: GI symptoms, depression, fatigue (poor, elderly)
- Moderate: Wernicke-Korsakoff syndrome (alcoholics)
- Severe: Beriberi (people with diet dependent only on polished rice, sometimes alcoholics)
Vitamin B2/Riboflavin (functions, deficiencies, susceptible groups)
Function:
-Precursor of FAD and FMN (coenzymes important in redox reactions of energy metabolism)
Deficiency:
-Ariboflavinosis: rash around nose, inflammation of mouth and tongue, burning and itchy eyes, light sensitivity
Susceptible groups:
-Alcoholics, deficiency is quite uncommon
Vitamin B3/Niacin (functions, deficiencies, susceptible groups)
Function:
-Precursor of NAD and NADP (coenzymes important in redox reactions of energy metabolism)
Deficiency:
-Pellagra: Characterized by dermatitis, diarrhea, and “dementia” (confusion, memory loss, mania)
Susceptible groups:
-People with corn or millet based diets
Vitamin B7/Biotin (functions, deficiencies, susceptible groups)
Function:
-Coenzyme for several carboxylases
Deficiency:
-Rare, but can be caused by eating a lot of raw eggs
Vitamin B5/Pantothenic Acid (functions, deficiencies, susceptible groups)
Function:
- Required for the synthesis of CoA: CoA is a coenzyme for up to 70 different enzymes
- Required for TCA cycle and metabolism of all fats and proteins
Deficiency:
-Very rare. Symptoms are typical of B vitamins
Vitamin B6/Pyridoxine (functions, deficiencies, susceptible groups)
Function:
- Precursor of pyridoxyl phosphate (PLP) enzyme cofactor
- Required for glycogen breakdown, and synthesis of GABA and heme
Deficiency:
- Mild: irritability, nervousness, depression
- Severe: peripheral neuropathy, convulsions, decreased glucose tolerance, hyper-homocysteinemia (cardiovascular risk), anemia
Susceptible Groups:
-Patients treated with certain drugs (isoniazid for TB)
What symptoms are common to most vitamin B deficiencies?
- Symptoms show up first in rapidly dividing tissues. Skin: dermatitis, tongue:glossitis, GI:diarrhea
- Nervous system also affected because of high energy demand: peripheral neuropathy (tingling of extremities,) depression, confusion, lack of coordination, malaise
Vitamin B9/Folate (functions, deficiencies, susceptible groups)
Function:
-precursor of tetrahydrofolate, co-enzyme involved in generating precursors for DNA and protein synthesis.
Deficiency:
- neural tube defects in newborns of deficient mothers
- macrocytic anemia
- hyperhomocysteinemia(cardiovascular risk)
Susceptible groups:
- pregnant women
- the elderly
- alcoholics
- patients with certain long-term drug treatments (Anticonvulsant drugs and oral contraceptives)
- people with genetic polymorphisms in folate metabolism
Vitamin B12/Cobalamin (functions, deficiencies, susceptible groups)
Function:
- coenzyme in methionine synthesis and in conversion of methylmalonyl CoA to succinyl CoA
- needed in folate metabolism
Deficiency:
-Pernicious anemia (megaloblastic anemia) with demyelination
Susceptible groups:
- the elderly
- patients with malabsorption diseases
- long-term vegetarians
Calcium (functions, deficiencies, susceptible groups)
Functions:
- Major component of bone
- Signaling
- Coagulation
- Muscle contraction
- Neurotransmission
Deficiency:
- Mild: muscle cramps, osteoporosis
- Severe: rickets
Susceptible groups:
- Children
- Adult women
- The elderly
Magnesium (functions, deficiencies, susceptible groups)
Functions:
- Essential for many enzymes (which use MgATP as substrate)
- Present at high levels in bone
Deficiency:
-Weakness, tremors, cardiac arrhythmia
Susceptible groups:
- Alcoholics
- Patients taking diuretics, or experiencing severe vomiting and diarrhea
Iron (functions, deficiencies, susceptible groups)
Function:
- O2/CO2 transport in hemoglobin
- oxidative phosphorylation
- cofactor in several nonheme iron proteins and cytochromes (redox properties of iron are important)
Deficiency:
- Microcytic hypochromic anemia
- Decreased immunity
Susceptible groups:
- Children and menstruating women, pregnant women (increased demand)
- The elderly
Phosphorus (functions, deficiencies, susceptible groups)
Functions:
- Mostly present in phosphates
- Major component of bone (hydroxyapatite)
- Constituent of nucleic acids, membrane lipids
- Required in all energy-producing reactions
Deficiency (Rare, abundant in many foods):
- Rickets
- Muscle weakness and breakdown
- Seizure
What are the effects of iron toxicity?
Long-term: Hemochromatosis
- iron overload leads to iron deposits in multiple tissues. Leads to compromised liver, pancreatic, and cardiac function.
- ultimately can compromise mitochondrial function leading to lactic acidosis.
Acute: most common cause of death due to toxicity in children under 6 (Medscape), comes from consumption of adult iron supplements
Copper (functions, deficiencies, susceptible groups)
Functions:
- Assists iron absorption through ceruloplasmin
- Cofactor for enzymes required in collagen synthesis, fatty acid metabolism, and elimination of reactive oxygen species
Deficiency (quite rare):
-Symptoms include anemia, hypercholesterolemia, fragility of large arteries, bone demineralization demyelination
Susceptible Groups:
- Those with genetic disease (Menkes’ syndrome)
- Patients consuming excessive zinc
Zinc (functions, deficiencies, susceptible groups)
Function:
- Cofactor for over 300 metalloenyzmes
- Plays a structural role in many proteins (Zn finger domains)
Deficiency:
- Poor wound healing
- Dermatitis (earliest symptom)
- Reduced taste acuity
- Poor growth and impaired sexual development in children
Susceptible groups:
- Alcoholics
- The elderly
- People with malabsorption or kidney disease
