Vitamins and Minerals Flashcards
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
Chromium (functions, deficiencies, susceptible groups)
Function:
-Component of chromodulin: facilitates insulin binding to its receptor
Deficiency:
-Impaired glucose tolerance (from reduced insulin effectiveness)
Susceptible populations:
-Those with impaired glucose tolerance (Cr3+ hasn’t yet proven helpful in treatment of type 2 diabetics.)
Iodine (functions, deficiencies, susceptible groups)
Function:
-Incorporated into triiodothyronine (T3) and thyroxine (T4) (Regulates basal metabolic rate)
Deficiency:
- Goiter: enlarged thyroid gland
- Hyperthyroidism or hypothyroidism
Susceptible Groups:
-Developing world populations (Iodized salt has reduced incidence)
Selenium (functions, deficiencies, susceptible groups)
Function:
- Component of antioxidant enzymes (ex. glutathione peroxidase)
- Component of deiodinase enzymes involved in T3 and T4 metabolism
Deficiency:
-Keshan disease: cardiomyopathy and cretinism
Susceptible Groups:
-People living in areas with little selenium in soil
What are the most common nutrient deficiencies among alcoholics?
Folate, B6, and thiamine (many others are common)
What are the most common nutrient deficiencies among children?
Iron and calcium
What are the most common nutrient deficiencies among teenagers?
calcium and magnesium, possibly vitamin A, C, and B6
What are the most common nutrient deficiencies among women?
iron, calcium, magnesium, vitamin B6, folate
What are the most common nutrient deficiencies among the elderly?
Vitamins B6, B12, D, possibly zinc and chromium
What is the function of manganese?
Cofactor or structural component for arginase, pyruvate carboxylase, superoxide dismutase.
What is the function of molybdenum?
cofactor/structural component for xanthene oxidase
What is the function of fluoride?
It is incorporated into bones and teeth, strengthening them
What is the function of boron?
it is involved in bone formation.
What is the function of sulfur?
It is a component of amino acids. It is also used in certain post-translational modifications.
