2. Vitamin Name. Source. Function. De2ciency. Toxicity. Comment
Vitamin A
Retinoids (retinol, retinal and
retinoic acid) from animals
Carotenoids (ß- carotene) from
plants, Retinyl palmitate in liver
- Carrots
- fortified milk
- Cold-water fish (salmon)
Antioxidant, Night vision, treat
skin diseases (acne), hormone
actions in gene expression,
glycoprotein synthesis,
- Night blindness
- dry skin
- susceptibility to infections
Liver damage, Alopecia,
headache, dry skin, birth
defects, yellow/orange skin
In vision cycle, Trans-retinol converted
to 11- cis-retinal and bound to opsin to
form Rhodopsin
Vitamin D
Ergocalciferol (D2) from plants
Cholecalciferol (D3) from animals
and endogenous cholesterol
- Butter
- fortified milk
- Fatty saltwater fish (salmon, tuna)
Steroid hormone regulating
calcium & phosphorus, bone and
teeth, formation Maintain stable
nervous system and heart action,
- Rickets (infants)
- Osteomalacia (adults)
- tooth decay
- retention of phosphorus
25,000-200,000 IU, Calcification,
damage to kidneys & heart,
waek bones & muscles
Regulated by PTH.
In liver, hydroxylated to 25-hydroxyvitamin D
(25(OH) D) & in kidney further hydroxylation to
1,25-dihydroxyvitamin D (1,25(OH)2 D)
Vitamin K
Phylloquinone (K1) from plants
Menaquinone (K2) intestinal flora
Menadione (K3) synthetic
provitamin of K2
- 65 micrograms (women) &
- 80 mcg (men).
- Broccoli, spinach, milk
- Formation of blood
- clotting proteins
(prothrombine, factor 7,8, and 10)
Caused by Coumarin derivatives
such as Warfarin and dicumarol.
Causes Liver disease, Intestinal
disease
Hemolytic anemia, Jaundice
Cofactor to carboxylase
that generates gamma-
carboxyglutamic acid
Vitamin E
Tocopherols, eight forms
(Alpha tocopherol most active)
- Almonds, salmon Antioxidant Deficiency symptoms are
very rare
3,000 IU. May interfere with
Vitamin K activity leading to
prolonged clotting and
bleeding time
Vitamin C
Ascorbic acid, dehydroascorbic
acid (oxidized)
- 75 mg (women)
- 90 (men).
- Orange, Citrus fruits
- Guava, Broccoli, Spinach
Antioxidant, protects cells and
keeps them healthy, aid absorption
of iron, synthesis of carnitine &
collagen
Scurvy, breakdown of
connective tissue,
spotted skin, inflamed gums,
Vitamin B1
Thiamine, Thiamin pyrophosphate
(TPP, active form)
- 1.1 mg (women)
- 1.5 (men).
- Fortified breads & cereals,
- fish, milk
Coenzyme in the catabolism of
sugars and amino acids
Beriberi, weight loss, edema,
increase lactic acid & pyruvic
acid, high-output cardiac
failure
Vitamin B2
Riboflavin forms two coenzymes:
Flavin mononucleotide (FMN) by
riboflavin kinase, Flavin adenine
dinucleotide (FAD) by FMN &
adenylyltransferase
- 1.3 mg. beef
- milk
- spinach
- almonds
Coenzymes in growth of cells,
energy production, maintaining
normal levels of homocysteine
Appear pale, cracks in
mouth & lips, tongue may
turn magenta, patches
FAD in conversion of tryptophan
to niacin (vitamin B3). FMN in
conversion of vitamin B6 to
pyridoxal 5'- phosphate
-Vitamins Summary-
Jahfar
1
Beriberi types: Wet (cardiovascular system),
Dry (nervous system) Acute (babies),
Gastrointestinal (digestive system).
Risk factors include a diet of mostly white
rice, alcoholism, dialysis, diuretics.
↑
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3. Vitamin Name. Source. Function. De2ciency. Toxicity. Comment
Vitamin B3
- 14 mg (women)
- 16 (men)
- Meat
- fish, nuts
Coenzyme for 400 enzymes,
keeps nervous & digestive
systems & skin healthy
- Pellagra
- dark scaly rash
- constipation/ diarrhea
- bright redness of tongue
High-dose supplements of
nicotinic acid, not nicotinamide.
A reddened skin flush with
itchiness on face & arms
Pellagra has two types: Primary
(not enough in diet), Secondary
(unable to absorb niacin)
Vitamin B5
Pantothenate ,pantothenic acid - 5 mg. All foods
(meat
vegetables
milk)
biosynthesis of coenzyme A (CoA)
and acyl carrier proteins in
Very rare, only in severe
malnutrition
Phosphorylated by ATP to form
coenzyme A
Vitamin B6
1.3 mg.
Beans,
nuts, eggs, meat
Formation and breakdown of amino
acids, neurotransmitter & hemoglobin
synthesis, gene expression
Because: Celiac disease,
homocystinuria, antiepileptic
drugs. Causes: Microcytic anemia,
dermatitis with cheilosis, glossitis
Prevent or treat peripheral
neuropathy caused by
medications such as isoniazid
Vitamin B9
Folic acid, Folate 400 micrograms.
Spinach, broccoli,
fruits
Prevent birth defects of the
baby's brain (anencephaly) &
spine (spina bifida)
Because: lack of dietary folate in
unbalanced & unhealthy diet, alcohol.
Causes: Extreme tiredness, mouth
ulcers, muscle weakness.
Implicated in the
development of
colorectum cancer
Vitamin B12
Cobalamins(contains cobalt).
Methylcobalamin & 5-
deoxyadenosylcob alamin are
active forms
2.4 micrograms.
Meat, fish &
dairy products
Required for myelination &
function of CNS, RBC formation,
DNA synthesis. Cofactor for two
enzymes, methionine synthase and
L- methylmalonyl-CoA mutase
Anemia, fatigue, muscle
weakness, nerve damage
-Vitamins Summary-
Jahfar
2
Niacin (nicotinic acid &
nicotinamide). Tryptophan can
be converted to nicotinamide.
Pyridoxine (Pyridoxal),
Aminotransferase. Pyridoxal
phosphate and pyridoxamine
phosphate are active coenzymes.
Note: Vitamin A,D,K,E are Lipid- soluble. Vitamin C & B are Water-soluble
Relationship to Pernicious anemia
(PA). Hydroxycobalamin &
Cyanocobalamin, become active
after conversion to methylcobalamin
& 5- deoxyadenosylcob alamin
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