Transcript Vitamins

Dr.S.Nishan Silva
(MBBS)
Vitamins
• Definition:
–Chemically unrelated organic
compounds that are essential for
normal metabolism
• Cannot be synthesized, therefore
must be ingested
Vitamins
(Fat Soluble)
• Vitamin A, D, E, K
(Water Soluble)
• Vitamin C and the B
vitamins
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B1-Thiamine
Riboflavin
B3-Niacin
Pantothenic acid
Biotin
B6-pyridoxine
B12
folate
Vitamin deficiency
• Gross deficiencies are recognized by
clinical syndromes
• Are seen in poorer areas
• Seen in Western societies in special
populations
– Elderly, vegans, new immigrants, the very
poor, alcoholism, malabsorption (hx gastric
bypass), parenteral nutrition
Vitamin A
• First fat soluble vitamin to be discovered
• Part of compounds called retinoids
• Essential for vision, immune response, epithelial
growth and repair
• Can store 1 year of reserve
• RBP=retinol binding protein-bonds to Vitamin A
in blood
Requirements
• Males > 10 y need 1000mcg
• Females > 10y need 800 mcg
• only 40-60% plant bioavailability vs 8090% of animal protein
• Zinc and/or Iron deficiency can interfere
with metabolism
• LABS
– -RBP, FBC, serum retinol(costly)
Vitamin A deficiency
• Complications
– Dry skin, dry hair, broken nails-may be first
sign
– Night blindness
– Xeropthalmia-no tears-predisposes to
blindness
– Hyperkeratosis-goose bump skin
Vitamin A deficiency
Night Blindness
Imagine you are in the car at the
left and this is what you see.
Car approaches, note sign on the right.
Normal vision
Car passes. Notice distance down the road, signs.
Night Blindness
Eye fails to
adapt quickly to
decreased light.
Car passes. Notice distance down the road, signs.
Vitamin A
deficiency.
Human
shoulder.
Follicular hyperkeratosis. Goose flesh. Pustulation
occurs and is confused with acne.
Bitot's spots
are the buildup of keratin debris located superficially in the conjunctiva,
which are oval, triangular or irregular in shape.
Xerophthalmia
caused by a severe vitamin A deficiency is described by
pathologic dryness of the conjunctiva and cornea
Vitamin K
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Found in green, leafy vegetables and oils
Plays a role in coagulation cascade
Body’s reserve lasts one week
85% absorbed in terminal ileum
Vitamin K deficiency
• Def due to
– chronic illness, multiple abdominal surgeries,
liver or biliary disease, alcoholism, drugs:
Antibiotics(cephalos) Coumadin, salicylates,
sulfa
• Clinical Manifestations
– Bleeding, hematoma, ecchymosis
Easy Bruising
Epistaxis
Echymosis
It’s a brain of a baby.
Vit K deficiency in man. Hemorrhagic disease of
newborn. Reason for Vit K injection at birth.
Vitamin K deficiency
• Labs:
– Pt/Ptt (INR)
– Vit K level (0.2-1 ng/ml)
• RX
– Replace Vit K IM( 10 mg/d) , SQ, or PO (5-20
mg)
– FFP( begin- 2 Units)
Vitamin D
• Few foods contain Vit D (fatty fish and
eggs)
• Dermal synthesis or fortified foods (milk)
are the main source
• Two forms of Vitamin D– Ergocalciferol -Vit D2
– Cholecalciferol-Vit D3
Vitamin D Metabolsim
• Vitamin D3 is synthesized in the skin
during UV light exposure
• Vit D3 from skin or diet is then
hydroxylated in the liver, then kidneys to
active form Vit D dihydrohycholecalciferol
(calcitriol)
Prevalence
(D Deficiency)
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MSK pain (unrecognized !!!!!!)
Hospitalized pts
Women being treated for OP
CKD (usually 1,25DOH but also 25OHD
GI malabsorption
Gastric bypass
Cystic fibrosis
Extensive burns
Vitamin D deficiency
• Independent predictors
– Low Vitamin D intake
– Winter
– Housebound status
• Who should be tested?
– Institutionalized or home bound
– Suspected malabsorption
– Evaluation of osteoporosis
Osteoporosis
Postmenopausal women with low 25 OHD levels
have lower bone densities (3)
Rickets
Vitamin D serum levels
• Test to order: serum 25 OH Vit D
(calcidiol)
• Normal 30-32 ng/ml(75-80mmol/L)
• “levels of 28-40 may lower the fracture
risk”
• Example definitions of deficiency – Vit D
– Vit D Insufficiency= 20-30ng/ml
– Vit D Deficiency=< 20 ng/ml
Optimal intake
• 1997 national academy of sciences
recommendation:
– 400IU/d age 51-70
– 600 IU/d age > 71
– However more recent data shows avg adult
needs 800-1000IU/d to maintain level of 30
– Older persons confined indoors may have low
levels even at this intake
Vitamin D supplementation
• For every 40 IU of D3 given, serum
increased by 0.3-0.4 ng/ml
• Rx for deficiency
25-OH D
– PO: 50,000 units of D3 q week x 6-8 weeks, then 8001000 IU daily
– IM : D3 (300,000 IU) in 1 or 2 doses per year
• Rx for Insufficiency
– 800-1000 IU of D3 daily( will bring avg adult to serum
level of 30 in 3 months)
• Measure serum levels after 3 months of starting
rx
Vitamin B12
• Deficiency causes:
– Neurologic disease
– Megaloblastic anemia, pernicious anemia
– May be important cause of hyperhomocysteinemia
(CV disease, OP)
• Subtle deficiency even without anemia may
cause dementia and ?balance problems
B 12 Deficiency
• Hematologic
– Megaloblastic anemia
– Pancytopenia (leukopenia, thrombocytopenia)
• Neurologic
– Paresthesias
– Peripheral neuropathy
– Combined systems disease (demyelination of dorsal
columns and corticospinal tract)
• Psychiatric
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Irritability, personality change
Mild memory impairment, dementia
Depression
Psychosis
• Cardiovascular
– Possible increased risk of myocardial infarction and
stroke
Megaloblastic Anaemia
Suboptimal B-12 deficiency
• Caused by poor absorption and
inadequate intake
• Malabsorption-cobalamin unable to
release from dietary proteins esp with low
gastric acid secretions
• Alcoholism
Peripheral Neuropathy
B12 level
• Normal-> 300 pg/ml cobalamin deficiency
unlikely
• Borderline 200-300-deficiency possible
• Low < 200 -deficiency
Recommendations for B12
supplementation
• Older adults - 6mcg daily
• Vitamin supplements have 100 mcg/dose
• May be inadequate dose in:
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Elderly
Atrophic gastritis
Vegans
Gastric bypass sx
Alcoholics
Poor dietary intake
Folic acid
• Found in green leafy vegetables, fruits,
cereals, nuts, mats
• Folic acid (the supplement form) has same
effect but more bioavailable than folate
• Deficiency leads to megaloblastic anemia
Folic Acid in Pregnancy
• Decreases risk of neural tube defect
• Appears dose dependent
- In one study
400 mcg decreased rate of NTD by 57%
5000mcg decreased rate by 85%
Folic acid in Cardiovascular
Disease
• Elevated homocysteine
associated with increased risk of
CV disease
• Folic acid, B6, B12 can decrease
homocysteine
Vitamin C – Ascorbic Acid
• Vitamin C is a water-soluble vitamin
• You need vitamin C for the growth and repair of
tissues in all parts of your body.
• It helps the body make collagen, an important
protein used to make skin, cartilage, tendons,
ligaments, and blood vessels.
• Vitamin C is needed for healing wounds, and for
repairing and maintaining bones and teeth.
Vit C Deficiency
• Dry and splitting hair; gingivitis
(inflammation of the gums) and bleeding
gums; rough, dry, scaly skin; decreased
wound-healing rate, easy bruising;
nosebleeds; and a decreased ability to
ward off infection. A severe form of vitamin
C deficiency is known as scurvy.
Vit C Deficiency
• Low levels of vitamin C have been
associated with a number of conditions,
including high blood pressure, gallbladder
disease, stroke, some cancers, and
atherosclerosis, the build-up plaque in
blood vessels that can lead to heart attack
and stroke.
• Recommended amounts
–Men over 18 years: 90 mg
–Women over 18 years: 75 mg
• Treatment
–2 - 3 times per day, with meals,
depending on the dosage.
– Adults should take 250 - 500 mg
twice a day for any benefit
.
Vitamin E
• Vitamin E - fat soluble compounds with
strong antioxidant properties.
• Isomers of tocopherol and torcoretinol
• People aged 14 years or more - 15 mg per
day
Vit E Deficiency
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1. Anemia
2. Poor Balance
3. Muscle Weakness
4. Sight Problems
Nervous system problems – sensation loss,
pain, and tingling – in the arms, hands, legs, and
feet may signify vitamin E deficiency.
Treatment with Vit E
• From 200 - 2400 IU daily depending on
condition
• Capsules for hair loss
• Given for muscle cramps
Vitamin B1 – Thiamin
• Vitamin B1, helps fuel by converting blood
sugar into energy.
• It keeps your mucous membranes healthy
and is essential for nervous system,
cardiovascular and muscular function.
• Women should have 1.1 milligrams every
day,
• and men should have 1.5 milligrams every
day.
Treatment with Thiamin
• Mild deficiency - usual dose of thiamine is
5-30 mg daily
• severe deficiency can be up to 300 mg per
day
• As a dietary supplement in adults, 1-2 mg
of thiamine per day
• 100mg IM for treating and preventing
symptoms of alcohol withdrawal
(Wernicke-Korsakoff syndrome).
Vitamin B2 - Riboflavin
• Riboflavin (vitamin B2) is manufactured in the
body by the intestinal flora and is easily
absorbed
• Vitamin B2 is required for the health of the
mucus membranes in the digestive tract and
helps with the absorption of iron and vitamin B6.
• RDA: 1.2 Mg - 1.7 Mg.
Therapy : 25 - 50 Mg.
Vitamin B3 - Niacin
• Has 2 other forms, niacinamide (nicotinamide)
and inositol hexanicotinate
• Men 19 years and older: 16 mg (RDA)
• Women 19 years and older: 14 mg (RDA)
• Therapy : 100 Mg or more with meals (For
alcoholics, Migrain)
Pellegra. Niacin deficiency.
Dermatitis, diarrhea, dementia.
Same patient after niacin treatment.
Vitamin B5 – Pantothenic acid
• “anti-stress vitamin"
• Vitamin B5 plays an important role in the
secretion of hormones, such as cortisone
because of the role it plays in supporting
the adrenal gland.
• RDA: est 4 - 7 Mg daily.
Therapy: 50 - 200 Mg
Vitamin B5 Deficiency
• Fatigue, headaches, nausea, tingling in
the hands, depression, personality
changes and cardiac instability
• Frequent infection, numbness, paresthesia
,muscle weakness and cramps.
• Increased insulin sensitivity, lowered blood
cholesterol, decreased serum potassium,
and failure of adrenocorticotropin to induce
eosinopenia.
Vitamin B6 - Pyridoxine
• Pyridoxine is required for the balancing of
hormonal changes in women as well as
assisting the immune system and the
growth of new cells.
• RDA : 1.8 - 2.2 Mg.
Therapy : up to 200 Mg daily over
several months.
Vitamin B6 Deficiency
• Irritability, nervousness and insomnia ,
general weakness, dermatitis and acne ,
asthma and allergies
• Nails get ridged, an inflamed tongue ,
osteoporosis and arthritis. Kidney stones
may also appear.
Biotin
• Also called Vitamin B7, Vitamin H
• Foods include Swiss chard, raw egg yolk,
liver, some vegetables and peanuts.
• Hair loss, Diabetes. ,Diabetic nerve pain,
Brittle fingernails and toenails, Other
conditions.
• 30 mcg for adults over 18 years
Toxicity
• Water soluble vitamins
– toxic at thousands x the DV
– Vitamin C-increased risk of kidney stonescontroversial
• Fat soluble vitamins
– Vit D- hypercalcemia at dose of 2000IU/d
– Vitamin A –pregnancy-teratogenic
– Vitamin E- above 400 IU may be associated with all
cause mortality
Toxicity
• Vitamin A -HA, dizziness, blurred vision,
clumsiness, birth defects,
• Vitamin D-Constipation, weakness, anorexia,
weight loss, confusion
• B3-Niacin-Flushing, redness of skin,
• B6-pyridoxine-Numbness, paresthesia, ataxia
• Vitamin C-kidney stones
• Folate-can mask B12 deficiency