Vitamins Flashcards
sources of vit D
egg yolk, fish oil and plants
What is the Precursor for Vitamin D
Ergosterol
What Does Excess Vit D cause?
nausea and muscle weakness
calcium absorption
bone resorption
What Does Deficiencies of Vit D cause in the Oral Cavity?
increase risk of caries and periodontal disease
enamel and dentine hypoplasia
How does Vit D Activate?
ergosterol converted to ergocalciferol
7-dehydrocholestrol converted to cholecalciferol
catalysed by 1,25-dihydroxyvitamin D3
is vitamin D water soluble?
no
is vit D fat-soluble and what happens to it in excess?
yes, stored in fat and adipose tissue
What happens to water-soluble vitamins in excess?
non-toxic and excreted in the urine
Give 3 water-soluble vitamins.
vitamin C
vitamin B9 (Folic Acid)
vitamin B12
2 Forms in which vit C exists.
Ascorbic Acid
Ascorbate Salts
Sources of Vit C
fruit and veg
What are 3 the Functions of Vit C
antioxidant - prevents Fe2+ into Fe3+
Collagen synthesis
iron absorption
What does vit c deficiency lead to?
scurvy, mild anaemia, damage to blood vessels
Which Groups are at Risk of Vit C Deficiency?
elderly
alcohol/drug abuse
smokers
infants who primary source of milk is cows
renal failure and dialysis
malabsorption conditions
What are the Oral Symptoms of Vit C Deficiency?
initial = gingival inflam
progressive = impaired collagen synthesis
What can Reduce the effect of ascorbic acid?
sodium ascorbate
Sources of B9
green leafy veg, liver, nuts, cereals
Function of B9
DNA synthesis
cell division
nucleic acid synthesis
What does Deficiency of B9 Lead to?
megaloblastic anaemia hair loss
fatigue
heart disease
birth defects
- spina bifida and anencephaly
- neural tube doesn’t close
What are the Oral Symptoms of Vit 9 Deficiency
during pregnancy, cleft lips risk are high
Where is B12 Stored?
liver
sources of B12
meat, eggs, dairy
Function of b12
folate metabolism
maintain low homocysteine level
blood formation
nerve functioning
When is a Deficiency of B12 caused?
insufficient intrinsic factors
What does a deficiency of B12 lead to?
damage to growing cells
neurological symptoms
fatigue
chronic pain
infertility
blood disorders
Which groups are at risk of vit B12 Deficiency?
strict vegetarians
elderly
malabsorption diseases
side effects of medication
How is B12 Absorbed and Transported?
- B12 binds to glycoprotein in stomach
= vitamin-intrinsic factor - surface receptors in ileum recognise
= absorbed - transported and binds to a B12 binding protein (transcoblamin)
- stored in the liver
Why is it Hard to Detect B12 Deficiency
blood tests dont differentiate between active form and non active form
How do you Detect b12 Deficiency
two step blood test
- determine holotranscobalamin content
- determine metabolic product concentration
- if theres methylmalonic acids and homocysteine
= lack of B12
How is B12 Administered?
intravenously asap
Oral Symptoms of B12 Deficiency
glossitis
angular cheilitis
ulcers
high caries rate
gingival problems in children below 11
What Medications can Induce Vitamin Deficiencies, what Diseases are they taken for?
Proton Pump Inhibitors
- Vitamin B12 and C
- gastroesophageal reflux disorder
Metformin
- Vit B12
- diabetes
Levodopa
- Vit B12
- Parkinson’s
