Fat Soluble Vitamins

Question 1

What are dietary sources of Vitamin A?

Answer 1

from retinol esters in animal sources and beta carotene (pro-vitamin A) in plant sources
- carrots, cantaloupe, broccoli, eggs, milk

Question 2

What are dietary sources of Vitamin D?

Answer 2

milk and sunshine

Question 3

What are dietary sources of Vitamin K1?

Answer 3

green veggies like broccoli, spinach, and asparagus

Question 4

What are dietary sources of Vitamin K2?

Answer 4

gut micro-flora in the large intestine

Question 5

What are dietary sources of Vitamin E?

Answer 5

nuts/seeds, salmon

Question 6

What is the role of Vitamin A?

Answer 6

• essential to vision, promotes healthy surface linings of eyes, respiratory, urinary, and intestinal tracts
• effective anti-oxidant
• control lipid per oxidation
• cell differentiation

Question 7

What disorders are associated with Vitamin A deficiency?

Answer 7

• night blindness
• Xerophthalmia - dry eyes and inability to produce tears
• Keratomalacia - softening of the cornea
• Bitot’s spots- abnormal surface of the eye

Question 8

What sort of issues are associated with too much Vitamin A?

Answer 8

hypervitaminosis A

• Acutely: nausea/vomiting/vertigo
• Chronically: ataxia, alopecia, hyperlipidemia etc.
• Teratogenic: spontaneous loss of fetes or fetal malformations

Question 9

what are the therapeutic uses of Vitamin A?

Answer 9

they are used for hyperkeratotic and hyper proliferative skin disorders - and they reduce proliferation of sebaceous glands (treat acne)

Question 10

Who is most at risk of a vitamin D deficiency?

Answer 10

• breast fed infants
• dark skin
• elderly
• fat malabsorption syndromes
  inflammatory bowel disease

Question 11

What is Rickets?

Answer 11

vitamin D deficiency in children leads to reduction in Ca absorption

Question 12

What is osteomalacia?

Answer 12

reduction in Ca Absorption in adults

Question 13

What is the result of too much Vitamin D?

Answer 13

Hypervitaminosis D = can lead to hypercalcaemia (calcium deposits in tissues, joints, lungs, brain and kidney) constipation, decreased appetite and muscle weakness

Question 14

plasma concentration of what vitamin product correlates with plasma lipid and cholesterol levels?

Answer 14

concentration of Vitamin E

Question 15

what is the role of Vitamin E in the body?

Answer 15

Anti-oxidant role : acts as free scavenger- protects polyunsaturated fatty acids from per oxidation, protects fats in LDL from oxidation

non-oxidant role: inhibition of protein kinase C, modulates cellular transport of retinoic acid, down regulates expression of oxidised LDL scavenger receptors in smooth muscle cells

Question 16

What can cause a Vitamin E deficiency?

Answer 16

severe malnutrition, disorders of fat metabolism, genetic defect in alphaTTP (carrier protein)
symptoms: neuromuscular - myopathy or ataxia and haemolysis

Question 17

What needs to be intact for proper vitamin K absorption?

Answer 17

pancreatic and biliary function - dietary vitamin K is cleaved from its carrier protein by pancreatic enzymes in the small intestine - bile salts solubilise it for absorption into micelles and chylomicrons - it is transported to the liver for storage via the lymph system

Question 18

what is the physiological role of Vitamin K?

Answer 18

they have a major role in the coagulation cascade

Question 19

What is the cause of vitamin K deficiency? What is the result?

Answer 19

• common in newborns
• in adults primary deficiency is uncommon
• acquired deficiency is a result of long term use of antibiotics
  mucosal bleeding results, as well as easy bruising, melon, splinter haemorrhages…