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Digestion and Metabolism > Vitamins > Flashcards

Flashcards in Vitamins Deck (23)
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1
Q

What vitamins are made in the flora? Define what their functions in the body are.

A
Vitamin K - is important in blood clotting process
Vitamin B7 (Biotin) - important in lipogenesis, protein catabolism
2
Q

Define the function, source and deficiencies/toxicity associated with:
Vitamin A

A

Vitamin A (retinol) is found in green vegetables (high in beta-carotene). Vitamin A deficiency presents with poor night vision, dry skin. Toxicity is linked with vomiting and headaches.

3
Q

Define the function, source and deficiency/toxicity associated with:
Vitamin D

A

Calcitriol, when activated in the kidneys, can be found in dairy, eggs and is made in the skin. It functions in Calcium homeostasis and cell differentiation. Deficiency presents as Rickets (in kids) and Osteopenia (in adults); also an increased risk of Alzheimer’s in elderly.

4
Q

Define the function, source and deficiency/toxicity associated with:
Vitamin E

A

Tocopherol is found in veggie oils and SMASH fish. It functions as an antioxidant that reduces damage to lipids. Deficiency here presents as Hemolytic Anemia.

5
Q

Pellagra can result as a deficiency in… This is associated with the 4 D’s of Pellagra which include…

A

Niacin (B3 aka Nicotinic Acid);

Dermatitis, Diarrhea, Dementia and Death

6
Q

High doses of Niacin (B3) can help lower _____ and ____. What are the side effects of B3 toxicity?

A

B3 can lower Cholesterol esters and Triglycerides.

Side effects include flushing, itching, liver damage and impaired glucose tolerance.

7
Q

A deficiency in Thiamin can result in… What are the features of this condition?

A

Thiamin (B1) deficiency can result in Beriberi. This is associated with dry (muscle wasting), wet (edema), infantile (heart failure) and alcoholic conditions. Too much alcohol can impact the liver leading to Wernicke-Korsakoff that is associated with memory loss and slower reflexes.

8
Q

Deficiency in B6 (pyroxidine) can present as ______; whereas, toxicity in B6 can cause _______.

A

Low B6 = convulsions, microcytic anemia, increased risk of cardiovascular damage (high Homocysteine);
OD’d B6 = nerve damage

9
Q

What are the functions of folate (B9) in the body? Why is it so significant?

A

Folate (B9) is involved with DNA and SAM synthesis and methionine recycling processes of the body. Low levels of it in uterus can lead to neural tube birth defects (i.e. spina bifida), megaloblastic anemia and high levels of homocysteine.

10
Q

What are the consequences around the malabsorption of Folate (B9)?

A

Folate malabsorption can lower levels of B12 and increase the frequency of DNA strand breaks thus increasing the risk of cancer.

11
Q

Name 3 effects of Folate Deficiency and briefly describe each.

A
  1. Folate malabsorption - increased dsDNA breaks = increased cancer risk; spina bifida of the fetus with low dietary intake in pregnant women.
  2. Increased homocysteine and SAM = higher risk of CV disease
  3. Megaloblastic anemia = large RBCs with >7 inclusions.
12
Q

What is Vitamin C and its function?

A

Ascorbic acid is a water soluble vitamin obtained naturally from citrus fruits. It acts as an antioxidant that reduces the effects of free radicals in the body.

13
Q

Vitamin C acts as a cofactors in what processes?

A

This is a cofactors in Collagen synthesis, and formation of neurotransmitters as well as other hormones. It can also increase the bio-availability of iron.

14
Q

Where is Vitamin K made? What condition(s) can result if it’s deficient?

A

Vitamin K is made by bacteria in the colon. The prerequisites are acquired from dark green, leafy vegetables. Deficiencies are linked to hemorrhagic diseases (uncontrollable bleeding) since it plays a major role in the clotting cascade.

15
Q

What are the functions, sources and deficiencies associated with:
Vitamin B2.

A

Riboflavin (B2) is a water soluble vitamin that’s involved in energy production (within the Kreb’s cycle; 2 FADH2), neurotransmitter metabolism and RBC production. It’s deficiencies can result in gloss ITIS (smooth tongue), dermatitis and cheliosis (bleeding at lip corners).

16
Q

What are the sources and functions of Niacin (B3)?

A

Niacin (B3) found in fish, poultry, milk and peanuts is involved in energy production (10 NADH in Kreb’s), the reduction of LDL and increase in HDL. It can also reduce TAGs and cholesterol esters.

17
Q

What is the function and significance of Pantothenic acid (B5)?

A

B5 is a water soluble vitamin that is widespread in many foods. It has an ESSENTIAL role in making Coenzyme A within Acetyl CoA for energy production. It’s deficiency/toxicity is rare.

18
Q

What conditions result from a deficiency in Vitamin B7 (Biotin)? What can cause B7 deficiency?

A

Eating too many raw eggs raises Avidin which reduces the bio-availability of B7 which can result in depression, dermatitis, neurological disturbances and conjunctivitis.

19
Q

What are the functions and sources linked to:

Vitamin B6.

A

Pyroxidine (B6) handles >100 enzymatic reactions when in active PLP form. It can be obtained from a diet with poultry, fish and pork. It also functions in making non-essential AAs, heme synthesis and conversion of L-Dopa to Dopamine.

20
Q

What conditions are associated with Vitamin B6 deficiency?

A

Lower PLP (vitamin B6) levels are associated with…

  1. Microcytic anemia (with similar presentation to iron deficiency) - small pale RBCs
  2. Convulsions
  3. High homocysteine (increased risk of CV disease)
21
Q

What is the significance of the toxicity of taking too much folate (B9)?

A

Too much B9 can increase the risk of cancer since folate play a role in normal cell division. This can mask the anemia associated with B12 deficiency.

22
Q

What are the functions and sources of Vitamin B12?

A

Vitamin B12 (Cobalamin) can be found in meats, milk and poultry. It activates folate, synthesizes DNA, regenerates methionine form homocysteine and maintains the sheath of nerve fibers.

23
Q

What condition is associated with the deficiency of Vitamin B12?

A

Deficiency in Vitamin B12 (cobalamin) can result in Pernicious anemia and high levels of methylmalonic acid. This correlates to fatigue, muscle weakness, nausea and a sore mouth.