Met 2: Water Soluble Vitamins Flashcards
Does intake of water soluble vitamins alter tissue levels?
Acute intake doesn’t but chronic intake can alter tissue levels
What 3 micronutrients are important for energy-releasing (catabolic) reactions?
Thiamin (B1) , riboflavin (B2), niacin (B3)
What is one source of Thiamin/B1, Riboflavin/B2, Niacin/B3?
Whole and enriched grains
What micronutrient is made from Tryptophan?
Niacin (B3)
Name the 3 types of Thiamin (B1) deficiency and 1 feature of each
All B1 deficiency is considered “Beriberi”
- Dry Beriberi: peripheral neuropathy
- Wet: congestive heart failure
- Wernicke-Korsakoff: cerebral effects
Name 4 symptoms of Wernicke-Korsakoff syndrome
- Ataxia
- Confusion
- Ophthalmoplegia
- Later, get memory loss
4 groups of people who get thiamin deficiency
- Alcoholics
- Bariatric surgery pts
- Anorexia and re-feeding syndrome
- Southeast Asian immigrants
2 symptoms of B2/Riboflavin Deficiency
Cheilosis and angular stomatitis
(both are lesions at corner of mouth)
Patients who have a cornmeal based diet are at risk for….?
Pellagra (aka Niacin/B3 deficiency)
Name the 4 D’s of Pellagra (Niacin/B3 deficiency)
- Diarrhea
- Dermatitis
- Worse in sun exposed areas
- Peeling with both hyper and hypopigmentation
- Dementia
- Death
Functions of folate (4)
- Single carbon transfers
- nucleic acid synthesis and amino acid metabolism
- DNA methylation
Sources of folate (2)
foliage!
grains in USA are fortified
Patients with autoimmune hemolytic anemia will need supplementation of _____
Folate
4 Sx of folate deficiency
- Macrocytic anemia
- Hypersegmented neutrophils
- Glossitis
- Elevated homocysteine
Why is folate fortified in our grains?
Prevent neural tube defects in infants
Neural tube closes before women even realize they are pregnant
Functions of B12 (2)
- Helps folate do its job
- B12 reforms tetrahydrofolate from methylfolate
- Lipid and fat metabolism
Describe absorption and transport of B12 (4)
- Vitamin 12 is cleaved from dietary protein in stomach
- Binds Intrinsic Factor, which gets released in stomach
- Cobalamin-IF absorbed in ileum
- Transported in circulation as Transcobalamin II
What one water soluble vitamin has large stores?
Where?
B12 has large stores in liver
What is the source of B12?
What group is therefore at risk of deficiency?
- B12 found in animals products
- synthesized by soil bacteria and then eaten by animals
- Vegans at risk of deficiency
4 symptoms of B12 deficiency
Reversibility?
- Macrocytic anemia
- hypersegmented neutrophils
- Combined subacute neurologic degeneration
- Glossitis
Neurologic symptoms are EVENTUALLY IRREVERSIBLE
5 Functions of Vitamin C
- Antioxidant
- Provides reducing equivalents (eg. reduces iron)
- WBC function
- Needed for hydroxylation reactions
- Converts dopamine into norepi
Hydroxylation reactions are important in synthesizing… (2)
Collagen
Serotonin
Sources of Vitamin C
Fresh fruits and vegetables
4 classic symptoms of Vitamin C defiency (aka scurvy)?
2 Early symptoms
- Hemorrhage (bleeding gums, bruising)
- Hyperkeratosis of hair (kinky hair)
- Hematologic changes (anemia)
- Hypochondriasis (depression, weakness)
Early sx: weakness, achy joints
Name 2 potential benefits of Vitamin C megadoses
How does the body handle excess Vitamin C?
Shortened length of common cold
Improved wound healing
Vitamin C is easily excreted by kidneys
