Vitamin C (Ascorbic Acid)

Question 1

V-C enzyme

Answer 1

Gulonolactone oxidase (makes V-C)

Question 2

V-C food sources

Answer 2

• citrus
• cabbage
• dark green veggies
• cantaloupe
• strawberries
• lettuce
• tomatoes
• potatoes
• papaya
• mango

Question 3

V-C RDA

Answer 3

• 75 mg females
• 90 mg males
• 35 mg smokers- free radicals help V-C to the body

UL=2000 mg

Question 4

V-C absorption

Answer 4

• rate decreases with increase intake
• high intake=6 g=16%
• low intake= <20 mg= 98%
• oxidized to DHAA before absorption
• active transport

Question 5

V-C functions

Answer 5

1. antioxidant:
   - -reducing agent
   - -donates electrons
   - -reacts with free radicals
2. collagen synthesis:
   - -major component of connective tissue
   - -strengthens blood vessel walls/forms scar tissue
   - -bone growth
3. tyrosine synthesis/metabolism
   - -nor epinephrine
   - -dopamine
4. other
   - -serotonin synthesis from tryptopham
   - -caritine from trimethylsine

Question 6

V-C diseases

Answer 6

• common cold- 1 g/d= decrease in duration and severity not in the number of colds
• acts as antihistamine
• cancer- esophageal/stomach cancer

Question 7

V-C deficiency

Answer 7

• poor wound healing
• reduce resistance to infections
• swollen, bleeding gums
• bone/joint pain
• anemia/scurvy
• -<10 mg/d
• -skin decoloration, bruising, wound healing

Question 8

V-C toxicity

Answer 8

• > 2g (2000 mg)- GI problems
• kidney stones-avoid >500 mg
• hemochromatosis

Question 9

V-C nutrition assessment

Answer 9

• plasma or serum level

- WBC