Nutrition

Question 1

Vitamin A

Answer 1

SCIENTFIC NAME: Retinoids

ACTIVE FORMS: Retinaldehyde/ retinoic acid
FUNCTIONS: (1) vision (particularly dim light) (2) critical in limb development
(3) aids in immune response

DEFICIENCY SYMPTOMS/DISEASES: (1) night blindness (early sign) (2)dedifferentiation of epithelial cells and epithelial keratinization (3) Xerophthalmia cardinal signs of deficiency (early conjunctival xerosis, bitot’s spots, keratomalacia)

TOXICITY SYMPTOMS: acute: nausea, gingiva (redness), vomiting/headache and peeling of skin. chronic: weight-loss, fever, bone tenderness, rash

Question 2

Vitamin D

Answer 2

SCIENTFIC NAME: Cholecalciferol

SYNTHESIS: In dermis and epidermis from cholesterol

ACTIVE FORMS vs CIRCULATING: active: 1,25-(OH)2-D3; circulating 25-OH-D3

FUNCTIONS: maintain serum calcium and phosphorus [ ]

DEFICIENCY SYMPTOMS/DISEASES: rickets in kids; osteomalacia in adults. bowing of legs/arms. Elderly people and people of color are most at risk.

Question 3

Vitamin E

Answer 3

SCIENTFIC NAME: Tocopherols

FUNCTION: Antioxidant, vasodilator, decreases clotting

Question 4

Vitamin K

Answer 4

SCIENTFIC NAME: Phylloquinone

FUNCTIONS: Essential component of coagulation cascade. Co-factor for carboxylation and protein function

DEFICIENCY SYMPTOMS/DISEASES/TREATMENT: Cardinal sign: bleeding, poor coagulation. Deficiency in newborns is significant and can cause immature liver. Vitamin K prophylaxis given at birth in most developed countries.

Question 5

Vitamin B1

Answer 5

SCIENCTIFIC NAME: Thiamin

FUNCTION: Coenzyme for metabolism. Important rule in pyruvate dehydrogenase function.

DEFICIENCY SYMPTOMS/DISEASE: Caused by inadequate intake or sever alcoholism. Can cause dry beriberi (neuromuscular issues), wet beriberi (cardiac issues + dry beriberi), cerebral beriberi (Wernicke’s encephalothopy) or infantile beriberi (cardiac/neural issues).

Question 6

Vitamin B2

Answer 6

SCIENTIFIC NAME: Riboflavin

DEFICIENCY SYMTPOMS: angular stomatitis, fluorescent yellow urine, non-specific signs and symptoms.

Question 7

Niacin

Answer 7

FUNCTION: Coenzyme for redox reactions. Needed for PDH function.

DEFICIENCY SYMPTOMS/DISEASE: Pellegra. The 4 D’s (diarrhea, dermatosis [cassal’s necklace], dementia, and death)

Question 8

Folate/B12

Answer 8

B12 is also known as Cobalamin.

FUNCTIONS: folate - coenzymes for purine/pyrimidine synthesis. B12- coenzyme for methionine synthase and methylmalonyl-CoA mutase. Together synthesize thymidylate.

THF is the major source for folate. B12 is needed for THF usage, or else folate is trapped in methylated form (Methyl Trap).

DEFICIENCY SYMPTOMS/DISEASES: folic- megaloblastic anemia, ineffective hematopoiesis. B12- Pernicious anemia due to lack of intrinsic factor

Meat is the best source so vegans are at risk of deficiency.

You will see an increase in mevamalonyl acid.

B12 ABSORPTION: Absorbed in complex with IF in the distal ileum via receptor-mediated transport.

Question 9

Vitamin C

Answer 9

SCIENTIFIC NAME: Ascorbic acid

FUNCTIONS: Crosslinking of collagen; also used for reactions requiring reduced metal ion (iron or copper)

DEFCIENCY SYMPTOMS/DISEASE: scurvy (connective tissue defects, bleeding, gingiva)

Question 10

Calcium

Answer 10

FUNCTION: skeletal structure, messenger, stabilizes activity of many proteases and blood clotting enzymes

HOMESTATIC REGULATION: plasma calcium tightly regulated at 2.5 mM. Absorption is enhanced by vitamin D

Question 11

Iodine

Answer 11

FUNCTIONS: Component of thyroid hormones

DEFICIENCY SYMPTOMS: endemic goiter and endemic cretinism (stunted physical and and mental growth)

TOXICITY SYMPTOMS: Also may result in goiter.