Chapter 9
Identify vitamins that are fat soluble and water soluble.
ADEK
Identify individuals at risk for vitamin B12 deficiency and discuss why.
Aging people: decreased hydrochloric acid production Stomach missing parts: Roux-en-Y surgery or stomach cancer - intrinsic factor not produced by the stomach Others: vegans and some vegetarians - vitamin B12 occurs in animal products
List the functions of niacin, vitamin B12
B12: essential in converting folate into forms that the cell can use Niacin: used to release energy from macronutrients, synthesis of fatty acids
Vitamin K
Blood clotting
Identify the common function of all B vitamins.
Coenzymes or cofactors in energy metabolism
Intrinsic factor
Required for B12 absorption, reduced in bypass surgeries
Identify individuals who have an increased requirement for vitamin C.
SMOKERS
Homocysteine
amino acid that is found in our cells and blood. Elevated levels linked to increased risk for heart disease
Pernicious anemia
due to lack of intrinsic factor,
List the B vitamins associated with lowering homocysteine levels in the blood.
Folate, B12, B6
Describe the deficiency and toxicity conditions associated with vitamin A.
Deficiency: early stages - reversible night blindness Short term: cornea becomes dry and damaged Long term: Xerophthalmia (irreversible) Toxicity: liver damage and birth defects
Outline the synthesis and activation of vitamin D in the body.
Diet or liver cholesterol combine with UV rays, precursors form of vitamin D, makes its way to the liver then kidneys where it becomes active form of vitamin D
Vitamin E
Fat-soluble antioxidant Neutralizes ree radicals that can damage cell membranes, DNA, and proteins Enhances the immune system Nerve cell development
State the recommendation of vitamin B12 for those over the age of 50.
Increase intake from fortified foods
Pellagra
Niacin deficiency 4Ds
List unique sources of the B vitamins niacin, vitamin B12, folate, folic acid, biotin.
Niacin: synthesized from tryptophan B12: synthesized by bacteria and other microorganisms - naturally occurring in only animal foods (inside of the protein) Folate: orange juice, leafy greens, legumes Folic acid: supplements and enriched grains Biotin: gut bacteria
Beriberi
Thiamin deficiency not related to alcoholism
Discuss the deficiency conditions associated with the individual B-vitamins discussed in class.
Thiamin: Beriberi (not alcohol related) and Wernicke-Korsakoff syndrome (related to alcoholism) Riboflavin: sore throat, cracks in the corner of the mouth, glossy tongue, skin rashes, and hypersensitivity to light Niacin: Pellagra - 4 Ds B6: anemia - depression, vomiting, dermatitis, convulsions, anemia, and decreased immune response Folate/Folic acid: Macrocytic anemia, Neural tube defects (spina bifidia, anencephaly) B12: Macrocytic anemia or Pernicious anemia (due to lack of intrinsic factor) Biotin: Rarely occurs (neurological impairment, hair loss, and skin rashes Pantothenic acid: rare (fatigue, neurological disturbances, and gastrointestinal distress