Chapter 5: Vitamins Flashcards Preview

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Flashcards in Chapter 5: Vitamins Deck (23)
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1

Micronutrients

nutrients that are needed in very small amounts

2

Vitamins

organic compounds made of carbon, hydrogen, oxygen, and sometimes, nitrogen or other elements

3

Oxidation

a chemical reaction in which a substance combines with oxygen; the loss of electrons in an atom

4

Provitamins

precursors of vitamins

5

Enzymes

proteins produced by cells that catalyze chemical reactions within the body without undergoing change themselves

6

Coenzymes

organic molecules that activate an enzyme

7

Free Radicals

highly unstable, highly reactive molecular fragments with one or more unpaired electrons

8

Antioxidants

substances that donate electrons to free radicals to prevent oxidation

9

Food Additives

substances added intentionally or unintentionally to food that affect its character

10

Enrich

to add nutrients back that were lost during processing; for example, white flour is enriched with B vitamins lost when the bran and germ layers are removed

11

Fortified

to add nutrients to a food that were either not originally present or were present in insignificant amounts

12

Megadoses

amounts at least 10 times greater than the Recommended Dietary Allowance (RDA)

13

Preformed Vitamin A

the active form of vitamin A

14

Carotenoids

a group name of retinol precursors found in plants

15

Essential Nutrient

a nutrient that must be supplied by the
diet because it is not synthesized in the body. Essentiality does not refer to importance, merely to the need for a dietary source

16

IU: International Units

the former unit of measure of vitamin D that has been replaced by micrograms of cholecalciferol, the active form of vitamin D. To convert micrograms of vitamin D to IU, mul- tiply micrograms by 40

17

Rickets

vitamin D deficiency disease in children, most prominently characterized by bowed legs

18

Osteomalacia

adult rickets characterized by inadequate bone mineralization due to the lack of vitamin D

19

Homocysteine

an amino acid correlated with increased risk of heart disease

20

Methionine

an essential amino acid

21

Niacin Equivalents (NEs)

the amount of niacin available to the body including that made from tryptophan

22

Dietary Folate Equivalents (DFEs)

DFE = microgram of food folate + (1.7 x micrograms synthetic folic acid)

23

Phytochemicals

bioactive, nonnutrient plant compounds associated with a reduced risk of chronic diseases